Add generic reader

2025-09-27 12:52:20 +08:00 · 2020-09-06 23:01:33 -07:00
113 changed files with 2441 additions and 4007 deletions
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -18,7 +18,7 @@ jobs:
      - name: Checkout
        uses: actions/checkout@v2
      - name: Setup Go
-        uses: actions/setup-go@v2
+        uses: actions/setup-go@v1
        with:
          go-version: ${{ matrix.go }}
      - name: Install dependencies
@@ -30,17 +30,15 @@ jobs:
            libvpx-dev \
            libx264-dev
      - name: go vet
-        run: go vet $(go list ./... | grep -v mmal)
+        run: go vet ./...
      - name: go build
-        run: go build $(go list ./... | grep -v mmal)
+        run: go build ./...
      - name: go build without CGO
        run: go build . pkg/...
        env:
          CGO_ENABLED: 0
      - name: go test
-        run: go test -v -race -coverprofile=coverage.txt -covermode=atomic $(go list ./... | grep -v mmal)
-      - uses: codecov/codecov-action@v1
-        if: matrix.go == '1.15'
+        run: go test ./... -v -race
      - name: go test without CGO
        run: go test . pkg/... -v
        env:
@@ -55,7 +53,7 @@ jobs:
      - name: Checkout
        uses: actions/checkout@v2
      - name: Setup Go
-        uses: actions/setup-go@v2
+        uses: actions/setup-go@v1
        with:
          go-version: ${{ matrix.go }}
      - name: Install dependencies
@@ -66,15 +64,15 @@ jobs:
            libvpx \
            x264
      - name: go vet
-        run: go vet $(go list ./... | grep -v mmal)
+        run: go vet ./...
      - name: go build
-        run: go build $(go list ./... | grep -v mmal)
+        run: go build ./...
      - name: go build without CGO
        run: go build . pkg/...
        env:
          CGO_ENABLED: 0
      - name: go test
-        run: go test -v -race $(go list ./... | grep -v mmal)
+        run: go test ./... -v -race
      - name: go test without CGO
        run: go test . pkg/... -v
        env:
--- a/1
+++ b/1
@@ -0,0 +1 @@
+* @lherman-cs @at-wat
--- a/README.md
+++ b/README.md
@@ -1,237 +1,75 @@
-<h1 align="center">
-  <br>
-  Pion MediaDevices
-  <br>
-</h1>
-<h4 align="center">Go implementation of the <a href="https://developer.mozilla.org/en-US/docs/Web/API/MediaDevices">MediaDevices</a> API</h4>
-<p align="center">
-  <a href="https://pion.ly/slack"><img src="https://img.shields.io/badge/join-us%20on%20slack-gray.svg?longCache=true&logo=slack&colorB=brightgreen" alt="Slack Widget"></a>
-  <a href="https://github.com/pion/mediadevices/actions"><img src="https://github.com/pion/mediadevices/workflows/CI/badge.svg?branch=master" alt="Build status"></a> 
-  <a href="https://pkg.go.dev/github.com/pion/mediadevices"><img src="https://godoc.org/github.com/pion/mediadevices?status.svg" alt="GoDoc"></a>
-  <a href="https://codecov.io/gh/pion/mediadevices"><img src="https://codecov.io/gh/pion/mediadevices/branch/master/graph/badge.svg" alt="Coverage Status"></a>
-  <a href="LICENSE"><img src="https://img.shields.io/badge/License-MIT-yellow.svg" alt="License: MIT"></a>
-</p>
-<br>
+# mediadevices

-`mediadevices` provides access to media input devices like cameras, microphones, and screen capture. It can also be used to encode your video/audio stream to various codec selections. `mediadevices` abstracts away the complexities of interacting with things like hardware and codecs allowing you to focus on building appilcations, interacting only with an amazingly simple, easy, and elegant API!
+Go implementation of the [MediaDevices](https://developer.mozilla.org/en-US/docs/Web/API/MediaDevices) API.

-## Install
+![](img/demo.gif)

-`go get -u github.com/pion/mediadevices`
+## Interfaces
+
+| Interface  | Linux | Mac | Windows |
+| :--------: | :---: | :-: | :-----: |
+|   Camera   |  ✔️   | ✔️  |   ✔️    |
+| Microphone |  ✔️   | ✖️  |   ✔️    |
+|   Screen   |  ✔️   | ✖️  |   ✖️    |
+
+### Camera
+
+|   OS    |                           Library/Interface                             |
+| :-----: | :---------------------------------------------------------------------: |
+|  Linux  |        [Video4Linux](https://en.wikipedia.org/wiki/Video4Linux)         |
+|   Mac   |       [AVFoundation](https://developer.apple.com/av-foundation/)        |
+| Windows | [DirectShow](https://docs.microsoft.com/en-us/windows/win32/directshow) |
+
+|                     Pixel Format                      | Linux | Mac | Windows |
+| :---------------------------------------------------: | :---: | :-: | :-----: |
+| [YUY2](https://www.fourcc.org/pixel-format/yuv-yuy2/) |  ✔️   | ✖️  |   ✔️    |
+| [UYVY](https://www.fourcc.org/pixel-format/yuv-uyvy/) |  ✔️   | ✔️  |   ✖️    |
+| [I420](https://www.fourcc.org/pixel-format/yuv-i420/) |  ✔️   | ✖️  |   ✖️    |
+| [NV21](https://www.fourcc.org/pixel-format/yuv-nv21/) |  ✔️   | ✔️  |   ✖️    |
+|         [MJPEG](https://www.fourcc.org/mjpg/)         |  ✔️   | ✖️  |   ✖️    |
+
+### Microphone
+
+|   OS    |                            Library/Interface                            |
+| :-----: | :---------------------------------------------------------------------: |
+|  Linux  |         [PulseAudio](https://en.wikipedia.org/wiki/PulseAudio)          |
+|   Mac   |                                   N/A                                   |
+| Windows |  [waveIn](https://docs.microsoft.com/en-us/windows/win32/api/mmeapi/)   |
+
+### Screen casting
+
+|   OS    |                            Library/Interface                            |
+| :-----: | :---------------------------------------------------------------------: |
+|  Linux  |          [X11](https://en.wikipedia.org/wiki/X_Window_System)           |
+|   Mac   |                                   N/A                                   |
+| Windows |                                   N/A                                   |
+
+## Codecs
+
+| Audio Codec |                    Library/Interface                     |
+| :---------: | :------------------------------------------------------: |
+|    OPUS     | [libopus](http://opus-codec.org/)                        |
+
+| Video Codec |                    Library/Interface                     |
+| :---------: | :------------------------------------------------------: |
+|    H.264    | [OpenH264](https://www.openh264.org/)                    |
+|     VP8     | [libvpx](https://www.webmproject.org/code/)              |
+|     VP9     | [libvpx](https://www.webmproject.org/code/)              |

 ## Usage

-The following snippet shows how to capture a camera stream and store a frame as a jpeg image:
-
-```go
-package main
-
-import (
-	"image/jpeg"
-	"os"
-
-	"github.com/pion/mediadevices"
-	"github.com/pion/mediadevices/pkg/prop"
-
-	// This is required to register camera adapter
-	_ "github.com/pion/mediadevices/pkg/driver/camera" 
-	// Note: If you don't have a camera or your adapters are not supported,
-	//       you can always swap your adapters with our dummy adapters below.
-	// _ "github.com/pion/mediadevices/pkg/driver/videotest"
-)
-
-func main() {
-	stream, _ := mediadevices.GetUserMedia(mediadevices.MediaStreamConstraints{
-		Video: func(constraint *mediadevices.MediaTrackConstraints) {
-			// Query for ideal resolutions
-			constraint.Width = prop.Int(600)
-			constraint.Height = prop.Int(400)
-		},
-	})
-
-	// Since track can represent audio as well, we need to cast it to 
-	// *mediadevices.VideoTrack to get video specific functionalities
-	track := stream.GetVideoTracks()[0]
-	videoTrack := track.(*mediadevices.VideoTrack)
-	defer videoTrack.Close()
-
-	// Create a new video reader to get the decoded frames. Release is used 
-	// to return the buffer to hold frame back to the source so that the buffer 
-	// can be reused for the next frames.
-	videoReader := videoTrack.NewReader(false)
-	frame, release, _ := videoReader.Read()
-	defer release()
-
-	// Since frame is the standard image.Image, it's compatible with Go standard 
-	// library. For example, capturing the first frame and store it as a jpeg image.
-	output, _ := os.Create("frame.jpg")
-	jpeg.Encode(output, frame, nil)
-}
-
-
-```
-
-## More Examples
-
-* [Webrtc](/examples/webrtc) - Use Webrtc to create a realtime peer-to-peer video call
-* [Face Detection](/examples/facedetection) - Use a machine learning algorithm to detect faces in a camera stream
-* [RTP Stream](examples/rtp) - Capture camera stream, encode it in H264/VP8/VP9, and send it to a RTP server
-* [HTTP Broadcast](/examples/http) - Broadcast camera stream through HTTP with MJPEG
-* [Archive](/examples/archive) - Archive H264 encoded video stream from a camera
-
-## Available Media Inputs
-
-| Input  | Linux | Mac | Windows |
-| :--------: | :---: | :-: | :-----: |
-|   Camera   |  ✔️   | ✔️  |   ✔️    |
-| Microphone |  ✔️   | ✔️  |   ✔️    |
-|   Screen   |  ✔️   | ✔️  |   ✔️    |
-
-By default, there's no media input registered. This decision was made to allow you to pay what you need. Therefore, you need to import the associated packages for the media inputs. For example, if you want to use a camera, you need to import the camera package as a side effect:
-
-```go
-import (
-	...
-	_ "github.com/pion/mediadevices/pkg/driver/camera"
-)
-```
-
-## Available Codecs
-
-In order to encode your video/audio, `mediadevices` needs to know what codecs that you want to use and their parameters. To do this, you need to import the associated packages for the codecs, and add them to the codec selector that you'll pass to `GetUserMedia`:
-
-```go
-package main
-
-import (
-	"github.com/pion/mediadevices"
-	"github.com/pion/mediadevices/pkg/codec/x264"      // This is required to use H264 video encoder
-	_ "github.com/pion/mediadevices/pkg/driver/camera" // This is required to register camera adapter
-)
-
-func main() {
-	// configure codec specific parameters
-	x264Params, _ := x264.NewParams()
-	x264Params.Preset = x264.PresetMedium
-	x264Params.BitRate = 1_000_000 // 1mbps
-
-	codecSelector := mediadevices.NewCodecSelector(
-		mediadevices.WithVideoEncoders(&x264Params),
-	)
-	
-	mediaStream, _ := mediadevices.GetUserMedia(mediadevices.MediaStreamConstraints{
-		Video: func(c *mediadevices.MediaTrackConstraints) {},
-		Codec: codecSelector, // let GetUsermedia know available codecs
-	})
-}
-```
-
-Since `mediadevices` doesn't implement the video/audio codecs, it needs to call the codec libraries from the system through cgo. Therefore, you're required to install the codec libraries before you can use them in `mediadevices`. In the next section, it shows a list of available codecs, where the packages are defined (documentation linked), and installation instructions.
-
-Note: we do not provide recommendations on choosing one codec or another as it is very complex and can be subjective.
-
-### Video Codecs
-
-#### x264
-A free software library and application for encoding video streams into the H.264/MPEG-4 AVC compression format.
-
-* Package: [github.com/pion/mediadevices/pkg/codec/x264](https://pkg.go.dev/github.com/pion/mediadevices/pkg/codec/x264)
-* Installation:
-  * Mac: `brew install x264`
-  * Ubuntu: `apt install libx264-dev`
-  
-#### mmal
-A framework to enable H264 hardware encoding for Raspberry Pi or boards that use VideoCore GPUs.
-
-* Package: [github.com/pion/mediadevices/pkg/codec/mmal](https://pkg.go.dev/github.com/pion/mediadevices/pkg/codec/mmal)
-* Installation: no installation needed, mmal should come built in Raspberry Pi devices
-
-#### openh264
-A codec library which supports H.264 encoding and decoding. It is suitable for use in real time applications.
-
-* Package: [github.com/pion/mediadevices/pkg/codec/openh264](https://pkg.go.dev/github.com/pion/mediadevices/pkg/codec/openh264)
-* Installation: no installation needed, included as a static binary
-
-#### vpx
-A free software video codec library from Google and the Alliance for Open Media that implements VP8/VP9 video coding formats.
-
-* Package: [github.com/pion/mediadevices/pkg/codec/vpx](https://pkg.go.dev/github.com/pion/mediadevices/pkg/codec/vpx)
-* Installation:
-  * Mac: `brew install libvpx`
-  * Ubuntu: `apt install libvpx-dev`
-  
-#### vaapi
-An open source API that allows applications such as VLC media player or GStreamer to use hardware video acceleration capabilities (currently support VP8/VP9).
-
-* Package: [github.com/pion/mediadevices/pkg/codec/vaapi](https://pkg.go.dev/github.com/pion/mediadevices/pkg/codec/vaapi)
-* Installation:
-  * Ubuntu: `apt install libva-dev`
-
-
-### Audio Codecs
-
-#### opus
-A totally open, royalty-free, highly versatile audio codec.
-
-* Package: [github.com/pion/mediadevices/pkg/codec/opus](https://pkg.go.dev/github.com/pion/mediadevices/pkg/codec/opus)
-* Installation:
-  * Mac: `brew install opus`
-  * Ubuntu: `apt install libopus-dev`
-
-## Benchmark
-
-Result as of Nov 4, 2020 with Go 1.14 on a Raspberry pi 3, `mediadevices` can produce video, encode, send across network, and decode at **720p, 30 fps with < 500 ms latency**.  
-
-The test was taken by capturing a camera stream, decoding the raw frames, encoding the video stream with mmal, and sending the stream through Webrtc.
-
-## FAQ
-
-### Failed to find the best driver that fits the constraints
-
-`mediadevices` provides an automated driver discovery through `GetUserMedia` and `GetDisplayMedia`. The driver discover algorithm works something like:
-
-1. Open all registered drivers
-2. Get all properties (property describes what a driver is capable of, e.g. resolution, frame rate, etc.) from opened drivers
-3. Find the best property that meets the criteria
-
-So, when `mediadevices` returns `failed to find the best driver that fits the constraints` error, one of the following conditions might have occured:
-* Driver was not imported as a side effect in your program, e.g. `import _ github.com/pion/mediadevices/pkg/driver/camera`
-* Your constraint is too strict that there's no driver can fullfil your requirements. In this case, you can try to turn up the debug level by specifying the following environment variable: `export PION_LOG_DEBUG=all` to see what was too strict and tune that.
-* Your driver is not supported/implemented. In this case, you can either let us know (file an issue) and wait for the maintainers to implement it. Or, you can implement it yourself and register it through `RegisterDriverAdapter`
-
-### Failed to find vpx/x264/mmal/opus codecs
-
-Since `mediadevices` uses cgo to access video/audio codecs, it needs to find these libraries from the system. To accomplish this, [pkg-config](https://www.freedesktop.org/wiki/Software/pkg-config/) is used for library discovery.
-
-If you see the following error message at compile time:
-```
-# pkg-config --cflags  -- vpx
-Package vpx was not found in the pkg-config search path.
-Perhaps you should add the directory containing `vpx.pc'
-to the PKG_CONFIG_PATH environment variable
-No package 'vpx' found
-pkg-config: exit status 1
-```
-
-There are 2 common problems:
-
-* The required codec library is not installed (vpx in this example). In this case, please refer to the [available codecs](#available-codecs).
-* Pkg-config fails to find the `.pc` files for this codec ([reference](https://people.freedesktop.org/~dbn/pkg-config-guide.html#using)). In this case, you need to find where the codec library's `.pc` is stored, and let pkg-config knows with: `export PKG_CONFIG_PATH=/path/to/directory`.
-
-
-## Community
-Pion has an active community on the [Slack](https://pion.ly/slack).
-
-Follow the [Pion Twitter](https://twitter.com/_pion) for project updates and important WebRTC news.
-
-We are always looking to support **your projects**. Please reach out if you have something to build!
-If you need commercial support or don't want to use public methods you can contact us at [team@pion.ly](mailto:team@pion.ly)
+[Wiki](https://github.com/pion/mediadevices/wiki)

 ## Contributing
-Check out the **[contributing wiki](https://github.com/pion/webrtc/wiki/Contributing)** to join the group of amazing people making this project possible:

-* [Lukas Herman](https://github.com/lherman-cs) - _Original Author_
+- [Lukas Herman](https://github.com/lherman-cs) - _Original Author_
 * [Atsushi Watanabe](https://github.com/at-wat) - _VP8, Screencast, etc._

-## License
-MIT License - see [LICENSE](LICENSE) for full text
+## Project Status
+
+[![Stargazers over time](https://starchart.cc/pion/mediadevices.svg)](https://starchart.cc/pion/mediadevices)
+
+## References
+
+- https://developer.mozilla.org/en-US/docs/Web/Media/Formats/WebRTC_codecs
+- https://tools.ietf.org/html/rfc7742
--- a/codec.go
+++ b/codec.go
@@ -1,135 +0,0 @@
-package mediadevices
-
-import (
-	"errors"
-	"fmt"
-	"strings"
-
-	"github.com/pion/mediadevices/pkg/codec"
-	"github.com/pion/mediadevices/pkg/io/audio"
-	"github.com/pion/mediadevices/pkg/io/video"
-	"github.com/pion/mediadevices/pkg/prop"
-	"github.com/pion/webrtc/v2"
-)
-
-// CodecSelector is a container of video and audio encoder builders, which later will be used
-// for codec matching.
-type CodecSelector struct {
-	videoEncoders []codec.VideoEncoderBuilder
-	audioEncoders []codec.AudioEncoderBuilder
-}
-
-// CodecSelectorOption is a type for specifying CodecSelector options
-type CodecSelectorOption func(*CodecSelector)
-
-// WithVideoEncoders replace current video codecs with listed encoders
-func WithVideoEncoders(encoders ...codec.VideoEncoderBuilder) CodecSelectorOption {
-	return func(t *CodecSelector) {
-		t.videoEncoders = encoders
-	}
-}
-
-// WithVideoEncoders replace current audio codecs with listed encoders
-func WithAudioEncoders(encoders ...codec.AudioEncoderBuilder) CodecSelectorOption {
-	return func(t *CodecSelector) {
-		t.audioEncoders = encoders
-	}
-}
-
-// NewCodecSelector constructs CodecSelector with given variadic options
-func NewCodecSelector(opts ...CodecSelectorOption) *CodecSelector {
-	var track CodecSelector
-
-	for _, opt := range opts {
-		opt(&track)
-	}
-
-	return &track
-}
-
-// Populate lets the webrtc engine be aware of supported codecs that are contained in CodecSelector
-func (selector *CodecSelector) Populate(setting *webrtc.MediaEngine) {
-	for _, encoder := range selector.videoEncoders {
-		setting.RegisterCodec(encoder.RTPCodec().RTPCodec)
-	}
-
-	for _, encoder := range selector.audioEncoders {
-		setting.RegisterCodec(encoder.RTPCodec().RTPCodec)
-	}
-}
-
-func (selector *CodecSelector) selectVideoCodecByNames(reader video.Reader, inputProp prop.Media, codecNames ...string) (codec.ReadCloser, *codec.RTPCodec, error) {
-	var selectedEncoder codec.VideoEncoderBuilder
-	var encodedReader codec.ReadCloser
-	var errReasons []string
-	var err error
-
-outer:
-	for _, wantCodec := range codecNames {
-		for _, encoder := range selector.videoEncoders {
-			if encoder.RTPCodec().Name == wantCodec {
-				encodedReader, err = encoder.BuildVideoEncoder(reader, inputProp)
-				if err == nil {
-					selectedEncoder = encoder
-					break outer
-				}
-			}
-
-			errReasons = append(errReasons, fmt.Sprintf("%s: %s", encoder.RTPCodec().Name, err))
-		}
-	}
-
-	if selectedEncoder == nil {
-		return nil, nil, errors.New(strings.Join(errReasons, "\n\n"))
-	}
-
-	return encodedReader, selectedEncoder.RTPCodec(), nil
-}
-
-func (selector *CodecSelector) selectVideoCodec(reader video.Reader, inputProp prop.Media, codecs ...*webrtc.RTPCodec) (codec.ReadCloser, *codec.RTPCodec, error) {
-	var codecNames []string
-
-	for _, codec := range codecs {
-		codecNames = append(codecNames, codec.Name)
-	}
-
-	return selector.selectVideoCodecByNames(reader, inputProp, codecNames...)
-}
-
-func (selector *CodecSelector) selectAudioCodecByNames(reader audio.Reader, inputProp prop.Media, codecNames ...string) (codec.ReadCloser, *codec.RTPCodec, error) {
-	var selectedEncoder codec.AudioEncoderBuilder
-	var encodedReader codec.ReadCloser
-	var errReasons []string
-	var err error
-
-outer:
-	for _, wantCodec := range codecNames {
-		for _, encoder := range selector.audioEncoders {
-			if encoder.RTPCodec().Name == wantCodec {
-				encodedReader, err = encoder.BuildAudioEncoder(reader, inputProp)
-				if err == nil {
-					selectedEncoder = encoder
-					break outer
-				}
-			}
-
-			errReasons = append(errReasons, fmt.Sprintf("%s: %s", encoder.RTPCodec().Name, err))
-		}
-	}
-
-	if selectedEncoder == nil {
-		return nil, nil, errors.New(strings.Join(errReasons, "\n\n"))
-	}
-
-	return encodedReader, selectedEncoder.RTPCodec(), nil
-}
-
-func (selector *CodecSelector) selectAudioCodec(reader audio.Reader, inputProp prop.Media, codecs ...*webrtc.RTPCodec) (codec.ReadCloser, *codec.RTPCodec, error) {
-	var codecNames []string
-
-	for _, codec := range codecs {
-		codecNames = append(codecNames, codec.Name)
-	}
-
-	return selector.selectAudioCodecByNames(reader, inputProp, codecNames...)
-}
--- a/codecov.yml
+++ b/codecov.yml
@@ -1,10 +0,0 @@
-coverage:
-  status:
-    project:
-      default:
-        # Allow decreasing 2% of total coverage to avoid noise.
-        threshold: 2%
-    patch: off
-
-ignore:
-  - "examples/*"
--- a/examples/archive/README.md
+++ b/examples/archive/README.md
@@ -1,38 +0,0 @@
-## Instructions
-
-### Install required codecs
-
-In this example, we'll be using x264 as our video codec. Therefore, we need to make sure that these codecs are installed within our system. 
-
-Installation steps:
-
-* [x264](https://github.com/pion/mediadevices#x264)
-
-### Download archive examplee
-
-```
-git clone https://github.com/pion/mediadevices.git
-```
-
-### Run archive example
-
-Run `cd mediadevices/examples/archive && go build && ./archive recorded.h264`
-
-To stop recording, press `Ctrl+c` or send a SIGINT signal.
-
-### Playback recorded video
-
-Install GStreamer and run:
-```
-gst-launch-1.0 playbin uri=file://${PWD}/recorded.h264
-```
-
-Or run VLC media plyer:
-```
-vlc recorded.h264
-```
-
-A video should start playing in your GStreamer or VLC window.
-
-Congrats, you have used pion-MediaDevices! Now start building something cool
-
--- a/examples/archive/archive
+++ b/examples/archive/archive
--- a/examples/archive/main.go
+++ b/examples/archive/main.go
@@ -1,82 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"image"
-	"io"
-	"os"
-	"os/signal"
-	"syscall"
-
-	"github.com/pion/mediadevices"
-	"github.com/pion/mediadevices/pkg/codec/x264"      // This is required to use H264 video encoder
-	_ "github.com/pion/mediadevices/pkg/driver/camera" // This is required to register camera adapter
-	"github.com/pion/mediadevices/pkg/frame"
-	"github.com/pion/mediadevices/pkg/io/video"
-	"github.com/pion/mediadevices/pkg/prop"
-)
-
-func must(err error) {
-	if err != nil {
-		panic(err)
-	}
-}
-
-func main() {
-	if len(os.Args) != 2 {
-		fmt.Printf("usage: %s <path/to/file.h264>\n", os.Args[0])
-		return
-	}
-	dest := os.Args[1]
-
-	sigs := make(chan os.Signal, 1)
-	signal.Notify(sigs, syscall.SIGINT)
-
-	x264Params, err := x264.NewParams()
-	must(err)
-	x264Params.Preset = x264.PresetMedium
-	x264Params.BitRate = 1_000_000 // 1mbps
-
-	codecSelector := mediadevices.NewCodecSelector(
-		mediadevices.WithVideoEncoders(&x264Params),
-	)
-
-	mediaStream, err := mediadevices.GetUserMedia(mediadevices.MediaStreamConstraints{
-		Video: func(c *mediadevices.MediaTrackConstraints) {
-			c.FrameFormat = prop.FrameFormat(frame.FormatYUY2)
-			c.Width = prop.Int(640)
-			c.Height = prop.Int(480)
-		},
-		Codec: codecSelector,
-	})
-	must(err)
-
-	videoTrack := mediaStream.GetVideoTracks()[0].(*mediadevices.VideoTrack)
-	defer videoTrack.Close()
-
-	videoTrack.Transform(video.TransformFunc(func(r video.Reader) video.Reader {
-		return video.ReaderFunc(func() (img image.Image, release func(), err error) {
-			// we send io.EOF signal to the encoder reader to stop reading. Therefore, io.Copy
-			// will finish its execution and the program will finish
-			select {
-			case <-sigs:
-				return nil, func() {}, io.EOF
-			default:
-			}
-
-			return r.Read()
-		})
-	}))
-
-	reader, err := videoTrack.NewEncodedReader(x264Params.RTPCodec().Name)
-	must(err)
-	defer reader.Close()
-
-	out, err := os.Create(dest)
-	must(err)
-
-	fmt.Println("Recording... Press Ctrl+c to stop")
-	_, err = io.Copy(out, reader)
-	must(err)
-	fmt.Println("Your video has been recorded to", dest)
-}
--- a/examples/facedetection/README.md
+++ b/examples/facedetection/README.md
@@ -1,15 +1,29 @@
 ## Instructions

-### Download facedetection example
+### Download facedetection

 ```
-git clone https://github.com/pion/mediadevices.git
+go get github.com/pion/mediadevices/examples/facedetection
 ```

-### Compile and Run facedetection
+### Open example page

-Run `cd mediadevices/examples/facedetection && go build && ./facedetection`
+[jsfiddle.net](https://jsfiddle.net/gh/get/library/pure/pion/mediadevices/tree/master/examples/internal/jsfiddle/video) you should see two text-areas and a 'Start Session' button

-You should be able to see some loggings when it can see faces.
+### Run facedetection with your browsers SessionDescription as stdin

-Congrats, you have used pion-MediaDevices! Now start building something cool
+In the jsfiddle the top textarea is your browser, copy that and:
+
+#### Linux
+
+Run `echo $BROWSER_SDP | facedetection`
+
+### Input facedetection's SessionDescription into your browser
+
+Copy the text that `facedetection` just emitted and copy into second text area
+
+### Hit 'Start Session' in jsfiddle, enjoy your video!
+
+A video should start playing in your browser above the input boxes, and will continue playing until you close the application.
+
+Congrats, you have used pion-WebRTC! Now start building something cool
--- a/examples/facedetection/detector.go
+++ b/examples/facedetection/detector.go
@@ -0,0 +1,118 @@
+package main
+
+import (
+	"image"
+	"image/color"
+	"image/draw"
+	"io/ioutil"
+	"log"
+
+	"github.com/disintegration/imaging"
+	pigo "github.com/esimov/pigo/core"
+)
+
+var (
+	cascade    []byte
+	err        error
+	classifier *pigo.Pigo
+)
+
+func imgToGrayscale(img image.Image) []uint8 {
+	bounds := img.Bounds()
+	flatten := bounds.Dy() * bounds.Dx()
+	grayImg := make([]uint8, flatten)
+
+	i := 0
+	for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
+		for x := bounds.Min.X; x < bounds.Max.X; x++ {
+			pix := img.At(x, y)
+			grayPix := color.GrayModel.Convert(pix).(color.Gray)
+			grayImg[i] = grayPix.Y
+			i++
+		}
+	}
+	return grayImg
+}
+
+// clusterDetection runs Pigo face detector core methods
+// and returns a cluster with the detected faces coordinates.
+func clusterDetection(img image.Image) []pigo.Detection {
+	grayscale := imgToGrayscale(img)
+	bounds := img.Bounds()
+	cParams := pigo.CascadeParams{
+		MinSize:     100,
+		MaxSize:     600,
+		ShiftFactor: 0.15,
+		ScaleFactor: 1.1,
+		ImageParams: pigo.ImageParams{
+			Pixels: grayscale,
+			Rows:   bounds.Dy(),
+			Cols:   bounds.Dx(),
+			Dim:    bounds.Dx(),
+		},
+	}
+
+	if len(cascade) == 0 {
+		cascade, err = ioutil.ReadFile("facefinder")
+		if err != nil {
+			log.Fatalf("Error reading the cascade file: %s", err)
+		}
+		p := pigo.NewPigo()
+
+		// Unpack the binary file. This will return the number of cascade trees,
+		// the tree depth, the threshold and the prediction from tree's leaf nodes.
+		classifier, err = p.Unpack(cascade)
+		if err != nil {
+			log.Fatalf("Error unpacking the cascade file: %s", err)
+		}
+	}
+
+	// Run the classifier over the obtained leaf nodes and return the detection results.
+	// The result contains quadruplets representing the row, column, scale and detection score.
+	dets := classifier.RunCascade(cParams, 0.0)
+
+	// Calculate the intersection over union (IoU) of two clusters.
+	dets = classifier.ClusterDetections(dets, 0)
+
+	return dets
+}
+
+func drawCircle(img draw.Image, x0, y0, r int, c color.Color) {
+	x, y, dx, dy := r-1, 0, 1, 1
+	err := dx - (r * 2)
+
+	for x > y {
+		img.Set(x0+x, y0+y, c)
+		img.Set(x0+y, y0+x, c)
+		img.Set(x0-y, y0+x, c)
+		img.Set(x0-x, y0+y, c)
+		img.Set(x0-x, y0-y, c)
+		img.Set(x0-y, y0-x, c)
+		img.Set(x0+y, y0-x, c)
+		img.Set(x0+x, y0-y, c)
+
+		if err <= 0 {
+			y++
+			err += dy
+			dy += 2
+		}
+		if err > 0 {
+			x--
+			dx += 2
+			err += dx - (r * 2)
+		}
+	}
+}
+
+func markFaces(img image.Image) image.Image {
+	nrgba := imaging.Clone(img)
+	dets := clusterDetection(img)
+	for _, det := range dets {
+		if det.Q < 5.0 {
+			continue
+		}
+
+		drawCircle(nrgba, det.Col, det.Row, det.Scale/2, color.Black)
+	}
+	return nrgba
+}
--- a/examples/facedetection/main.go
+++ b/examples/facedetection/main.go
@@ -1,107 +1,119 @@
 package main

 import (
+	"fmt"
 	"image"
-	"io/ioutil"
-	"log"
-	"time"

-	pigo "github.com/esimov/pigo/core"
 	"github.com/pion/mediadevices"
+	"github.com/pion/mediadevices/examples/internal/signal"
+	"github.com/pion/mediadevices/pkg/codec"
+	"github.com/pion/mediadevices/pkg/codec/vpx"       // This is required to use VP8/VP9 video encoder
 	_ "github.com/pion/mediadevices/pkg/driver/camera" // This is required to register camera adapter
 	"github.com/pion/mediadevices/pkg/frame"
+	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
+	"github.com/pion/webrtc/v2"
 )

-const (
-	confidenceLevel = 5.0
-)
-
-var (
-	cascade    []byte
-	classifier *pigo.Pigo
-)
-
-func must(err error) {
-	if err != nil {
-		panic(err)
-	}
-}
-
-func detectFace(frame *image.YCbCr) bool {
-	bounds := frame.Bounds()
-	cascadeParams := pigo.CascadeParams{
-		MinSize:     100,
-		MaxSize:     600,
-		ShiftFactor: 0.15,
-		ScaleFactor: 1.1,
-		ImageParams: pigo.ImageParams{
-			Pixels: frame.Y, // Y in YCbCr should be enough to detect faces
-			Rows:   bounds.Dy(),
-			Cols:   bounds.Dx(),
-			Dim:    bounds.Dx(),
-		},
-	}
-
-	// Run the classifier over the obtained leaf nodes and return the detection results.
-	// The result contains quadruplets representing the row, column, scale and detection score.
-	dets := classifier.RunCascade(cascadeParams, 0.0)
-
-	// Calculate the intersection over union (IoU) of two clusters.
-	dets = classifier.ClusterDetections(dets, 0)
-
-	for _, det := range dets {
-		if det.Q >= confidenceLevel {
-			return true
+func markFacesTransformer(r video.Reader) video.Reader {
+	return video.ReaderFunc(func() (img image.Image, err error) {
+		img, err = r.Read()
+		if err != nil {
+			return
 		}
-	}

-	return false
+		img = markFaces(img)
+		return
+	})
 }

 func main() {
-	// prepare face detector
-	var err error
-	cascade, err = ioutil.ReadFile("facefinder")
-	if err != nil {
-		log.Fatalf("Error reading the cascade file: %s", err)
-	}
-	p := pigo.NewPigo()
-
-	// Unpack the binary file. This will return the number of cascade trees,
-	// the tree depth, the threshold and the prediction from tree's leaf nodes.
-	classifier, err = p.Unpack(cascade)
-	if err != nil {
-		log.Fatalf("Error unpacking the cascade file: %s", err)
+	config := webrtc.Configuration{
+		ICEServers: []webrtc.ICEServer{
+			{
+				URLs: []string{"stun:stun.l.google.com:19302"},
+			},
+		},
 	}

-	mediaStream, err := mediadevices.GetUserMedia(mediadevices.MediaStreamConstraints{
+	// Wait for the offer to be pasted
+	offer := webrtc.SessionDescription{}
+	signal.Decode(signal.MustReadStdin(), &offer)
+
+	// Create a new RTCPeerConnection
+	mediaEngine := webrtc.MediaEngine{}
+	if err := mediaEngine.PopulateFromSDP(offer); err != nil {
+		panic(err)
+	}
+	api := webrtc.NewAPI(webrtc.WithMediaEngine(mediaEngine))
+	peerConnection, err := api.NewPeerConnection(config)
+	if err != nil {
+		panic(err)
+	}
+
+	// Set the handler for ICE connection state
+	// This will notify you when the peer has connected/disconnected
+	peerConnection.OnICEConnectionStateChange(func(connectionState webrtc.ICEConnectionState) {
+		fmt.Printf("Connection State has changed %s \n", connectionState.String())
+	})
+
+	md := mediadevices.NewMediaDevices(peerConnection)
+
+	vp8Params, err := vpx.NewVP8Params()
+	if err != nil {
+		panic(err)
+	}
+	vp8Params.BitRate = 100000 // 100kbps
+
+	s, err := md.GetUserMedia(mediadevices.MediaStreamConstraints{
 		Video: func(c *mediadevices.MediaTrackConstraints) {
-			c.FrameFormat = prop.FrameFormatExact(frame.FormatUYVY)
+			c.FrameFormat = prop.FrameFormatExact(frame.FormatI420) // most of the encoder accepts I420
+			c.Enabled = true
 			c.Width = prop.Int(640)
 			c.Height = prop.Int(480)
+			c.VideoTransform = markFacesTransformer
+			c.VideoEncoderBuilders = []codec.VideoEncoderBuilder{&vp8Params}
 		},
 	})
-	must(err)
-
-	// since we're trying to access the raw data, we need to cast Track to its real type, *mediadevices.VideoTrack
-	videoTrack := mediaStream.GetVideoTracks()[0].(*mediadevices.VideoTrack)
-	defer videoTrack.Close()
-
-	videoReader := videoTrack.NewReader(false)
-	// To save resources, we can simply use 4 fps to detect faces.
-	ticker := time.NewTicker(time.Millisecond * 250)
-	defer ticker.Stop()
-
-	for range ticker.C {
-		frame, release, err := videoReader.Read()
-		must(err)
-
-		// Since we asked the frame format to be exactly YUY2 in GetUserMedia, we can guarantee that it must be YCbCr
-		if detectFace(frame.(*image.YCbCr)) {
-			log.Println("Detect a face")
-		}
-
-		release()
+	if err != nil {
+		panic(err)
 	}
+
+	for _, tracker := range s.GetTracks() {
+		t := tracker.Track()
+		tracker.OnEnded(func(err error) {
+			fmt.Printf("Track (ID: %s, Label: %s) ended with error: %v\n",
+				t.ID(), t.Label(), err)
+		})
+		_, err = peerConnection.AddTransceiverFromTrack(t,
+			webrtc.RtpTransceiverInit{
+				Direction: webrtc.RTPTransceiverDirectionSendonly,
+			},
+		)
+		if err != nil {
+			panic(err)
+		}
+	}
+
+	// Set the remote SessionDescription
+	err = peerConnection.SetRemoteDescription(offer)
+	if err != nil {
+		panic(err)
+	}
+
+	// Create an answer
+	answer, err := peerConnection.CreateAnswer(nil)
+	if err != nil {
+		panic(err)
+	}
+
+	// Sets the LocalDescription, and starts our UDP listeners
+	err = peerConnection.SetLocalDescription(answer)
+	if err != nil {
+		panic(err)
+	}
+
+	// Output the answer in base64 so we can paste it in browser
+	fmt.Println(signal.Encode(answer))
+	select {}
 }
--- a/examples/go.mod
+++ b/examples/go.mod
@@ -2,8 +2,8 @@ module github.com/pion/mediadevices/examples

 go 1.14

+replace github.com/pion/mediadevices => ../
+
 // Please don't commit require entries of examples.
 // `git checkout master examples/go.mod` to revert this file.
-require github.com/pion/mediadevices v0.0.0
-
-replace github.com/pion/mediadevices v0.0.0 => ../
+require github.com/pion/mediadevices v0.0.0-00010101000000-000000000000
--- a/examples/http/README.md
+++ b/examples/http/README.md
@@ -1,19 +0,0 @@
-## Instructions
-
-### Download http example
-
-```
-git clone https://github.com/pion/mediadevices.git
-```
-
-### Compile and Run HTTP server
-
-Run `cd mediadevices/examples/http && go build && ./http :1313`
-
-
-### Access the camera stream from the browser
-
-Go to "http://localhost:1313"
-
-
-Congrats, you have used pion-MediaDevices! Now start building something cool
--- a/examples/http/main.go
+++ b/examples/http/main.go
@@ -1,85 +0,0 @@
-// This is an example of using mediadevices to broadcast your camera through http.
-// The example doesn't aim to be performant, but rather it strives to be simple.
-package main
-
-import (
-	"bytes"
-	"fmt"
-	"image/jpeg"
-	"io"
-	"log"
-	"mime/multipart"
-	"net/http"
-	"net/textproto"
-	"os"
-
-	"github.com/pion/mediadevices"
-	"github.com/pion/mediadevices/pkg/prop"
-
-	// Note: If you don't have a camera or microphone or your adapters are not supported,
-	//       you can always swap your adapters with our dummy adapters below.
-	// _ "github.com/pion/mediadevices/pkg/driver/videotest"
-	_ "github.com/pion/mediadevices/pkg/driver/camera" // This is required to register camera adapter
-)
-
-func must(err error) {
-	if err != nil {
-		panic(err)
-	}
-}
-
-func main() {
-	if len(os.Args) != 2 {
-		fmt.Printf("usage: %s host:port\n", os.Args[0])
-		return
-	}
-	dest := os.Args[1]
-
-	mediaStream, err := mediadevices.GetUserMedia(mediadevices.MediaStreamConstraints{
-		Video: func(constraint *mediadevices.MediaTrackConstraints) {
-			constraint.Width = prop.Int(600)
-			constraint.Height = prop.Int(400)
-		},
-	})
-	must(err)
-
-	track := mediaStream.GetVideoTracks()[0]
-	videoTrack := track.(*mediadevices.VideoTrack)
-	defer videoTrack.Close()
-
-	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
-		var buf bytes.Buffer
-		videoReader := videoTrack.NewReader(false)
-		mimeWriter := multipart.NewWriter(w)
-
-		contentType := fmt.Sprintf("multipart/x-mixed-replace;boundary=%s", mimeWriter.Boundary())
-		w.Header().Add("Content-Type", contentType)
-
-		partHeader := make(textproto.MIMEHeader)
-		partHeader.Add("Content-Type", "image/jpeg")
-
-		for {
-			frame, release, err := videoReader.Read()
-			if err == io.EOF {
-				return
-			}
-			must(err)
-
-			err = jpeg.Encode(&buf, frame, nil)
-			// Since we're done with img, we need to release img so that that the original owner can reuse
-			// this memory.
-			release()
-			must(err)
-
-			partWriter, err := mimeWriter.CreatePart(partHeader)
-			must(err)
-
-			_, err = partWriter.Write(buf.Bytes())
-			buf.Reset()
-			must(err)
-		}
-	})
-
-	fmt.Printf("listening on %s\n", dest)
-	log.Println(http.ListenAndServe(dest, nil))
-}
--- a/examples/rtp-send/README.md
+++ b/examples/rtp-send/README.md
@@ -0,0 +1,29 @@
+## Instructions
+
+### Download rtp-send example
+
+```
+go get github.com/pion/mediadevices/examples/rtp-send
+```
+
+### Listen RTP
+
+Install GStreamer and run:
+```
+gst-launch-1.0 udpsrc port=5000 caps=application/x-rtp,encode-name=VP8 \
+    ! rtpvp8depay ! vp8dec ! videoconvert ! autovideosink
+```
+
+Or run VLC media plyer:
+```
+vlc ./vp8.sdp
+```
+
+### Run rtp-send
+
+Run `rtp-send localhost:5000`
+
+A video should start playing in your GStreamer or VLC window.
+It's not WebRTC, but pure RTP.
+
+Congrats, you have used pion-MediaDevices! Now start building something cool
--- a/examples/rtp-send/main.go
+++ b/examples/rtp-send/main.go
@@ -0,0 +1,120 @@
+package main
+
+import (
+	"fmt"
+	"net"
+	"os"
+
+	"github.com/pion/mediadevices"
+	"github.com/pion/mediadevices/pkg/codec"
+	"github.com/pion/mediadevices/pkg/codec/vpx"       // This is required to use VP8/VP9 video encoder
+	_ "github.com/pion/mediadevices/pkg/driver/camera" // This is required to register camera adapter
+	"github.com/pion/mediadevices/pkg/frame"
+	"github.com/pion/mediadevices/pkg/prop"
+	"github.com/pion/rtp"
+	"github.com/pion/webrtc/v2"
+	"github.com/pion/webrtc/v2/pkg/media"
+)
+
+const (
+	mtu = 1000
+)
+
+func main() {
+	if len(os.Args) != 2 {
+		fmt.Printf("usage: %s host:port\n", os.Args[0])
+		return
+	}
+
+	md := mediadevices.NewMediaDevicesFromCodecs(
+		map[webrtc.RTPCodecType][]*webrtc.RTPCodec{
+			webrtc.RTPCodecTypeVideo: []*webrtc.RTPCodec{
+				webrtc.NewRTPVP8Codec(100, 90000),
+			},
+		},
+		mediadevices.WithTrackGenerator(
+			func(_ uint8, _ uint32, id, _ string, codec *webrtc.RTPCodec) (
+				mediadevices.LocalTrack, error,
+			) {
+				return newTrack(codec, id, os.Args[1]), nil
+			},
+		),
+	)
+
+	vp8Params, err := vpx.NewVP8Params()
+	if err != nil {
+		panic(err)
+	}
+	vp8Params.BitRate = 100000 // 100kbps
+
+	_, err = md.GetUserMedia(mediadevices.MediaStreamConstraints{
+		Video: func(c *mediadevices.MediaTrackConstraints) {
+			c.FrameFormat = prop.FrameFormat(frame.FormatYUY2)
+			c.Enabled = true
+			c.Width = prop.Int(640)
+			c.Height = prop.Int(480)
+			c.VideoEncoderBuilders = []codec.VideoEncoderBuilder{&vp8Params}
+		},
+	})
+	if err != nil {
+		panic(err)
+	}
+
+	select {}
+}
+
+type track struct {
+	codec      *webrtc.RTPCodec
+	packetizer rtp.Packetizer
+	id         string
+	conn       net.Conn
+}
+
+func newTrack(codec *webrtc.RTPCodec, id, dest string) *track {
+	addr, err := net.ResolveUDPAddr("udp", dest)
+	if err != nil {
+		panic(err)
+	}
+	conn, err := net.DialUDP("udp", nil, addr)
+	if err != nil {
+		panic(err)
+	}
+	return &track{
+		codec: codec,
+		packetizer: rtp.NewPacketizer(
+			mtu,
+			codec.PayloadType,
+			1,
+			codec.Payloader,
+			rtp.NewRandomSequencer(),
+			codec.ClockRate,
+		),
+		id:   id,
+		conn: conn,
+	}
+}
+
+func (t *track) WriteSample(s media.Sample) error {
+	buf := make([]byte, mtu)
+	pkts := t.packetizer.Packetize(s.Data, s.Samples)
+	for _, p := range pkts {
+		n, err := p.MarshalTo(buf)
+		if err != nil {
+			panic(err)
+		}
+		_, _ = t.conn.Write(buf[:n])
+	}
+	return nil
+}
+
+func (t *track) Codec() *webrtc.RTPCodec {
+	return t.codec
+}
+
+func (t *track) ID() string {
+	return t.id
+}
+
+func (t *track) Kind() webrtc.RTPCodecType {
+	return t.codec.Type
+}
--- a/examples/rtp-send/vp8.sdp
+++ b/examples/rtp-send/vp8.sdp
@@ -6,4 +6,4 @@ c=IN IP4 0.0.0.0
 t=0 0
 a=recvonly
 m=video 5000 RTP/AVP 100
-a=rtpmap:100 H264/90000
+a=rtpmap:100 VP8/90000
--- a/examples/rtp/README.md
+++ b/examples/rtp/README.md
@@ -1,38 +0,0 @@
-## Instructions
-
-### Install required codecs
-
-In this example, we'll be using x264 as our video codec. Therefore, we need to make sure that these codecs are installed within our system. 
-
-Installation steps:
-
-* [x264](https://github.com/pion/mediadevices#x264)
-
-### Download rtp example
-
-```
-git clone https://github.com/pion/mediadevices.git
-```
-
-### Listen RTP
-
-Install GStreamer and run:
-```
-gst-launch-1.0 udpsrc port=5000 caps=application/x-rtp,encode-name=H264 \
-    ! rtph264depay ! avdec_h264 ! videoconvert ! autovideosink
-```
-
-Or run VLC media plyer:
-```
-vlc ./h264.sdp
-```
-
-### Run rtp
-
-Run `cd mediadevices/examples/archive && go build && ./rtp localhost:5000`
-
-A video should start playing in your GStreamer or VLC window.
-It's not WebRTC, but pure RTP.
-
-Congrats, you have used pion-MediaDevices! Now start building something cool
-
--- a/examples/rtp/main.go
+++ b/examples/rtp/main.go
@@ -1,77 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"net"
-	"os"
-
-	"github.com/pion/mediadevices"
-	"github.com/pion/mediadevices/pkg/codec/x264"      // This is required to use H264 video encoder
-	_ "github.com/pion/mediadevices/pkg/driver/camera" // This is required to register camera adapter
-	"github.com/pion/mediadevices/pkg/frame"
-	"github.com/pion/mediadevices/pkg/prop"
-)
-
-const (
-	mtu = 1000
-)
-
-func must(err error) {
-	if err != nil {
-		panic(err)
-	}
-}
-
-func main() {
-	if len(os.Args) != 2 {
-		fmt.Printf("usage: %s host:port\n", os.Args[0])
-		return
-	}
-	dest := os.Args[1]
-
-	x264Params, err := x264.NewParams()
-	must(err)
-	x264Params.Preset = x264.PresetMedium
-	x264Params.BitRate = 1_000_000 // 1mbps
-
-	codecSelector := mediadevices.NewCodecSelector(
-		mediadevices.WithVideoEncoders(&x264Params),
-	)
-
-	mediaStream, err := mediadevices.GetUserMedia(mediadevices.MediaStreamConstraints{
-		Video: func(c *mediadevices.MediaTrackConstraints) {
-			c.FrameFormat = prop.FrameFormat(frame.FormatYUY2)
-			c.Width = prop.Int(640)
-			c.Height = prop.Int(480)
-		},
-		Codec: codecSelector,
-	})
-	must(err)
-
-	videoTrack := mediaStream.GetVideoTracks()[0]
-	defer videoTrack.Close()
-
-	rtpReader, err := videoTrack.NewRTPReader(x264Params.RTPCodec().Name, mtu)
-	must(err)
-
-	addr, err := net.ResolveUDPAddr("udp", dest)
-	must(err)
-	conn, err := net.DialUDP("udp", nil, addr)
-	must(err)
-
-	buff := make([]byte, mtu)
-	for {
-		pkts, release, err := rtpReader.Read()
-		must(err)
-
-		for _, pkt := range pkts {
-			n, err := pkt.MarshalTo(buff)
-			must(err)
-
-			_, err = conn.Write(buff[:n])
-			must(err)
-		}
-
-		release()
-	}
-}
--- a/examples/screenshare/README.md
+++ b/examples/screenshare/README.md
@@ -0,0 +1,29 @@
+## Instructions
+
+### Download screenshare
+
+```
+go get github.com/pion/mediadevices/examples/screenshare
+```
+
+### Open example page
+
+[jsfiddle.net](https://jsfiddle.net/gh/get/library/pure/pion/mediadevices/tree/master/examples/internal/jsfiddle/audio-and-video) you should see two text-areas and a 'Start Session' button
+
+### Run screenshare with your browsers SessionDescription as stdin
+
+In the jsfiddle the top textarea is your browser, copy that and:
+
+#### Linux
+
+Run `echo $BROWSER_SDP | screenshare`
+
+### Input screenshare's SessionDescription into your browser
+
+Copy the text that `screenshare` just emitted and copy into second text area
+
+### Hit 'Start Session' in jsfiddle, enjoy your video!
+
+A video should start playing in your browser above the input boxes, and will continue playing until you close the application.
+
+Congrats, you have used pion-WebRTC! Now start building something cool
--- a/examples/screenshare/main.go
+++ b/examples/screenshare/main.go
@@ -0,0 +1,101 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/pion/mediadevices"
+	"github.com/pion/mediadevices/examples/internal/signal"
+	"github.com/pion/mediadevices/pkg/codec"
+	"github.com/pion/mediadevices/pkg/codec/vpx"       // This is required to use VP8/VP9 video encoder
+	_ "github.com/pion/mediadevices/pkg/driver/screen" // This is required to register screen capture adapter
+	"github.com/pion/mediadevices/pkg/io/video"
+	"github.com/pion/webrtc/v2"
+)
+
+func main() {
+	config := webrtc.Configuration{
+		ICEServers: []webrtc.ICEServer{
+			{
+				URLs: []string{"stun:stun.l.google.com:19302"},
+			},
+		},
+	}
+
+	// Wait for the offer to be pasted
+	offer := webrtc.SessionDescription{}
+	signal.Decode(signal.MustReadStdin(), &offer)
+
+	// Create a new RTCPeerConnection
+	mediaEngine := webrtc.MediaEngine{}
+	if err := mediaEngine.PopulateFromSDP(offer); err != nil {
+		panic(err)
+	}
+	api := webrtc.NewAPI(webrtc.WithMediaEngine(mediaEngine))
+	peerConnection, err := api.NewPeerConnection(config)
+	if err != nil {
+		panic(err)
+	}
+
+	// Set the handler for ICE connection state
+	// This will notify you when the peer has connected/disconnected
+	peerConnection.OnICEConnectionStateChange(func(connectionState webrtc.ICEConnectionState) {
+		fmt.Printf("Connection State has changed %s \n", connectionState.String())
+	})
+
+	md := mediadevices.NewMediaDevices(peerConnection)
+
+	vp8Params, err := vpx.NewVP8Params()
+	if err != nil {
+		panic(err)
+	}
+	vp8Params.BitRate = 100000 // 100kbps
+
+	s, err := md.GetDisplayMedia(mediadevices.MediaStreamConstraints{
+		Video: func(c *mediadevices.MediaTrackConstraints) {
+			c.Enabled = true
+			c.VideoTransform = video.Scale(-1, 360, nil) // Resize to 360p
+			c.VideoEncoderBuilders = []codec.VideoEncoderBuilder{&vp8Params}
+		},
+	})
+	if err != nil {
+		panic(err)
+	}
+
+	for _, tracker := range s.GetTracks() {
+		t := tracker.Track()
+		tracker.OnEnded(func(err error) {
+			fmt.Printf("Track (ID: %s, Label: %s) ended with error: %v\n",
+				t.ID(), t.Label(), err)
+		})
+		_, err = peerConnection.AddTransceiverFromTrack(t,
+			webrtc.RtpTransceiverInit{
+				Direction: webrtc.RTPTransceiverDirectionSendonly,
+			},
+		)
+		if err != nil {
+			panic(err)
+		}
+	}
+
+	// Set the remote SessionDescription
+	err = peerConnection.SetRemoteDescription(offer)
+	if err != nil {
+		panic(err)
+	}
+
+	// Create an answer
+	answer, err := peerConnection.CreateAnswer(nil)
+	if err != nil {
+		panic(err)
+	}
+
+	// Sets the LocalDescription, and starts our UDP listeners
+	err = peerConnection.SetLocalDescription(answer)
+	if err != nil {
+		panic(err)
+	}
+
+	// Output the answer in base64 so we can paste it in browser
+	fmt.Println(signal.Encode(answer))
+	select {}
+}
--- a/examples/simple/README.md
+++ b/examples/simple/README.md
@@ -0,0 +1,29 @@
+## Instructions
+
+### Download gstreamer-send
+
+```
+go get github.com/pion/mediadevices/examples/simple
+```
+
+### Open example page
+
+[jsfiddle.net](https://jsfiddle.net/gh/get/library/pure/pion/mediadevices/tree/master/examples/internal/jsfiddle/audio-and-video) you should see two text-areas and a 'Start Session' button
+
+### Run simple with your browsers SessionDescription as stdin
+
+In the jsfiddle the top textarea is your browser, copy that and:
+
+#### Linux
+
+Run `echo $BROWSER_SDP | simple`
+
+### Input simple's SessionDescription into your browser
+
+Copy the text that `simple` just emitted and copy into second text area
+
+### Hit 'Start Session' in jsfiddle, enjoy your video!
+
+A video should start playing in your browser above the input boxes, and will continue playing until you close the application.
+
+Congrats, you have used pion-WebRTC! Now start building something cool
--- a/examples/simple/main.go
+++ b/examples/simple/main.go
@@ -5,18 +5,19 @@ import (

 	"github.com/pion/mediadevices"
 	"github.com/pion/mediadevices/examples/internal/signal"
+	"github.com/pion/mediadevices/pkg/codec"
 	"github.com/pion/mediadevices/pkg/frame"
 	"github.com/pion/mediadevices/pkg/prop"
 	"github.com/pion/webrtc/v2"

-	// If you don't like x264, you can also use vpx by importing as below
-	// "github.com/pion/mediadevices/pkg/codec/vpx" // This is required to use VP8/VP9 video encoder
+	// This is required to use opus audio encoder
+	"github.com/pion/mediadevices/pkg/codec/opus"
+
+	// If you don't like vpx, you can also use x264 by importing as below
+	// "github.com/pion/mediadevices/pkg/codec/x264" // This is required to use h264 video encoder
 	// or you can also use openh264 for alternative h264 implementation
 	// "github.com/pion/mediadevices/pkg/codec/openh264"
-	// or if you use a raspberry pi like, you can use mmal for using its hardware encoder
-	// "github.com/pion/mediadevices/pkg/codec/mmal"
-	"github.com/pion/mediadevices/pkg/codec/opus" // This is required to use opus audio encoder
-	"github.com/pion/mediadevices/pkg/codec/x264" // This is required to use h264 video encoder
+	"github.com/pion/mediadevices/pkg/codec/vpx" // This is required to use VP8/VP9 video encoder

 	// Note: If you don't have a camera or microphone or your adapters are not supported,
 	//       you can always swap your adapters with our dummy adapters below.
@@ -26,6 +27,10 @@ import (
 	_ "github.com/pion/mediadevices/pkg/driver/microphone" // This is required to register microphone adapter
 )

+const (
+	videoCodecName = webrtc.VP8
+)
+
 func main() {
 	config := webrtc.Configuration{
 		ICEServers: []webrtc.ICEServer{
@@ -40,23 +45,7 @@ func main() {
 	signal.Decode(signal.MustReadStdin(), &offer)

 	// Create a new RTCPeerConnection
-	x264Params, err := x264.NewParams()
-	if err != nil {
-		panic(err)
-	}
-	x264Params.BitRate = 500_000 // 500kbps
-
-	opusParams, err := opus.NewParams()
-	if err != nil {
-		panic(err)
-	}
-	codecSelector := mediadevices.NewCodecSelector(
-		mediadevices.WithVideoEncoders(&x264Params),
-		mediadevices.WithAudioEncoders(&opusParams),
-	)
-
 	mediaEngine := webrtc.MediaEngine{}
-	codecSelector.Populate(&mediaEngine)
 	if err := mediaEngine.PopulateFromSDP(offer); err != nil {
 		panic(err)
 	}
@@ -72,33 +61,44 @@ func main() {
 		fmt.Printf("Connection State has changed %s \n", connectionState.String())
 	})

-	s, err := mediadevices.GetUserMedia(mediadevices.MediaStreamConstraints{
+	md := mediadevices.NewMediaDevices(peerConnection)
+
+	opusParams, err := opus.NewParams()
+	if err != nil {
+		panic(err)
+	}
+	opusParams.BitRate = 32000 // 32kbps
+
+	vp8Params, err := vpx.NewVP8Params()
+	if err != nil {
+		panic(err)
+	}
+	vp8Params.BitRate = 100000 // 100kbps
+
+	s, err := md.GetUserMedia(mediadevices.MediaStreamConstraints{
+		Audio: func(c *mediadevices.MediaTrackConstraints) {
+			c.Enabled = true
+			c.AudioEncoderBuilders = []codec.AudioEncoderBuilder{&opusParams}
+		},
 		Video: func(c *mediadevices.MediaTrackConstraints) {
 			c.FrameFormat = prop.FrameFormat(frame.FormatYUY2)
+			c.Enabled = true
 			c.Width = prop.Int(640)
 			c.Height = prop.Int(480)
+			c.VideoEncoderBuilders = []codec.VideoEncoderBuilder{&vp8Params}
 		},
-		Audio: func(c *mediadevices.MediaTrackConstraints) {
-		},
-		Codec: codecSelector,
 	})
 	if err != nil {
 		panic(err)
 	}

 	for _, tracker := range s.GetTracks() {
+		t := tracker.Track()
 		tracker.OnEnded(func(err error) {
-			fmt.Printf("Track (ID: %s) ended with error: %v\n",
-				tracker.ID(), err)
+			fmt.Printf("Track (ID: %s, Label: %s) ended with error: %v\n",
+				t.ID(), t.Label(), err)
 		})
-
-		// In Pion/webrtc v3, bind will be called automatically after SDP negotiation
-		webrtcTrack, err := tracker.Bind(peerConnection)
-		if err != nil {
-			panic(err)
-		}
-
-		_, err = peerConnection.AddTransceiverFromTrack(webrtcTrack,
+		_, err = peerConnection.AddTransceiverFromTrack(t,
 			webrtc.RtpTransceiverInit{
 				Direction: webrtc.RTPTransceiverDirectionSendonly,
 			},
--- a/examples/webrtc/README.md
+++ b/examples/webrtc/README.md
@@ -1,42 +0,0 @@
-## Instructions
-
-### Install required codecs
-
-In this example, we'll be using x264 and opus as our video and audio codecs. Therefore, we need to make sure that these codecs are installed within our system. 
-
-Installation steps:
-
-* [x264](https://github.com/pion/mediadevices#x264)
-* [opus](https://github.com/pion/mediadevices#opus)
-
-### Download webrtc example
-
-```
-git clone https://github.com/pion/mediadevices.git
-```
-
-#### Compile webrtc example
-
-```
-cd mediadevices/examples/webrtc && go build
-```
-
-### Open example page
-
-[jsfiddle.net](https://jsfiddle.net/gh/get/library/pure/pion/mediadevices/tree/master/examples/internal/jsfiddle/audio-and-video) you should see two text-areas and a 'Start Session' button
-
-### Run the webrtc example with your browsers SessionDescription as stdin
-
-In the jsfiddle the top textarea is your browser, copy that, and store the session description in an environment variable, `export SDP=<put_the_sdp_here>`
-
-Run `echo $SDP | ./webrtc`
-
-### Input webrtc's SessionDescription into your browser
-
-Copy the text that `./webrtc` just emitted and copy into second text area
-
-### Hit 'Start Session' in jsfiddle, enjoy your video!
-
-A video should start playing in your browser above the input boxes, and will continue playing until you close the application.
-
-Congrats, you have used pion-MediaDevices! Now start building something cool
--- a/go.mod
+++ b/go.mod
@@ -3,17 +3,11 @@ module github.com/pion/mediadevices
 go 1.13

 require (
-	github.com/BurntSushi/xgb v0.0.0-20201008132610-5f9e7b3c49cd // indirect
 	github.com/blackjack/webcam v0.0.0-20200313125108-10ed912a8539
-	github.com/gen2brain/malgo v0.10.25
-	github.com/gen2brain/shm v0.0.0-20200228170931-49f9650110c5 // indirect
-	github.com/kbinani/screenshot v0.0.0-20191211154542-3a185f1ce18f
-	github.com/lherman-cs/opus v0.0.2
-	github.com/lxn/win v0.0.0-20201111105847-2a20daff6a55 // indirect
-	github.com/pion/logging v0.2.2
-	github.com/pion/rtp v1.6.1
-	github.com/pion/webrtc/v2 v2.2.26
+	github.com/jfreymuth/pulse v0.0.0-20200817093420-a82ccdb5e8aa
+	github.com/lherman-cs/opus v0.0.0-20200223204610-6a4b98199ea4
+	github.com/pion/webrtc/v2 v2.2.24
 	github.com/satori/go.uuid v1.2.0
-	golang.org/x/image v0.0.0-20200927104501-e162460cd6b5
-	golang.org/x/sys v0.0.0-20201029080932-201ba4db2418 // indirect
+	golang.org/x/image v0.0.0-20200801110659-972c09e46d76
+	golang.org/x/sys v0.0.0-20200831180312-196b9ba8737a
 )
--- a/go.sum
+++ b/go.sum
@@ -1,5 +1,3 @@
-github.com/BurntSushi/xgb v0.0.0-20201008132610-5f9e7b3c49cd h1:u7K2oMFMd8APDV3fM1j2rO3U/XJf1g1qC3DDTKou8iM=
-github.com/BurntSushi/xgb v0.0.0-20201008132610-5f9e7b3c49cd/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
 github.com/blackjack/webcam v0.0.0-20200313125108-10ed912a8539 h1:1aIqYfg9s9RETAJHGfVKZW4ok0b22p4QTwk8MsdRtPs=
 github.com/blackjack/webcam v0.0.0-20200313125108-10ed912a8539/go.mod h1:G0X+rEqYPWSq0dG8OMf8M446MtKytzpPjgS3HbdOJZ4=
 github.com/cheekybits/genny v1.0.0 h1:uGGa4nei+j20rOSeDeP5Of12XVm7TGUd4dJA9RDitfE=
@@ -9,10 +7,6 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
-github.com/gen2brain/malgo v0.10.25 h1:VRiYTBmBeHTCXD0wCg7XyLi6lJJBqND/XVmSEyrGkGc=
-github.com/gen2brain/malgo v0.10.25/go.mod h1:zHSUNZAXfCeNsZou0RtQ6Zk7gDYLIcKOrUWtAdksnEs=
-github.com/gen2brain/shm v0.0.0-20200228170931-49f9650110c5 h1:Y5Q2mEwfzjMt5+3u70Gtw93ZOu2UuPeeeTBDntF7FoY=
-github.com/gen2brain/shm v0.0.0-20200228170931-49f9650110c5/go.mod h1:uF6rMu/1nvu+5DpiRLwusA6xB8zlkNoGzKn8lmYONUo=
 github.com/golang/mock v1.2.0 h1:28o5sBqPkBsMGnC6b4MvE2TzSr5/AT4c/1fLqVGIwlk=
 github.com/golang/mock v1.2.0/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
 github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
@@ -21,19 +15,17 @@ github.com/google/uuid v1.1.1 h1:Gkbcsh/GbpXz7lPftLA3P6TYMwjCLYm83jiFQZF/3gY=
 github.com/google/uuid v1.1.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/hpcloud/tail v1.0.0 h1:nfCOvKYfkgYP8hkirhJocXT2+zOD8yUNjXaWfTlyFKI=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
-github.com/kbinani/screenshot v0.0.0-20191211154542-3a185f1ce18f h1:5hWo+DzJQSOBl6X+TDac0SPWffRonuRJ2///OYtYRT8=
-github.com/kbinani/screenshot v0.0.0-20191211154542-3a185f1ce18f/go.mod h1:f8GY5V3lRzakvEyr49P7hHRYoHtPr8zvj/7JodCoRzw=
+github.com/jfreymuth/pulse v0.0.0-20200817093420-a82ccdb5e8aa h1:qUZIj5+D3UDgfshNe8Cz/9maOxe8ddt43qwQH9vEEC8=
+github.com/jfreymuth/pulse v0.0.0-20200817093420-a82ccdb5e8aa/go.mod h1:cpYspI6YljhkUf1WLXLLDmeaaPFc3CnGLjDZf9dZ4no=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
-github.com/lherman-cs/opus v0.0.2 h1:fE9Du3NKXDBztqvoTd6P2y9eJ9vgIHahGK8yQostnhA=
-github.com/lherman-cs/opus v0.0.2/go.mod h1:v9KQvlDYMuvlwniumBVMlrB0VHQvyTgxNvaXjPmTmps=
+github.com/lherman-cs/opus v0.0.0-20200223204610-6a4b98199ea4 h1:2ydMA2KbxRkYmIw3R8Me8dn90bejxBR4MKYXJ5THK3I=
+github.com/lherman-cs/opus v0.0.0-20200223204610-6a4b98199ea4/go.mod h1:v9KQvlDYMuvlwniumBVMlrB0VHQvyTgxNvaXjPmTmps=
 github.com/lucas-clemente/quic-go v0.7.1-0.20190401152353-907071221cf9 h1:tbuodUh2vuhOVZAdW3NEUvosFHUMJwUNl7jk/VSEiwc=
 github.com/lucas-clemente/quic-go v0.7.1-0.20190401152353-907071221cf9/go.mod h1:PpMmPfPKO9nKJ/psF49ESTAGQSdfXxlg1otPbEB2nOw=
-github.com/lxn/win v0.0.0-20201111105847-2a20daff6a55 h1:4BxFx5XCtXc+nFtXDGDW+Uu5sPtsAbvPh6RObj3fG9o=
-github.com/lxn/win v0.0.0-20201111105847-2a20daff6a55/go.mod h1:KxxjdtRkfNoYDCUP5ryK7XJJNTnpC8atvtmTheChOtk=
 github.com/marten-seemann/qtls v0.2.3 h1:0yWJ43C62LsZt08vuQJDK1uC1czUc3FJeCLPoNAI4vA=
 github.com/marten-seemann/qtls v0.2.3/go.mod h1:xzjG7avBwGGbdZ8dTGxlBnLArsVKLvwmjgmPuiQEcYk=
 github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
@@ -41,8 +33,9 @@ github.com/onsi/ginkgo v1.7.0 h1:WSHQ+IS43OoUrWtD1/bbclrwK8TTH5hzp+umCiuxHgs=
 github.com/onsi/ginkgo v1.7.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/gomega v1.4.3 h1:RE1xgDvH7imwFD45h+u2SgIfERHlS2yNG4DObb5BSKU=
 github.com/onsi/gomega v1.4.3/go.mod h1:ex+gbHU/CVuBBDIJjb2X0qEXbFg53c61hWP/1CpauHY=
-github.com/pion/datachannel v1.4.21 h1:3ZvhNyfmxsAqltQrApLPQMhSFNA+aT87RqyCq4OXmf0=
-github.com/pion/datachannel v1.4.21/go.mod h1:oiNyP4gHx2DIwRzX/MFyH0Rz/Gz05OgBlayAI2hAWjg=
+github.com/pion/datachannel v1.4.20 h1:+uYUrxbhGuEt+9En81Necda5ul8M2h7mMsvGWkYZ/yI=
+github.com/pion/datachannel v1.4.20/go.mod h1:hsjWYdTW5fMmtM4hVIxUNYqViRPv2A6ixzkQFd82wSc=
+github.com/pion/dtls/v2 v2.0.1 h1:ddE7+V0faYRbyh4uPsRZ2vLdRrjVZn+wmCfI7jlBfaA=
 github.com/pion/dtls/v2 v2.0.1/go.mod h1:uMQkz2W0cSqY00xav7WByQ4Hb+18xeQh2oH2fRezr5U=
 github.com/pion/dtls/v2 v2.0.2 h1:FHCHTiM182Y8e15aFTiORroiATUI16ryHiQh8AIOJ1E=
 github.com/pion/dtls/v2 v2.0.2/go.mod h1:27PEO3MDdaCfo21heT59/vsdmZc0zMt9wQPcSlLu/1I=
@@ -61,10 +54,8 @@ github.com/pion/rtcp v1.2.3 h1:2wrhKnqgSz91Q5nzYTO07mQXztYPtxL8a0XOss4rJqA=
 github.com/pion/rtcp v1.2.3/go.mod h1:zGhIv0RPRF0Z1Wiij22pUt5W/c9fevqSzT4jje/oK7I=
 github.com/pion/rtp v1.6.0 h1:4Ssnl/T5W2LzxHj9ssYpGVEQh3YYhQFNVmSWO88MMwk=
 github.com/pion/rtp v1.6.0/go.mod h1:QgfogHsMBVE/RFNno467U/KBqfUywEH+HK+0rtnwsdI=
-github.com/pion/rtp v1.6.1 h1:2Y2elcVBrahYnHKN2X7rMHX/r1R4TEBMP1LaVu/wNhk=
-github.com/pion/rtp v1.6.1/go.mod h1:bDb5n+BFZxXx0Ea7E5qe+klMuqiBrP+w8XSjiWtCUko=
-github.com/pion/sctp v1.7.10 h1:o3p3/hZB5Cx12RMGyWmItevJtZ6o2cpuxaw6GOS4x+8=
-github.com/pion/sctp v1.7.10/go.mod h1:EhpTUQu1/lcK3xI+eriS6/96fWetHGCvBi9MSsnaBN0=
+github.com/pion/sctp v1.7.9 h1:n+A37cTMU08xL3Oodkz39XjtPReQliKyk01q96mGB5M=
+github.com/pion/sctp v1.7.9/go.mod h1:EhpTUQu1/lcK3xI+eriS6/96fWetHGCvBi9MSsnaBN0=
 github.com/pion/sdp/v2 v2.4.0 h1:luUtaETR5x2KNNpvEMv/r4Y+/kzImzbz4Lm1z8eQNQI=
 github.com/pion/sdp/v2 v2.4.0/go.mod h1:L2LxrOpSTJbAns244vfPChbciR/ReU1KWfG04OpkR7E=
 github.com/pion/srtp v1.5.1 h1:9Q3jAfslYZBt+C69SI/ZcONJh9049JUHZWYRRf5KEKw=
@@ -72,7 +63,9 @@ github.com/pion/srtp v1.5.1/go.mod h1:B+QgX5xPeQTNc1CJStJPHzOlHK66ViMDWTT0HZTCkc
 github.com/pion/stun v0.3.5 h1:uLUCBCkQby4S1cf6CGuR9QrVOKcvUwFeemaC865QHDg=
 github.com/pion/stun v0.3.5/go.mod h1:gDMim+47EeEtfWogA37n6qXZS88L5V6LqFcf+DZA2UA=
 github.com/pion/transport v0.6.0/go.mod h1:iWZ07doqOosSLMhZ+FXUTq+TamDoXSllxpbGcfkCmbE=
+github.com/pion/transport v0.8.10 h1:lTiobMEw2PG6BH/mgIVqTV2mBp/mPT+IJLaN8ZxgdHk=
 github.com/pion/transport v0.8.10/go.mod h1:tBmha/UCjpum5hqTWhfAEs3CO4/tHSg0MYRhSzR+CZ8=
+github.com/pion/transport v0.10.0 h1:9M12BSneJm6ggGhJyWpDveFOstJsTiQjkLf4M44rm80=
 github.com/pion/transport v0.10.0/go.mod h1:BnHnUipd0rZQyTVB2SBGojFHT9CBt5C5TcsJSQGkvSE=
 github.com/pion/transport v0.10.1 h1:2W+yJT+0mOQ160ThZYUx5Zp2skzshiNgxrNE9GUfhJM=
 github.com/pion/transport v0.10.1/go.mod h1:PBis1stIILMiis0PewDw91WJeLJkyIMcEk+DwKOzf4A=
@@ -80,8 +73,8 @@ github.com/pion/turn/v2 v2.0.4 h1:oDguhEv2L/4rxwbL9clGLgtzQPjtuZwCdoM7Te8vQVk=
 github.com/pion/turn/v2 v2.0.4/go.mod h1:1812p4DcGVbYVBTiraUmP50XoKye++AMkbfp+N27mog=
 github.com/pion/udp v0.1.0 h1:uGxQsNyrqG3GLINv36Ff60covYmfrLoxzwnCsIYspXI=
 github.com/pion/udp v0.1.0/go.mod h1:BPELIjbwE9PRbd/zxI/KYBnbo7B6+oA6YuEaNE8lths=
-github.com/pion/webrtc/v2 v2.2.26 h1:01hWE26pL3LgqfxvQ1fr6O4ZtyRFFJmQEZK39pHWfFc=
-github.com/pion/webrtc/v2 v2.2.26/go.mod h1:XMZbZRNHyPDe1gzTIHFcQu02283YO45CbiwFgKvXnmc=
+github.com/pion/webrtc/v2 v2.2.24 h1:l7q/iO96tMTElxuE2XGdNhCzklGcd9aVZ00XufASp0g=
+github.com/pion/webrtc/v2 v2.2.24/go.mod h1:U/m+nvG1t8gInf8PwiDyJEDcd7qfl+jmGQXqTX2zGvo=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -91,23 +84,29 @@ github.com/satori/go.uuid v1.2.0/go.mod h1:dA0hQrYB0VpLJoorglMZABFdXlWrHn1NEOzdh
 github.com/sclevine/agouti v3.0.0+incompatible/go.mod h1:b4WX9W9L1sfQKXeJf1mUTLZKJ48R1S7H23Ji7oFO5Bw=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 golang.org/x/crypto v0.0.0-20190228161510-8dd112bcdc25/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20200602180216-279210d13fed h1:g4KENRiCMEx58Q7/ecwfT0N2o8z35Fnbsjig/Alf2T4=
 golang.org/x/crypto v0.0.0-20200602180216-279210d13fed/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9 h1:psW17arqaxU48Z5kZ0CQnkZWQJsqcURM6tKiBApRjXI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20200709230013-948cd5f35899 h1:DZhuSZLsGlFL4CmhA8BcRA0mnthyA/nZ00AqCUo7vHg=
 golang.org/x/crypto v0.0.0-20200709230013-948cd5f35899/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/image v0.0.0-20200927104501-e162460cd6b5 h1:QelT11PB4FXiDEXucrfNckHoFxwt8USGY1ajP1ZF5lM=
-golang.org/x/image v0.0.0-20200927104501-e162460cd6b5/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
+golang.org/x/image v0.0.0-20200801110659-972c09e46d76 h1:U7GPaoQyQmX+CBRWXKrvRzWTbd+slqeSh8uARsIyhAw=
+golang.org/x/image v0.0.0-20200801110659-972c09e46d76/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20191126235420-ef20fe5d7933/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20200602114024-627f9648deb9 h1:pNX+40auqi2JqRfOP1akLGtYcn15TUbkhwuCO3foqqM=
 golang.org/x/net v0.0.0-20200602114024-627f9648deb9/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
+golang.org/x/net v0.0.0-20200625001655-4c5254603344 h1:vGXIOMxbNfDTk/aXCmfdLgkrSV+Z2tcbze+pEc3v5W4=
 golang.org/x/net v0.0.0-20200625001655-4c5254603344/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
 golang.org/x/net v0.0.0-20200707034311-ab3426394381 h1:VXak5I6aEWmAXeQjA+QSZzlgNrpq9mjcfDemuexIKsU=
 golang.org/x/net v0.0.0-20200707034311-ab3426394381/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
@@ -118,10 +117,10 @@ golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5h
 golang.org/x/sys v0.0.0-20190228124157-a34e9553db1e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200724161237-0e2f3a69832c h1:UIcGWL6/wpCfyGuJnRFJRurA+yj8RrW7Q6x2YMCXt6c=
 golang.org/x/sys v0.0.0-20200724161237-0e2f3a69832c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20201018230417-eeed37f84f13/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20201029080932-201ba4db2418 h1:HlFl4V6pEMziuLXyRkm5BIYq1y1GAbb02pRlWvI54OM=
-golang.org/x/sys v0.0.0-20201029080932-201ba4db2418/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200831180312-196b9ba8737a h1:i47hUS795cOydZI4AwJQCKXOr4BvxzvikwDoDtHhP2Y=
+golang.org/x/sys v0.0.0-20200831180312-196b9ba8737a/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
--- a/img/demo.gif
+++ b/img/demo.gif
--- a/internal/logging/logging.go
+++ b/internal/logging/logging.go
@@ -1,11 +0,0 @@
-package logging
-
-import (
-	"github.com/pion/logging"
-)
-
-var loggerFactory = logging.NewDefaultLoggerFactory()
-
-func NewLogger(scope string) logging.LeveledLogger {
-	return loggerFactory.NewLogger(scope)
-}
--- a/ioreader.go
+++ b/ioreader.go
@@ -1,14 +0,0 @@
-package mediadevices
-
-type encodedReadCloserImpl struct {
-	readFn  func([]byte) (int, error)
-	closeFn func() error
-}
-
-func (r *encodedReadCloserImpl) Read(b []byte) (int, error) {
-	return r.readFn(b)
-}
-
-func (r *encodedReadCloserImpl) Close() error {
-	return r.closeFn()
-}
--- a/logging.go
+++ b/logging.go
@@ -1,7 +0,0 @@
-package mediadevices
-
-import (
-	"github.com/pion/mediadevices/internal/logging"
-)
-
-var logger = logging.NewLogger("mediadevices")
--- a/mediadeviceinfo.go
+++ b/mediadeviceinfo.go
@@ -7,7 +7,7 @@ type MediaDeviceType int

 // MediaDeviceType definitions.
 const (
-	VideoInput MediaDeviceType = iota + 1
+	VideoInput MediaDeviceType = iota
 	AudioInput
 	AudioOutput
 )
--- a/mediadevices.go
+++ b/mediadevices.go
@@ -3,30 +3,98 @@ package mediadevices
 import (
 	"fmt"
 	"math"
-	"strings"

 	"github.com/pion/mediadevices/pkg/driver"
 	"github.com/pion/mediadevices/pkg/prop"
+	"github.com/pion/webrtc/v2"
 )

 var errNotFound = fmt.Errorf("failed to find the best driver that fits the constraints")

+// MediaDevices is an interface that's defined on https://developer.mozilla.org/en-US/docs/Web/API/MediaDevices
+type MediaDevices interface {
+	GetDisplayMedia(constraints MediaStreamConstraints) (MediaStream, error)
+	GetUserMedia(constraints MediaStreamConstraints) (MediaStream, error)
+	EnumerateDevices() []MediaDeviceInfo
+}
+
+// NewMediaDevices creates MediaDevices interface that provides access to connected media input devices
+// like cameras and microphones, as well as screen sharing.
+// In essence, it lets you obtain access to any hardware source of media data.
+func NewMediaDevices(pc *webrtc.PeerConnection, opts ...MediaDevicesOption) MediaDevices {
+	codecs := make(map[webrtc.RTPCodecType][]*webrtc.RTPCodec)
+	for _, kind := range []webrtc.RTPCodecType{
+		webrtc.RTPCodecTypeAudio,
+		webrtc.RTPCodecTypeVideo,
+	} {
+		codecs[kind] = pc.GetRegisteredRTPCodecs(kind)
+	}
+	return NewMediaDevicesFromCodecs(codecs, opts...)
+}
+
+// NewMediaDevicesFromCodecs creates MediaDevices interface from lists of the available codecs
+// that provides access to connected media input devices like cameras and microphones,
+// as well as screen sharing.
+// In essence, it lets you obtain access to any hardware source of media data.
+func NewMediaDevicesFromCodecs(codecs map[webrtc.RTPCodecType][]*webrtc.RTPCodec, opts ...MediaDevicesOption) MediaDevices {
+	mdo := MediaDevicesOptions{
+		codecs:         codecs,
+		trackGenerator: defaultTrackGenerator,
+	}
+	for _, o := range opts {
+		o(&mdo)
+	}
+	return &mediaDevices{
+		MediaDevicesOptions: mdo,
+	}
+}
+
+// TrackGenerator is a function to create new track.
+type TrackGenerator func(payloadType uint8, ssrc uint32, id, label string, codec *webrtc.RTPCodec) (LocalTrack, error)
+
+var defaultTrackGenerator = TrackGenerator(func(pt uint8, ssrc uint32, id, label string, codec *webrtc.RTPCodec) (LocalTrack, error) {
+	return webrtc.NewTrack(pt, ssrc, id, label, codec)
+})
+
+type mediaDevices struct {
+	MediaDevicesOptions
+}
+
+// MediaDevicesOptions stores parameters used by MediaDevices.
+type MediaDevicesOptions struct {
+	codecs         map[webrtc.RTPCodecType][]*webrtc.RTPCodec
+	trackGenerator TrackGenerator
+}
+
+// MediaDevicesOption is a type of MediaDevices functional option.
+type MediaDevicesOption func(*MediaDevicesOptions)
+
+// WithTrackGenerator specifies a TrackGenerator to use customized track.
+func WithTrackGenerator(gen TrackGenerator) MediaDevicesOption {
+	return func(o *MediaDevicesOptions) {
+		o.trackGenerator = gen
+	}
+}
+
 // GetDisplayMedia prompts the user to select and grant permission to capture the contents
 // of a display or portion thereof (such as a window) as a MediaStream.
 // Reference: https://developer.mozilla.org/en-US/docs/Web/API/MediaDevices/getDisplayMedia
-func GetDisplayMedia(constraints MediaStreamConstraints) (MediaStream, error) {
-	trackers := make([]Track, 0)
+func (m *mediaDevices) GetDisplayMedia(constraints MediaStreamConstraints) (MediaStream, error) {
+	trackers := make([]Tracker, 0)

 	cleanTrackers := func() {
 		for _, t := range trackers {
-			t.Close()
+			t.Stop()
 		}
 	}

 	var videoConstraints MediaTrackConstraints
 	if constraints.Video != nil {
 		constraints.Video(&videoConstraints)
-		tracker, err := selectScreen(videoConstraints, constraints.Codec)
+	}
+
+	if videoConstraints.Enabled {
+		tracker, err := m.selectScreen(videoConstraints)
 		if err != nil {
 			cleanTrackers()
 			return nil, err
@@ -47,20 +115,27 @@ func GetDisplayMedia(constraints MediaStreamConstraints) (MediaStream, error) {
 // GetUserMedia prompts the user for permission to use a media input which produces a MediaStream
 // with tracks containing the requested types of media.
 // Reference: https://developer.mozilla.org/en-US/docs/Web/API/MediaDevices/getUserMedia
-func GetUserMedia(constraints MediaStreamConstraints) (MediaStream, error) {
+func (m *mediaDevices) GetUserMedia(constraints MediaStreamConstraints) (MediaStream, error) {
 	// TODO: It should return media stream based on constraints
-	trackers := make([]Track, 0)
+	trackers := make([]Tracker, 0)

 	cleanTrackers := func() {
 		for _, t := range trackers {
-			t.Close()
+			t.Stop()
 		}
 	}

 	var videoConstraints, audioConstraints MediaTrackConstraints
 	if constraints.Video != nil {
 		constraints.Video(&videoConstraints)
-		tracker, err := selectVideo(videoConstraints, constraints.Codec)
+	}
+
+	if constraints.Audio != nil {
+		constraints.Audio(&audioConstraints)
+	}
+
+	if videoConstraints.Enabled {
+		tracker, err := m.selectVideo(videoConstraints)
 		if err != nil {
 			cleanTrackers()
 			return nil, err
@@ -69,9 +144,8 @@ func GetUserMedia(constraints MediaStreamConstraints) (MediaStream, error) {
 		trackers = append(trackers, tracker)
 	}

-	if constraints.Audio != nil {
-		constraints.Audio(&audioConstraints)
-		tracker, err := selectAudio(audioConstraints, constraints.Codec)
+	if audioConstraints.Enabled {
+		tracker, err := m.selectAudio(audioConstraints)
 		if err != nil {
 			cleanTrackers()
 			return nil, err
@@ -120,15 +194,12 @@ func queryDriverProperties(filter driver.FilterFn) map[driver.Driver][]prop.Medi
 func selectBestDriver(filter driver.FilterFn, constraints MediaTrackConstraints) (driver.Driver, MediaTrackConstraints, error) {
 	var bestDriver driver.Driver
 	var bestProp prop.Media
-	var foundPropertiesLog []string
 	minFitnessDist := math.Inf(1)

-	foundPropertiesLog = append(foundPropertiesLog, "\n============ Found Properties ============")
 	driverProperties := queryDriverProperties(filter)
 	for d, props := range driverProperties {
 		priority := float64(d.Info().Priority)
 		for _, p := range props {
-			foundPropertiesLog = append(foundPropertiesLog, p.String())
 			fitnessDist, ok := constraints.MediaConstraints.FitnessDistance(p)
 			if !ok {
 				continue
@@ -142,25 +213,17 @@ func selectBestDriver(filter driver.FilterFn, constraints MediaTrackConstraints)
 		}
 	}

-	foundPropertiesLog = append(foundPropertiesLog, "=============== Constraints ==============")
-	foundPropertiesLog = append(foundPropertiesLog, constraints.String())
-	foundPropertiesLog = append(foundPropertiesLog, "================ Best Fit ================")
-
 	if bestDriver == nil {
-		foundPropertiesLog = append(foundPropertiesLog, "Not found")
-		logger.Debug(strings.Join(foundPropertiesLog, "\n\n"))
 		return nil, MediaTrackConstraints{}, errNotFound
 	}

-	foundPropertiesLog = append(foundPropertiesLog, bestProp.String())
-	logger.Debug(strings.Join(foundPropertiesLog, "\n\n"))
 	constraints.selectedMedia = prop.Media{}
 	constraints.selectedMedia.MergeConstraints(constraints.MediaConstraints)
 	constraints.selectedMedia.Merge(bestProp)
 	return bestDriver, constraints, nil
 }

-func selectAudio(constraints MediaTrackConstraints, selector *CodecSelector) (Track, error) {
+func (m *mediaDevices) selectAudio(constraints MediaTrackConstraints) (Tracker, error) {
 	typeFilter := driver.FilterAudioRecorder()

 	d, c, err := selectBestDriver(typeFilter, constraints)
@@ -168,9 +231,9 @@ func selectAudio(constraints MediaTrackConstraints, selector *CodecSelector) (Tr
 		return nil, err
 	}

-	return newTrackFromDriver(d, c, selector)
+	return newTrack(&m.MediaDevicesOptions, d, c)
 }
-func selectVideo(constraints MediaTrackConstraints, selector *CodecSelector) (Track, error) {
+func (m *mediaDevices) selectVideo(constraints MediaTrackConstraints) (Tracker, error) {
 	typeFilter := driver.FilterVideoRecorder()
 	notScreenFilter := driver.FilterNot(driver.FilterDeviceType(driver.Screen))
 	filter := driver.FilterAnd(typeFilter, notScreenFilter)
@@ -180,10 +243,10 @@ func selectVideo(constraints MediaTrackConstraints, selector *CodecSelector) (Tr
 		return nil, err
 	}

-	return newTrackFromDriver(d, c, selector)
+	return newTrack(&m.MediaDevicesOptions, d, c)
 }

-func selectScreen(constraints MediaTrackConstraints, selector *CodecSelector) (Track, error) {
+func (m *mediaDevices) selectScreen(constraints MediaTrackConstraints) (Tracker, error) {
 	typeFilter := driver.FilterVideoRecorder()
 	screenFilter := driver.FilterDeviceType(driver.Screen)
 	filter := driver.FilterAnd(typeFilter, screenFilter)
@@ -193,10 +256,10 @@ func selectScreen(constraints MediaTrackConstraints, selector *CodecSelector) (T
 		return nil, err
 	}

-	return newTrackFromDriver(d, c, selector)
+	return newTrack(&m.MediaDevicesOptions, d, c)
 }

-func EnumerateDevices() []MediaDeviceInfo {
+func (m *mediaDevices) EnumerateDevices() []MediaDeviceInfo {
 	drivers := driver.GetManager().Query(
 		driver.FilterFn(func(driver.Driver) bool { return true }))
 	info := make([]MediaDeviceInfo, 0, len(drivers))
--- a/mediadevices_bench_test.go
+++ b/mediadevices_bench_test.go
@@ -1,82 +0,0 @@
-// +build e2e
-
-package mediadevices
-
-import (
-	"image"
-	"sync"
-	"testing"
-
-	"github.com/pion/mediadevices/pkg/codec/x264"
-	"github.com/pion/mediadevices/pkg/frame"
-)
-
-type mockVideoSource struct {
-	width, height int
-	pool          sync.Pool
-	decoder       frame.Decoder
-}
-
-func newMockVideoSource(width, height int) *mockVideoSource {
-	decoder, err := frame.NewDecoder(frame.FormatYUY2)
-	if err != nil {
-		panic(err)
-	}
-
-	return &mockVideoSource{
-		width:  width,
-		height: height,
-		pool: sync.Pool{
-			New: func() interface{} {
-				resolution := width * height
-				return make([]byte, resolution*2)
-			},
-		},
-		decoder: decoder,
-	}
-}
-
-func (source *mockVideoSource) ID() string   { return "" }
-func (source *mockVideoSource) Close() error { return nil }
-func (source *mockVideoSource) Read() (image.Image, func(), error) {
-	raw := source.pool.Get().([]byte)
-	decoded, release, err := source.decoder.Decode(raw, source.width, source.height)
-	source.pool.Put(raw)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	return decoded, release, nil
-}
-
-func BenchmarkEndToEnd(b *testing.B) {
-	params, err := x264.NewParams()
-	if err != nil {
-		b.Fatal(err)
-	}
-	params.BitRate = 300_000
-
-	videoSource := newMockVideoSource(1920, 1080)
-	track := NewVideoTrack(videoSource, nil).(*VideoTrack)
-	defer track.Close()
-
-	reader := track.NewReader(false)
-	inputProp, err := detectCurrentVideoProp(track.Broadcaster)
-	if err != nil {
-		b.Fatal(err)
-	}
-
-	encodedReader, err := params.BuildVideoEncoder(reader, inputProp)
-	if err != nil {
-		b.Fatal(err)
-	}
-	defer encodedReader.Close()
-
-	for i := 0; i < b.N; i++ {
-		_, release, err := encodedReader.Read()
-		if err != nil {
-			b.Fatal(err)
-		}
-		release()
-	}
-}
--- a/mediadevices_test.go
+++ b/mediadevices_test.go
@@ -1,42 +1,91 @@
 package mediadevices

 import (
+	"errors"
 	"io"
 	"testing"
 	"time"

+	"github.com/pion/webrtc/v2"
+	"github.com/pion/webrtc/v2/pkg/media"
+
+	"github.com/pion/mediadevices/pkg/codec"
 	"github.com/pion/mediadevices/pkg/driver"
 	_ "github.com/pion/mediadevices/pkg/driver/audiotest"
 	_ "github.com/pion/mediadevices/pkg/driver/videotest"
+	"github.com/pion/mediadevices/pkg/io/audio"
+	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
 )

 func TestGetUserMedia(t *testing.T) {
+	videoParams := mockParams{
+		BaseParams: codec.BaseParams{
+			BitRate: 100000,
+		},
+		name: "MockVideo",
+	}
+	audioParams := mockParams{
+		BaseParams: codec.BaseParams{
+			BitRate: 32000,
+		},
+		name: "MockAudio",
+	}
+	md := NewMediaDevicesFromCodecs(
+		map[webrtc.RTPCodecType][]*webrtc.RTPCodec{
+			webrtc.RTPCodecTypeVideo: {
+				{Type: webrtc.RTPCodecTypeVideo, Name: "MockVideo", PayloadType: 1},
+			},
+			webrtc.RTPCodecTypeAudio: {
+				{Type: webrtc.RTPCodecTypeAudio, Name: "MockAudio", PayloadType: 2},
+			},
+		},
+		WithTrackGenerator(
+			func(_ uint8, _ uint32, id, _ string, codec *webrtc.RTPCodec) (
+				LocalTrack, error,
+			) {
+				return newMockTrack(codec, id), nil
+			},
+		),
+	)
 	constraints := MediaStreamConstraints{
 		Video: func(c *MediaTrackConstraints) {
+			c.Enabled = true
 			c.Width = prop.Int(640)
 			c.Height = prop.Int(480)
+			params := videoParams
+			c.VideoEncoderBuilders = []codec.VideoEncoderBuilder{&params}
 		},
 		Audio: func(c *MediaTrackConstraints) {
+			c.Enabled = true
+			params := audioParams
+			c.AudioEncoderBuilders = []codec.AudioEncoderBuilder{&params}
 		},
 	}
 	constraintsWrong := MediaStreamConstraints{
 		Video: func(c *MediaTrackConstraints) {
-			c.Width = prop.IntExact(10000)
+			c.Enabled = true
+			c.Width = prop.Int(640)
 			c.Height = prop.Int(480)
+			params := videoParams
+			params.BitRate = 0
+			c.VideoEncoderBuilders = []codec.VideoEncoderBuilder{&params}
 		},
 		Audio: func(c *MediaTrackConstraints) {
+			c.Enabled = true
+			params := audioParams
+			c.AudioEncoderBuilders = []codec.AudioEncoderBuilder{&params}
 		},
 	}

 	// GetUserMedia with broken parameters
-	ms, err := GetUserMedia(constraintsWrong)
+	ms, err := md.GetUserMedia(constraintsWrong)
 	if err == nil {
 		t.Fatal("Expected error, but got nil")
 	}

 	// GetUserMedia with correct parameters
-	ms, err = GetUserMedia(constraints)
+	ms, err = md.GetUserMedia(constraints)
 	if err != nil {
 		t.Fatalf("Unexpected error: %v", err)
 	}
@@ -54,11 +103,11 @@ func TestGetUserMedia(t *testing.T) {
 	time.Sleep(50 * time.Millisecond)

 	for _, track := range tracks {
-		track.Close()
+		track.Stop()
 	}

 	// Stop and retry GetUserMedia
-	ms, err = GetUserMedia(constraints)
+	ms, err = md.GetUserMedia(constraints)
 	if err != nil {
 		t.Fatalf("Failed to GetUserMedia after the previsous tracks stopped: %v", err)
 	}
@@ -75,10 +124,104 @@ func TestGetUserMedia(t *testing.T) {
 	}
 	time.Sleep(50 * time.Millisecond)
 	for _, track := range tracks {
-		track.Close()
+		track.Stop()
 	}
 }

+type mockTrack struct {
+	codec *webrtc.RTPCodec
+	id    string
+}
+
+func newMockTrack(codec *webrtc.RTPCodec, id string) *mockTrack {
+	return &mockTrack{
+		codec: codec,
+		id:    id,
+	}
+}
+
+func (t *mockTrack) WriteSample(s media.Sample) error {
+	return nil
+}
+
+func (t *mockTrack) Codec() *webrtc.RTPCodec {
+	return t.codec
+}
+
+func (t *mockTrack) ID() string {
+	return t.id
+}
+
+func (t *mockTrack) Kind() webrtc.RTPCodecType {
+	return t.codec.Type
+}
+
+type mockParams struct {
+	codec.BaseParams
+	name string
+}
+
+func (params *mockParams) Name() string {
+	return params.name
+}
+
+func (params *mockParams) BuildVideoEncoder(r video.Reader, p prop.Media) (codec.ReadCloser, error) {
+	if params.BitRate == 0 {
+		// This is a dummy error to test the failure condition.
+		return nil, errors.New("wrong codec parameter")
+	}
+	return &mockVideoCodec{
+		r:      r,
+		closed: make(chan struct{}),
+	}, nil
+}
+
+func (params *mockParams) BuildAudioEncoder(r audio.Reader, p prop.Media) (codec.ReadCloser, error) {
+	return &mockAudioCodec{
+		r:      r,
+		closed: make(chan struct{}),
+	}, nil
+}
+
+type mockCodec struct{}
+
+func (e *mockCodec) SetBitRate(b int) error {
+	return nil
+}
+
+func (e *mockCodec) ForceKeyFrame() error {
+	return nil
+}
+
+type mockVideoCodec struct {
+	mockCodec
+	r      video.Reader
+	closed chan struct{}
+}
+
+func (m *mockVideoCodec) Read(b []byte) (int, error) {
+	if _, err := m.r.Read(); err != nil {
+		return 0, err
+	}
+	return len(b), nil
+}
+
+func (m *mockVideoCodec) Close() error { return nil }
+
+type mockAudioCodec struct {
+	mockCodec
+	r      audio.Reader
+	closed chan struct{}
+}
+
+func (m *mockAudioCodec) Read(b []byte) (int, error) {
+	if _, err := m.r.Read(); err != nil {
+		return 0, err
+	}
+	return len(b), nil
+}
+func (m *mockAudioCodec) Close() error { return nil }
+
 func TestSelectBestDriverConstraintsResultIsSetProperly(t *testing.T) {
 	filterFn := driver.FilterVideoRecorder()
 	drivers := driver.GetManager().Query(filterFn)
--- a/mediastream.go
+++ b/mediastream.go
@@ -2,85 +2,89 @@ package mediadevices

 import (
 	"sync"
+
+	"github.com/pion/webrtc/v2"
 )

 // MediaStream is an interface that represents a collection of existing tracks.
 type MediaStream interface {
 	// GetAudioTracks implements https://w3c.github.io/mediacapture-main/#dom-mediastream-getaudiotracks
-	GetAudioTracks() []Track
+	GetAudioTracks() []Tracker
 	// GetVideoTracks implements https://w3c.github.io/mediacapture-main/#dom-mediastream-getvideotracks
-	GetVideoTracks() []Track
+	GetVideoTracks() []Tracker
 	// GetTracks implements https://w3c.github.io/mediacapture-main/#dom-mediastream-gettracks
-	GetTracks() []Track
+	GetTracks() []Tracker
 	// AddTrack implements https://w3c.github.io/mediacapture-main/#dom-mediastream-addtrack
-	AddTrack(t Track)
+	AddTrack(t Tracker)
 	// RemoveTrack implements https://w3c.github.io/mediacapture-main/#dom-mediastream-removetrack
-	RemoveTrack(t Track)
+	RemoveTrack(t Tracker)
 }

 type mediaStream struct {
-	tracks map[Track]struct{}
-	l      sync.RWMutex
+	trackers map[string]Tracker
+	l        sync.RWMutex
 }

-const trackTypeDefault MediaDeviceType = 0
+const rtpCodecTypeDefault webrtc.RTPCodecType = 0

 // NewMediaStream creates a MediaStream interface that's defined in
 // https://w3c.github.io/mediacapture-main/#dom-mediastream
-func NewMediaStream(tracks ...Track) (MediaStream, error) {
-	m := mediaStream{tracks: make(map[Track]struct{})}
+func NewMediaStream(trackers ...Tracker) (MediaStream, error) {
+	m := mediaStream{trackers: make(map[string]Tracker)}

-	for _, track := range tracks {
-		if _, ok := m.tracks[track]; !ok {
-			m.tracks[track] = struct{}{}
+	for _, tracker := range trackers {
+		id := tracker.LocalTrack().ID()
+		if _, ok := m.trackers[id]; !ok {
+			m.trackers[id] = tracker
 		}
 	}

 	return &m, nil
 }

-func (m *mediaStream) GetAudioTracks() []Track {
-	return m.queryTracks(AudioInput)
+func (m *mediaStream) GetAudioTracks() []Tracker {
+	return m.queryTracks(webrtc.RTPCodecTypeAudio)
 }

-func (m *mediaStream) GetVideoTracks() []Track {
-	return m.queryTracks(VideoInput)
+func (m *mediaStream) GetVideoTracks() []Tracker {
+	return m.queryTracks(webrtc.RTPCodecTypeVideo)
 }

-func (m *mediaStream) GetTracks() []Track {
-	return m.queryTracks(trackTypeDefault)
+func (m *mediaStream) GetTracks() []Tracker {
+	return m.queryTracks(rtpCodecTypeDefault)
 }

 // queryTracks returns all tracks that are the same kind as t.
 // If t is 0, which is the default, queryTracks will return all the tracks.
-func (m *mediaStream) queryTracks(t MediaDeviceType) []Track {
+func (m *mediaStream) queryTracks(t webrtc.RTPCodecType) []Tracker {
 	m.l.RLock()
 	defer m.l.RUnlock()

-	result := make([]Track, 0)
-	for track := range m.tracks {
-		if track.Kind() == t || t == trackTypeDefault {
-			result = append(result, track)
+	result := make([]Tracker, 0)
+	for _, tracker := range m.trackers {
+		if tracker.LocalTrack().Kind() == t || t == rtpCodecTypeDefault {
+			result = append(result, tracker)
 		}
 	}

 	return result
 }

-func (m *mediaStream) AddTrack(t Track) {
+func (m *mediaStream) AddTrack(t Tracker) {
 	m.l.Lock()
 	defer m.l.Unlock()

-	if _, ok := m.tracks[t]; ok {
+	id := t.LocalTrack().ID()
+	if _, ok := m.trackers[id]; ok {
 		return
 	}

-	m.tracks[t] = struct{}{}
+	m.trackers[id] = t
 }

-func (m *mediaStream) RemoveTrack(t Track) {
+func (m *mediaStream) RemoveTrack(t Tracker) {
 	m.l.Lock()
 	defer m.l.Unlock()

-	delete(m.tracks, t)
+	delete(m.trackers, t.LocalTrack().ID())
 }
--- a/mediastream_test.go
+++ b/mediastream_test.go
@@ -1,97 +0,0 @@
-package mediadevices
-
-import (
-	"io"
-	"testing"
-
-	"github.com/pion/webrtc/v2"
-)
-
-type mockMediaStreamTrack struct {
-	kind MediaDeviceType
-}
-
-func (track *mockMediaStreamTrack) ID() string {
-	return ""
-}
-
-func (track *mockMediaStreamTrack) Close() error {
-	return nil
-}
-
-func (track *mockMediaStreamTrack) Kind() MediaDeviceType {
-	return track.kind
-}
-
-func (track *mockMediaStreamTrack) OnEnded(handler func(error)) {
-}
-
-func (track *mockMediaStreamTrack) Bind(pc *webrtc.PeerConnection) (*webrtc.Track, error) {
-	return nil, nil
-}
-
-func (track *mockMediaStreamTrack) Unbind(pc *webrtc.PeerConnection) error {
-	return nil
-}
-
-func (track *mockMediaStreamTrack) NewRTPReader(codecName string, mtu int) (RTPReadCloser, error) {
-	return nil, nil
-}
-
-func (track *mockMediaStreamTrack) NewEncodedReader(codecName string) (io.ReadCloser, error) {
-	return nil, nil
-}
-
-func TestMediaStreamFilters(t *testing.T) {
-	audioTracks := []Track{
-		&mockMediaStreamTrack{AudioInput},
-		&mockMediaStreamTrack{AudioInput},
-		&mockMediaStreamTrack{AudioInput},
-		&mockMediaStreamTrack{AudioInput},
-		&mockMediaStreamTrack{AudioInput},
-	}
-
-	videoTracks := []Track{
-		&mockMediaStreamTrack{VideoInput},
-		&mockMediaStreamTrack{VideoInput},
-		&mockMediaStreamTrack{VideoInput},
-	}
-
-	tracks := append(audioTracks, videoTracks...)
-	stream, err := NewMediaStream(tracks...)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	expect := func(t *testing.T, actual, expected []Track) {
-		if len(actual) != len(expected) {
-			t.Fatalf("%s: Expected to get %d trackers, but got %d trackers", t.Name(), len(expected), len(actual))
-		}
-
-		for _, a := range actual {
-			found := false
-			for _, e := range expected {
-				if e == a {
-					found = true
-					break
-				}
-			}
-
-			if !found {
-				t.Fatalf("%s: Expected to find %p in the query results", t.Name(), a)
-			}
-		}
-	}
-
-	t.Run("GetAudioTracks", func(t *testing.T) {
-		expect(t, stream.GetAudioTracks(), audioTracks)
-	})
-
-	t.Run("GetVideoTracks", func(t *testing.T) {
-		expect(t, stream.GetVideoTracks(), videoTracks)
-	})
-
-	t.Run("GetTracks", func(t *testing.T) {
-		expect(t, stream.GetTracks(), tracks)
-	})
-}
--- a/mediastreamconstraints.go
+++ b/mediastreamconstraints.go
@@ -1,18 +1,40 @@
 package mediadevices

 import (
+	"github.com/pion/mediadevices/pkg/codec"
+	"github.com/pion/mediadevices/pkg/io/audio"
+	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
 )

 type MediaStreamConstraints struct {
 	Audio MediaOption
 	Video MediaOption
-	Codec *CodecSelector
 }

 // MediaTrackConstraints represents https://w3c.github.io/mediacapture-main/#dom-mediatrackconstraints
 type MediaTrackConstraints struct {
 	prop.MediaConstraints
+	Enabled bool
+	// VideoEncoderBuilders are codec builders that are used for encoding the video
+	// and later being used for sending the appropriate RTP payload type.
+	//
+	// If one encoder builder fails to build the codec, the next builder will be used,
+	// repeating until a codec builds. If no builders build successfully, an error is returned.
+	VideoEncoderBuilders []codec.VideoEncoderBuilder
+	// AudioEncoderBuilders are codec builders that are used for encoding the audio
+	// and later being used for sending the appropriate RTP payload type.
+	//
+	// If one encoder builder fails to build the codec, the next builder will be used,
+	// repeating until a codec builds. If no builders build successfully, an error is returned.
+	AudioEncoderBuilders []codec.AudioEncoderBuilder
+	// VideoTransform will be used to transform the video that's coming from the driver.
+	// So, basically it'll look like following: driver -> VideoTransform -> codec
+	VideoTransform video.TransformFunc
+	// AudioTransform will be used to transform the audio that's coming from the driver.
+	// So, basically it'll look like following: driver -> AudioTransform -> code
+	AudioTransform audio.TransformFunc
+
 	selectedMedia prop.Media
 }

--- a/meta.go
+++ b/meta.go
@@ -1,35 +0,0 @@
-package mediadevices
-
-import (
-	"github.com/pion/mediadevices/pkg/io/audio"
-	"github.com/pion/mediadevices/pkg/io/video"
-	"github.com/pion/mediadevices/pkg/prop"
-)
-
-// detectCurrentVideoProp is a small helper to get current video property
-func detectCurrentVideoProp(broadcaster *video.Broadcaster) (prop.Media, error) {
-	var currentProp prop.Media
-
-	// Since broadcaster has a ring buffer internally, a new reader will either read the last
-	// buffered frame or a new frame from the source. This also implies that no frame will be lost
-	// in any case.
-	metaReader := broadcaster.NewReader(false)
-	metaReader = video.DetectChanges(0, func(p prop.Media) { currentProp = p })(metaReader)
-	_, _, err := metaReader.Read()
-
-	return currentProp, err
-}
-
-// detectCurrentAudioProp is a small helper to get current audio property
-func detectCurrentAudioProp(broadcaster *audio.Broadcaster) (prop.Media, error) {
-	var currentProp prop.Media
-
-	// Since broadcaster has a ring buffer internally, a new reader will either read the last
-	// buffered frame or a new frame from the source. This also implies that no frame will be lost
-	// in any case.
-	metaReader := broadcaster.NewReader(false)
-	metaReader = audio.DetectChanges(0, func(p prop.Media) { currentProp = p })(metaReader)
-	_, _, err := metaReader.Read()
-
-	return currentProp, err
-}
--- a/meta_test.go
+++ b/meta_test.go
@@ -1,98 +0,0 @@
-package mediadevices
-
-import (
-	"image"
-	"testing"
-
-	"github.com/pion/mediadevices/pkg/io/audio"
-	"github.com/pion/mediadevices/pkg/io/video"
-	"github.com/pion/mediadevices/pkg/wave"
-)
-
-func TestDetectCurrentVideoProp(t *testing.T) {
-	resolution := image.Rect(0, 0, 4, 4)
-	first := image.NewRGBA(resolution)
-	first.Pix[0] = 1
-	second := image.NewRGBA(resolution)
-	second.Pix[0] = 2
-
-	isFirst := true
-	source := video.ReaderFunc(func() (image.Image, func(), error) {
-		if isFirst {
-			isFirst = true
-			return first, func() {}, nil
-		} else {
-			return second, func() {}, nil
-		}
-	})
-
-	broadcaster := video.NewBroadcaster(source, nil)
-
-	currentProp, err := detectCurrentVideoProp(broadcaster)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if currentProp.Width != resolution.Dx() {
-		t.Fatalf("Expect the actual width to be %d, but got %d", currentProp.Width, resolution.Dx())
-	}
-
-	if currentProp.Height != resolution.Dy() {
-		t.Fatalf("Expect the actual height to be %d, but got %d", currentProp.Height, resolution.Dy())
-	}
-
-	reader := broadcaster.NewReader(false)
-	img, _, err := reader.Read()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	rgba := img.(*image.RGBA)
-	if rgba.Pix[0] != 1 {
-		t.Fatal("Expect the frame after reading the current prop is not the first frame")
-	}
-}
-
-func TestDetectCurrentAudioProp(t *testing.T) {
-	info := wave.ChunkInfo{
-		Len:          4,
-		Channels:     2,
-		SamplingRate: 48000,
-	}
-	first := wave.NewInt16Interleaved(info)
-	first.Data[0] = 1
-	second := wave.NewInt16Interleaved(info)
-	second.Data[0] = 2
-
-	isFirst := true
-	source := audio.ReaderFunc(func() (wave.Audio, func(), error) {
-		if isFirst {
-			isFirst = true
-			return first, func() {}, nil
-		} else {
-			return second, func() {}, nil
-		}
-	})
-
-	broadcaster := audio.NewBroadcaster(source, nil)
-
-	currentProp, err := detectCurrentAudioProp(broadcaster)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if currentProp.ChannelCount != info.Channels {
-		t.Fatalf("Expect the actual channel count to be %d, but got %d", currentProp.ChannelCount, info.Channels)
-	}
-
-	reader := broadcaster.NewReader(false)
-	chunk, _, err := reader.Read()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	realChunk := chunk.(*wave.Int16Interleaved)
-	if realChunk.Data[0] != 1 {
-		t.Fatal("Expect the chunk after reading the current prop is not the first chunk")
-	}
-}
--- a/pkg/avfoundation/avfoundation_darwin.go
+++ b/pkg/avfoundation/avfoundation_darwin.go
@@ -110,12 +110,12 @@ func (rc *ReadCloser) dataCb(data []byte) {
 // Read reads raw data, the format is determined by the media type and property:
 //   - For video, each call will return a frame.
 //   - For audio, each call will return a chunk which its size configured by Latency
-func (rc *ReadCloser) Read() ([]byte, func(), error) {
+func (rc *ReadCloser) Read() ([]byte, error) {
 	data, ok := <-rc.dataChan
 	if !ok {
-		return nil, func() {}, io.EOF
+		return nil, io.EOF
 	}
-	return data, func() {}, nil
+	return data, nil
 }

 // Close closes the capturing session, and no data will flow anymore
--- a/pkg/codec/codec.go
+++ b/pkg/codec/codec.go
@@ -1,45 +1,21 @@
 package codec

 import (
+	"io"
+
 	"github.com/pion/mediadevices/pkg/io/audio"
 	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
-	"github.com/pion/webrtc/v2"
 )

-// RTPCodec wraps webrtc.RTPCodec. RTPCodec might extend webrtc.RTPCodec in the future.
-type RTPCodec struct {
-	*webrtc.RTPCodec
-}
-
-// NewRTPH264Codec is a helper to create an H264 codec
-func NewRTPH264Codec(clockrate uint32) *RTPCodec {
-	return &RTPCodec{webrtc.NewRTPH264Codec(webrtc.DefaultPayloadTypeH264, clockrate)}
-}
-
-// NewRTPVP8Codec is a helper to create an VP8 codec
-func NewRTPVP8Codec(clockrate uint32) *RTPCodec {
-	return &RTPCodec{webrtc.NewRTPVP8Codec(webrtc.DefaultPayloadTypeVP8, clockrate)}
-}
-
-// NewRTPVP9Codec is a helper to create an VP9 codec
-func NewRTPVP9Codec(clockrate uint32) *RTPCodec {
-	return &RTPCodec{webrtc.NewRTPVP9Codec(webrtc.DefaultPayloadTypeVP9, clockrate)}
-}
-
-// NewRTPOpusCodec is a helper to create an Opus codec
-func NewRTPOpusCodec(clockrate uint32) *RTPCodec {
-	return &RTPCodec{webrtc.NewRTPOpusCodec(webrtc.DefaultPayloadTypeOpus, clockrate)}
-}
-
 // AudioEncoderBuilder is the interface that wraps basic operations that are
 // necessary to build the audio encoder.
 //
 // This interface is for codec implementors to provide codec specific params,
 // but still giving generality for the users.
 type AudioEncoderBuilder interface {
-	// RTPCodec represents the codec metadata
-	RTPCodec() *RTPCodec
+	// Name represents the codec name
+	Name() string
 	// BuildAudioEncoder builds audio encoder by given media params and audio input
 	BuildAudioEncoder(r audio.Reader, p prop.Media) (ReadCloser, error)
 }
@@ -50,16 +26,15 @@ type AudioEncoderBuilder interface {
 // This interface is for codec implementors to provide codec specific params,
 // but still giving generality for the users.
 type VideoEncoderBuilder interface {
-	// RTPCodec represents the codec metadata
-	RTPCodec() *RTPCodec
+	// Name represents the codec name
+	Name() string
 	// BuildVideoEncoder builds video encoder by given media params and video input
 	BuildVideoEncoder(r video.Reader, p prop.Media) (ReadCloser, error)
 }

 // ReadCloser is an io.ReadCloser with methods for rate limiting: SetBitRate and ForceKeyFrame
 type ReadCloser interface {
-	Read() (b []byte, release func(), err error)
-	Close() error
+	io.ReadCloser
 	// SetBitRate sets current target bitrate, lower bitrate means smaller data will be transmitted
 	// but this also means that the quality will also be lower.
 	SetBitRate(int) error
--- a/pkg/codec/mmal/bridge.h
+++ b/pkg/codec/mmal/bridge.h
@@ -1,196 +0,0 @@
-#include <interface/mmal/mmal.h>
-#include <interface/mmal/util/mmal_default_components.h>
-#include <interface/mmal/util/mmal_util_params.h>
-#include <stdbool.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-#define CHK(__status, __msg)                                                                                           \
-  do {                                                                                                                 \
-    status.code = __status;                                                                                            \
-    if (status.code != MMAL_SUCCESS) {                                                                                 \
-      status.msg = __msg;                                                                                              \
-      goto CleanUp;                                                                                                    \
-    }                                                                                                                  \
-  } while (0)
-
-typedef struct Status {
-  MMAL_STATUS_T code;
-  const char *msg;
-} Status;
-
-typedef struct Slice {
-  uint8_t *data;
-  int len;
-} Slice;
-
-typedef struct Params {
-  int width, height;
-  uint32_t bitrate;
-  uint32_t key_frame_interval;
-} Params;
-
-typedef struct Encoder {
-  MMAL_COMPONENT_T *component;
-  MMAL_PORT_T *port_in, *port_out;
-  MMAL_QUEUE_T *queue_out;
-  MMAL_POOL_T *pool_in, *pool_out;
-} Encoder;
-
-Status enc_new(Params, Encoder *);
-Status enc_encode(Encoder *, Slice y, Slice cb, Slice cr, MMAL_BUFFER_HEADER_T **);
-Status enc_close(Encoder *);
-
-static void encoder_in_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer) { mmal_buffer_header_release(buffer); }
-
-static void encoder_out_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer) {
-  MMAL_QUEUE_T *queue = (MMAL_QUEUE_T *)port->userdata;
-  mmal_queue_put(queue, buffer);
-}
-
-Status enc_new(Params params, Encoder *encoder) {
-  Status status = {0};
-  bool created = false;
-
-  memset(encoder, 0, sizeof(Encoder));
-
-  CHK(mmal_component_create(MMAL_COMPONENT_DEFAULT_VIDEO_ENCODER, &encoder->component),
-      "Failed to create video encoder component");
-  created = true;
-
-  encoder->port_in = encoder->component->input[0];
-  encoder->port_in->format->type = MMAL_ES_TYPE_VIDEO;
-  encoder->port_in->format->encoding = MMAL_ENCODING_I420;
-  encoder->port_in->format->es->video.width = params.width;
-  encoder->port_in->format->es->video.height = params.height;
-  encoder->port_in->format->es->video.par.num = 1;
-  encoder->port_in->format->es->video.par.den = 1;
-  encoder->port_in->format->es->video.crop.x = 0;
-  encoder->port_in->format->es->video.crop.y = 0;
-  encoder->port_in->format->es->video.crop.width = params.width;
-  encoder->port_in->format->es->video.crop.height = params.height;
-  CHK(mmal_port_format_commit(encoder->port_in), "Failed to commit input port format");
-
-  encoder->port_out = encoder->component->output[0];
-  encoder->port_out->format->type = MMAL_ES_TYPE_VIDEO;
-  encoder->port_out->format->encoding = MMAL_ENCODING_H264;
-  encoder->port_out->format->bitrate = params.bitrate;
-  CHK(mmal_port_format_commit(encoder->port_out), "Failed to commit output port format");
-
-  MMAL_PARAMETER_VIDEO_PROFILE_T encoder_param_profile = {0};
-  encoder_param_profile.hdr.id = MMAL_PARAMETER_PROFILE;
-  encoder_param_profile.hdr.size = sizeof(encoder_param_profile);
-  encoder_param_profile.profile[0].profile = MMAL_VIDEO_PROFILE_H264_BASELINE;
-  encoder_param_profile.profile[0].level = MMAL_VIDEO_LEVEL_H264_42;
-  CHK(mmal_port_parameter_set(encoder->port_out, &encoder_param_profile.hdr), "Failed to set encoder profile param");
-
-  CHK(mmal_port_parameter_set_uint32(encoder->port_out, MMAL_PARAMETER_INTRAPERIOD, params.key_frame_interval),
-      "Failed to set intra period param");
-
-  MMAL_PARAMETER_VIDEO_RATECONTROL_T encoder_param_rate_control = {0};
-  encoder_param_rate_control.hdr.id = MMAL_PARAMETER_RATECONTROL;
-  encoder_param_rate_control.hdr.size = sizeof(encoder_param_rate_control);
-  encoder_param_rate_control.control = MMAL_VIDEO_RATECONTROL_VARIABLE;
-  CHK(mmal_port_parameter_set(encoder->port_out, &encoder_param_rate_control.hdr), "Failed to set rate control param");
-
-  // Some decoders expect SPS/PPS headers to be added to every frame
-  CHK(mmal_port_parameter_set_boolean(encoder->port_out, MMAL_PARAMETER_VIDEO_ENCODE_INLINE_HEADER, MMAL_TRUE),
-      "Failed to set inline header param");
-
-  CHK(mmal_port_parameter_set_boolean(encoder->port_out, MMAL_PARAMETER_VIDEO_ENCODE_HEADERS_WITH_FRAME, MMAL_TRUE),
-      "Failed to set headers with frame param");
-
-  /* FIXME: Somehow this flag is broken? When this flag is on, the encoder will get stuck.
-  // Since our use case is mainly for real time streaming, the encoder should optimized for low latency
-  CHK(mmal_port_parameter_set_boolean(encoder->port_out, MMAL_PARAMETER_VIDEO_ENCODE_H264_LOW_LATENCY, MMAL_TRUE),
-      "Failed to set low latency param");
-  */
-
-  // Now we know the format of both ports and the requirements of the encoder, we can create
-  // our buffer headers and their associated memory buffers. We use the buffer pool API for this.
-  encoder->port_in->buffer_num = encoder->port_in->buffer_num_min;
-  // mmal calculates recommended size that's big enough to store all of the pixels
-  encoder->port_in->buffer_size = encoder->port_in->buffer_size_recommended;
-  encoder->pool_in = mmal_pool_create(encoder->port_in->buffer_num, encoder->port_in->buffer_size);
-  encoder->port_out->buffer_num = encoder->port_out->buffer_num_min;
-  encoder->port_out->buffer_size = encoder->port_out->buffer_size_recommended;
-  encoder->pool_out = mmal_pool_create(encoder->port_out->buffer_num, encoder->port_out->buffer_size);
-
-  // Create a queue to store our encoded video frames. The callback we will get when
-  // a frame has been encoded will put the frame into this queue.
-  encoder->queue_out = mmal_queue_create();
-  encoder->port_out->userdata = (void *)encoder->queue_out;
-
-  // Enable all the input port and the output port.
-  // The callback specified here is the function which will be called when the buffer header
-  // we sent to the component has been processed.
-  CHK(mmal_port_enable(encoder->port_in, encoder_in_cb), "Failed to enable input port");
-  CHK(mmal_port_enable(encoder->port_out, encoder_out_cb), "Failed to enable output port");
-
-  // Enable the component. Components will only process data when they are enabled.
-  CHK(mmal_component_enable(encoder->component), "Failed to enable component");
-
-CleanUp:
-
-  if (status.code != MMAL_SUCCESS) {
-    if (created) {
-      enc_close(encoder);
-    }
-  }
-
-  return status;
-}
-
-// enc_encode encodes y, cb, cr. The encoded frame is going to be stored in encoded_buffer.
-// IMPORTANT: the caller is responsible to release the ownership of encoded_buffer
-Status enc_encode(Encoder *encoder, Slice y, Slice cb, Slice cr, MMAL_BUFFER_HEADER_T **encoded_buffer) {
-  Status status = {0};
-  MMAL_BUFFER_HEADER_T *buffer;
-  uint32_t required_size;
-
-  // buffer should always be available since the encoding process is blocking
-  buffer = mmal_queue_get(encoder->pool_in->queue);
-  assert(buffer != NULL);
-  // buffer->data should've been allocated with enough memory to contain a frame by pool_in
-  required_size = y.len + cb.len + cr.len;
-  assert(buffer->alloc_size >= required_size);
-  memcpy(buffer->data, y.data, y.len);
-  memcpy(buffer->data + y.len, cb.data, cb.len);
-  memcpy(buffer->data + y.len + cb.len, cr.data, cr.len);
-  buffer->length = required_size;
-  CHK(mmal_port_send_buffer(encoder->port_in, buffer), "Failed to send filled buffer to input port");
-
-  while (1) {
-    // Send empty buffers to the output port to allow the encoder to start
-    // producing frames as soon as it gets input data
-    while ((buffer = mmal_queue_get(encoder->pool_out->queue)) != NULL) {
-      CHK(mmal_port_send_buffer(encoder->port_out, buffer), "Failed to send empty buffers to output port");
-    }
-
-    while ((buffer = mmal_queue_wait(encoder->queue_out)) != NULL) {
-      if ((buffer->flags & MMAL_BUFFER_HEADER_FLAG_FRAME_END) != 0) {
-        *encoded_buffer = buffer;
-        goto CleanUp;
-      }
-
-      mmal_buffer_header_release(buffer);
-    }
-  }
-
-CleanUp:
-
-  return status;
-}
-
-Status enc_close(Encoder *encoder) {
-  Status status = {0};
-
-  mmal_pool_destroy(encoder->pool_out);
-  mmal_pool_destroy(encoder->pool_in);
-  mmal_queue_destroy(encoder->queue_out);
-  mmal_component_destroy(encoder->component);
-
-CleanUp:
-
-  return status;
-}
--- a/pkg/codec/mmal/mmal.go
+++ b/pkg/codec/mmal/mmal.go
@@ -1,113 +0,0 @@
-// Package mmal implements a hardware accelerated H264 encoder for raspberry pi.
-// This package requires libmmal headers and libraries to be built.
-// Reference: https://github.com/raspberrypi/userland/tree/master/interface/mmal
-package mmal
-
-// #cgo CFLAGS: -I/opt/vc/include
-// #cgo LDFLAGS: -L/opt/vc/lib -lmmal -lmmal_core -lmmal_util -lmmal_vc_client -lbcm_host -lvcsm -lvcos
-// #include "bridge.h"
-import "C"
-import (
-	"fmt"
-	"image"
-	"io"
-	"sync"
-	"unsafe"
-
-	"github.com/pion/mediadevices/pkg/codec"
-	"github.com/pion/mediadevices/pkg/io/video"
-	"github.com/pion/mediadevices/pkg/prop"
-)
-
-type encoder struct {
-	engine C.Encoder
-	r      video.Reader
-	mu     sync.Mutex
-	closed bool
-	cntr   int
-}
-
-func statusToErr(status *C.Status) error {
-	return fmt.Errorf("(status = %d) %s", int(status.code), C.GoString(status.msg))
-}
-
-func newEncoder(r video.Reader, p prop.Media, params Params) (codec.ReadCloser, error) {
-	if params.KeyFrameInterval == 0 {
-		params.KeyFrameInterval = 60
-	}
-
-	if params.BitRate == 0 {
-		params.BitRate = 300000
-	}
-
-	e := encoder{
-		r: video.ToI420(r),
-	}
-	status := C.enc_new(C.Params{
-		width:              C.int(p.Width),
-		height:             C.int(p.Height),
-		bitrate:            C.uint(params.BitRate),
-		key_frame_interval: C.uint(params.KeyFrameInterval),
-	}, &e.engine)
-	if status.code != 0 {
-		return nil, statusToErr(&status)
-	}
-
-	return &e, nil
-}
-
-func (e *encoder) Read() ([]byte, func(), error) {
-	e.mu.Lock()
-	defer e.mu.Unlock()
-
-	if e.closed {
-		return nil, func() {}, io.EOF
-	}
-
-	img, _, err := e.r.Read()
-	if err != nil {
-		return nil, func() {}, err
-	}
-	imgReal := img.(*image.YCbCr)
-	var y, cb, cr C.Slice
-	y.data = (*C.uchar)(&imgReal.Y[0])
-	y.len = C.int(len(imgReal.Y))
-	cb.data = (*C.uchar)(&imgReal.Cb[0])
-	cb.len = C.int(len(imgReal.Cb))
-	cr.data = (*C.uchar)(&imgReal.Cr[0])
-	cr.len = C.int(len(imgReal.Cr))
-
-	var encodedBuffer *C.MMAL_BUFFER_HEADER_T
-	status := C.enc_encode(&e.engine, y, cb, cr, &encodedBuffer)
-	if status.code != 0 {
-		return nil, func() {}, statusToErr(&status)
-	}
-
-	// GoBytes copies the C array to Go slice. After this, it's safe to release the C array
-	encoded := C.GoBytes(unsafe.Pointer(encodedBuffer.data), C.int(encodedBuffer.length))
-	// Release the buffer so that mmal can reuse this memory
-	C.mmal_buffer_header_release(encodedBuffer)
-
-	return encoded, func() {}, err
-}
-
-func (e *encoder) SetBitRate(b int) error {
-	panic("SetBitRate is not implemented")
-}
-
-func (e *encoder) ForceKeyFrame() error {
-	panic("ForceKeyFrame is not implemented")
-}
-
-func (e *encoder) Close() error {
-	e.mu.Lock()
-	defer e.mu.Unlock()
-
-	if e.closed {
-		return nil
-	}
-
-	e.closed = true
-	C.enc_close(&e.engine)
-	return nil
-}
--- a/pkg/codec/mmal/params.go
+++ b/pkg/codec/mmal/params.go
@@ -1,31 +0,0 @@
-package mmal
-
-import (
-	"github.com/pion/mediadevices/pkg/codec"
-	"github.com/pion/mediadevices/pkg/io/video"
-	"github.com/pion/mediadevices/pkg/prop"
-)
-
-// Params stores libmmal specific encoding parameters.
-type Params struct {
-	codec.BaseParams
-}
-
-// NewParams returns default mmal codec specific parameters.
-func NewParams() (Params, error) {
-	return Params{
-		BaseParams: codec.BaseParams{
-			KeyFrameInterval: 60,
-		},
-	}, nil
-}
-
-// RTPCodec represents the codec metadata
-func (p *Params) RTPCodec() *codec.RTPCodec {
-	return codec.NewRTPH264Codec(90000)
-}
-
-// BuildVideoEncoder builds mmal encoder with given params
-func (p *Params) BuildVideoEncoder(r video.Reader, property prop.Media) (codec.ReadCloser, error) {
-	return newEncoder(r, property, *p)
-}
--- a/pkg/codec/openh264/openh264.go
+++ b/pkg/codec/openh264/openh264.go
@@ -16,6 +16,7 @@ import (
 	"unsafe"

 	"github.com/pion/mediadevices/pkg/codec"
+	mio "github.com/pion/mediadevices/pkg/io"
 	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
 )
@@ -23,6 +24,7 @@ import (
 type encoder struct {
 	engine *C.Encoder
 	r      video.Reader
+	buff   []byte

 	mu     sync.Mutex
 	closed bool
@@ -50,17 +52,26 @@ func newEncoder(r video.Reader, p prop.Media, params Params) (codec.ReadCloser,
 	}, nil
 }

-func (e *encoder) Read() ([]byte, func(), error) {
+func (e *encoder) Read(p []byte) (n int, err error) {
 	e.mu.Lock()
 	defer e.mu.Unlock()

 	if e.closed {
-		return nil, func() {}, io.EOF
+		return 0, io.EOF
 	}

-	img, _, err := e.r.Read()
+	if e.buff != nil {
+		n, err = mio.Copy(p, e.buff)
+		if err == nil {
+			e.buff = nil
+		}
+
+		return n, err
+	}
+
+	img, err := e.r.Read()
 	if err != nil {
-		return nil, func() {}, err
+		return 0, err
 	}

 	yuvImg := img.(*image.YCbCr)
@@ -74,11 +85,16 @@ func (e *encoder) Read() ([]byte, func(), error) {
 		width:  C.int(bounds.Max.X - bounds.Min.X),
 	}, &rv)
 	if err := errResult(rv); err != nil {
-		return nil, func() {}, fmt.Errorf("failed in encoding: %v", err)
+		return 0, fmt.Errorf("failed in encoding: %v", err)
 	}

 	encoded := C.GoBytes(unsafe.Pointer(s.data), s.data_len)
-	return encoded, func() {}, nil
+	n, err = mio.Copy(p, encoded)
+	if err != nil {
+		e.buff = encoded
+	}
+
+	return n, err
 }

 func (e *encoder) SetBitRate(b int) error {
--- a/pkg/codec/openh264/params.go
+++ b/pkg/codec/openh264/params.go
@@ -4,6 +4,7 @@ import (
 	"github.com/pion/mediadevices/pkg/codec"
 	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
+	"github.com/pion/webrtc/v2"
 )

 // Params stores libopenh264 specific encoding parameters.
@@ -20,9 +21,9 @@ func NewParams() (Params, error) {
 	}, nil
 }

-// RTPCodec represents the codec metadata
-func (p *Params) RTPCodec() *codec.RTPCodec {
-	return codec.NewRTPH264Codec(90000)
+// Name represents the codec name
+func (p *Params) Name() string {
+	return webrtc.H264
 }

 // BuildVideoEncoder builds openh264 encoder with given params
--- a/pkg/codec/opus/opus.go
+++ b/pkg/codec/opus/opus.go
@@ -72,22 +72,27 @@ func newEncoder(r audio.Reader, p prop.Media, params Params) (codec.ReadCloser,
 	return &e, nil
 }

-func (e *encoder) Read() ([]byte, func(), error) {
-	buff, _, err := e.reader.Read()
+func (e *encoder) Read(p []byte) (int, error) {
+	buff, err := e.reader.Read()
 	if err != nil {
-		return nil, func() {}, err
+		return 0, err
 	}

-	encoded := make([]byte, 1024)
 	switch b := buff.(type) {
 	case *wave.Int16Interleaved:
-		n, err := e.engine.Encode(b.Data, encoded)
-		return encoded[:n:n], func() {}, err
+		n, err := e.engine.Encode(b.Data, p)
+		if err != nil {
+			return n, err
+		}
+		return n, nil
 	case *wave.Float32Interleaved:
-		n, err := e.engine.EncodeFloat32(b.Data, encoded)
-		return encoded[:n:n], func() {}, err
+		n, err := e.engine.EncodeFloat32(b.Data, p)
+		if err != nil {
+			return n, err
+		}
+		return n, nil
 	default:
-		return nil, func() {}, errors.New("unknown type of audio buffer")
+		return 0, errors.New("unknown type of audio buffer")
 	}
 }

--- a/pkg/codec/opus/params.go
+++ b/pkg/codec/opus/params.go
@@ -5,6 +5,7 @@ import (
 	"github.com/pion/mediadevices/pkg/io/audio"
 	"github.com/pion/mediadevices/pkg/prop"
 	"github.com/pion/mediadevices/pkg/wave/mixer"
+	"github.com/pion/webrtc/v2"
 )

 // Params stores opus specific encoding parameters.
@@ -19,9 +20,9 @@ func NewParams() (Params, error) {
 	return Params{}, nil
 }

-// RTPCodec represents the codec metadata
-func (p *Params) RTPCodec() *codec.RTPCodec {
-	return codec.NewRTPOpusCodec(48000)
+// Name represents the codec name
+func (p *Params) Name() string {
+	return webrtc.Opus
 }

 // BuildAudioEncoder builds opus encoder with given params
--- a/pkg/codec/vaapi/params.go
+++ b/pkg/codec/vaapi/params.go
@@ -4,6 +4,7 @@ import (
 	"github.com/pion/mediadevices/pkg/codec"
 	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
+	"github.com/pion/webrtc/v2"
 )

 // ParamsVP8 stores VP8 encoding parameters.
@@ -43,9 +44,9 @@ func NewVP8Params() (ParamsVP8, error) {
 	}, nil
 }

-// RTPCodec represents the codec metadata
-func (p *ParamsVP8) RTPCodec() *codec.RTPCodec {
-	return codec.NewRTPVP8Codec(90000)
+// Name represents the codec name
+func (p *ParamsVP8) Name() string {
+	return webrtc.VP8
 }

 // BuildVideoEncoder builds VP8 encoder with given params
@@ -112,9 +113,9 @@ func NewVP9Params() (ParamsVP9, error) {
 	}, nil
 }

-// RTPCodec represents the codec metadata
-func (p *ParamsVP9) RTPCodec() *codec.RTPCodec {
-	return codec.NewRTPVP9Codec(90000)
+// Name represents the codec name
+func (p *ParamsVP9) Name() string {
+	return webrtc.VP9
 }

 // BuildVideoEncoder builds VP9 encoder with given params
--- a/pkg/codec/vaapi/vp8.go
+++ b/pkg/codec/vaapi/vp8.go
@@ -64,6 +64,7 @@ import (
 	"unsafe"

 	"github.com/pion/mediadevices/pkg/codec"
+	mio "github.com/pion/mediadevices/pkg/io"
 	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
 )
@@ -79,6 +80,7 @@ const (

 type encoderVP8 struct {
 	r     video.Reader
+	buf   []byte
 	frame []byte

 	fdDRI    C.int
@@ -295,17 +297,25 @@ func newVP8Encoder(r video.Reader, p prop.Media, params ParamsVP8) (codec.ReadCl
 	return e, nil
 }

-func (e *encoderVP8) Read() ([]byte, func(), error) {
+func (e *encoderVP8) Read(p []byte) (int, error) {
 	e.mu.Lock()
 	defer e.mu.Unlock()

 	if e.closed {
-		return nil, func() {}, io.EOF
+		return 0, io.EOF
 	}

-	img, _, err := e.r.Read()
+	if e.buf != nil {
+		n, err := mio.Copy(p, e.buf)
+		if err == nil {
+			e.buf = nil
+		}
+		return n, err
+	}
+
+	img, err := e.r.Read()
 	if err != nil {
-		return nil, func() {}, err
+		return 0, err
 	}
 	yuvImg := img.(*image.YCbCr)

@@ -347,7 +357,7 @@ func (e *encoderVP8) Read() ([]byte, func(), error) {
 			}
 		}
 		if e.picParam.reconstructed_frame == C.VA_INVALID_SURFACE {
-			return nil, func() {}, errors.New("no available surface")
+			return 0, errors.New("no available surface")
 		}

 		C.setForceKFFlagVP8(&e.picParam, 0)
@@ -415,7 +425,7 @@ func (e *encoderVP8) Read() ([]byte, func(), error) {
 			C.size_t(uintptr(p.src)),
 			&id,
 		); s != C.VA_STATUS_SUCCESS {
-			return nil, func() {}, fmt.Errorf("failed to create buffer: %s", C.GoString(C.vaErrorStr(s)))
+			return 0, fmt.Errorf("failed to create buffer: %s", C.GoString(C.vaErrorStr(s)))
 		}
 		buffs = append(buffs, id)
 	}
@@ -425,17 +435,17 @@ func (e *encoderVP8) Read() ([]byte, func(), error) {
 		e.display, e.ctxID,
 		e.surfs[surfaceVP8Input],
 	); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to begin picture: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to begin picture: %s", C.GoString(C.vaErrorStr(s)))
 	}

 	// Upload image
 	var vaImg C.VAImage
 	var rawBuf unsafe.Pointer
 	if s := C.vaDeriveImage(e.display, e.surfs[surfaceVP8Input], &vaImg); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to derive image: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to derive image: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	if s := C.vaMapBuffer(e.display, vaImg.buf, &rawBuf); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to map buffer: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to map buffer: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	// TODO: use vaImg.pitches to support padding
 	C.memcpy(
@@ -451,10 +461,10 @@ func (e *encoderVP8) Read() ([]byte, func(), error) {
 		unsafe.Pointer(&yuvImg.Cr[0]), C.size_t(len(yuvImg.Cr)),
 	)
 	if s := C.vaUnmapBuffer(e.display, vaImg.buf); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to unmap buffer: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to unmap buffer: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	if s := C.vaDestroyImage(e.display, vaImg.image_id); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to destroy image: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to destroy image: %s", C.GoString(C.vaErrorStr(s)))
 	}

 	if s := C.vaRenderPicture(
@@ -462,38 +472,38 @@ func (e *encoderVP8) Read() ([]byte, func(), error) {
 		&buffs[1], // 0 is for ouput
 		C.int(len(buffs)-1),
 	); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to render picture: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to render picture: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	if s := C.vaEndPicture(
 		e.display, e.ctxID,
 	); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to end picture: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to end picture: %s", C.GoString(C.vaErrorStr(s)))
 	}

 	// Load encoded data
 	for retry := 3; retry >= 0; retry-- {
 		if s := C.vaSyncSurface(e.display, e.picParam.reconstructed_frame); s != C.VA_STATUS_SUCCESS {
-			return nil, func() {}, fmt.Errorf("failed to sync surface: %s", C.GoString(C.vaErrorStr(s)))
+			return 0, fmt.Errorf("failed to sync surface: %s", C.GoString(C.vaErrorStr(s)))
 		}
 		var surfStat C.VASurfaceStatus
 		if s := C.vaQuerySurfaceStatus(
 			e.display, e.picParam.reconstructed_frame, &surfStat,
 		); s != C.VA_STATUS_SUCCESS {
-			return nil, func() {}, fmt.Errorf("failed to query surface status: %s", C.GoString(C.vaErrorStr(s)))
+			return 0, fmt.Errorf("failed to query surface status: %s", C.GoString(C.vaErrorStr(s)))
 		}
 		if surfStat == C.VASurfaceReady {
 			break
 		}
 		if retry == 0 {
-			return nil, func() {}, fmt.Errorf("failed to sync surface: %d", surfStat)
+			return 0, fmt.Errorf("failed to sync surface: %d", surfStat)
 		}
 	}
 	var seg *C.VACodedBufferSegment
 	if s := C.vaMapBufferSeg(e.display, buffs[0], &seg); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to map buffer: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to map buffer: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	if seg.status&C.VA_CODED_BUF_STATUS_SLICE_OVERFLOW_MASK != 0 {
-		return nil, func() {}, errors.New("buffer size too small")
+		return 0, errors.New("buffer size too small")
 	}

 	if cap(e.frame) < int(seg.size) {
@@ -506,13 +516,13 @@ func (e *encoderVP8) Read() ([]byte, func(), error) {
 	)

 	if s := C.vaUnmapBuffer(e.display, buffs[0]); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to unmap buffer: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to unmap buffer: %s", C.GoString(C.vaErrorStr(s)))
 	}

 	// Destroy buffers
 	for _, b := range buffs {
 		if s := C.vaDestroyBuffer(e.display, b); s != C.VA_STATUS_SUCCESS {
-			return nil, func() {}, fmt.Errorf("failed to destroy buffer: %s", C.GoString(C.vaErrorStr(s)))
+			return 0, fmt.Errorf("failed to destroy buffer: %s", C.GoString(C.vaErrorStr(s)))
 		}
 	}

@@ -535,9 +545,11 @@ func (e *encoderVP8) Read() ([]byte, func(), error) {
 	e.picParam.ref_last_frame = e.picParam.reconstructed_frame
 	C.setRefreshLastFlagVP8(&e.picParam, 1)

-	encoded := make([]byte, len(e.frame))
-	copy(encoded, e.frame)
-	return encoded, func() {}, err
+	n, err := mio.Copy(p, e.frame)
+	if err != nil {
+		e.buf = e.frame
+	}
+	return n, err
 }

 func (e *encoderVP8) SetBitRate(b int) error {
--- a/pkg/codec/vaapi/vp9.go
+++ b/pkg/codec/vaapi/vp9.go
@@ -47,6 +47,7 @@ import (
 	"unsafe"

 	"github.com/pion/mediadevices/pkg/codec"
+	mio "github.com/pion/mediadevices/pkg/io"
 	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
 )
@@ -66,6 +67,7 @@ const (

 type encoderVP9 struct {
 	r     video.Reader
+	buf   []byte
 	frame []byte

 	fdDRI    C.int
@@ -284,17 +286,25 @@ func newVP9Encoder(r video.Reader, p prop.Media, params ParamsVP9) (codec.ReadCl
 	return e, nil
 }

-func (e *encoderVP9) Read() ([]byte, func(), error) {
+func (e *encoderVP9) Read(p []byte) (int, error) {
 	e.mu.Lock()
 	defer e.mu.Unlock()

 	if e.closed {
-		return nil, func() {}, io.EOF
+		return 0, io.EOF
 	}

-	img, _, err := e.r.Read()
+	if e.buf != nil {
+		n, err := mio.Copy(p, e.buf)
+		if err == nil {
+			e.buf = nil
+		}
+		return n, err
+	}
+
+	img, err := e.r.Read()
 	if err != nil {
-		return nil, func() {}, err
+		return 0, err
 	}
 	yuvImg := img.(*image.YCbCr)

@@ -378,7 +388,7 @@ func (e *encoderVP9) Read() ([]byte, func(), error) {
 			C.size_t(uintptr(p.src)),
 			&id,
 		); s != C.VA_STATUS_SUCCESS {
-			return nil, func() {}, fmt.Errorf("failed to create buffer: %s", C.GoString(C.vaErrorStr(s)))
+			return 0, fmt.Errorf("failed to create buffer: %s", C.GoString(C.vaErrorStr(s)))
 		}
 		buffs = append(buffs, id)
 	}
@@ -388,17 +398,17 @@ func (e *encoderVP9) Read() ([]byte, func(), error) {
 		e.display, e.ctxID,
 		e.surfs[surfaceVP9Input],
 	); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to begin picture: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to begin picture: %s", C.GoString(C.vaErrorStr(s)))
 	}

 	// Upload image
 	var vaImg C.VAImage
 	var rawBuf unsafe.Pointer
 	if s := C.vaDeriveImage(e.display, e.surfs[surfaceVP9Input], &vaImg); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to derive image: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to derive image: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	if s := C.vaMapBuffer(e.display, vaImg.buf, &rawBuf); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to map buffer: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to map buffer: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	// TODO: use vaImg.pitches to support padding
 	C.copyI420toNV12(
@@ -409,10 +419,10 @@ func (e *encoderVP9) Read() ([]byte, func(), error) {
 		C.uint(len(yuvImg.Y)),
 	)
 	if s := C.vaUnmapBuffer(e.display, vaImg.buf); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to unmap buffer: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to unmap buffer: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	if s := C.vaDestroyImage(e.display, vaImg.image_id); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to destroy image: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to destroy image: %s", C.GoString(C.vaErrorStr(s)))
 	}

 	if s := C.vaRenderPicture(
@@ -420,27 +430,27 @@ func (e *encoderVP9) Read() ([]byte, func(), error) {
 		&buffs[1], // 0 is for ouput
 		C.int(len(buffs)-1),
 	); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to render picture: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to render picture: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	if s := C.vaEndPicture(
 		e.display, e.ctxID,
 	); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to end picture: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to end picture: %s", C.GoString(C.vaErrorStr(s)))
 	}

 	// Load encoded data
 	if s := C.vaSyncSurface(e.display, e.picParam.reconstructed_frame); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to sync surface: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to sync surface: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	var surfStat C.VASurfaceStatus
 	if s := C.vaQuerySurfaceStatus(
 		e.display, e.picParam.reconstructed_frame, &surfStat,
 	); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to query surface status: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to query surface status: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	var seg *C.VACodedBufferSegment
 	if s := C.vaMapBufferSeg(e.display, buffs[0], &seg); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to map buffer: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to map buffer: %s", C.GoString(C.vaErrorStr(s)))
 	}
 	if cap(e.frame) < int(seg.size) {
 		e.frame = make([]byte, int(seg.size))
@@ -452,13 +462,13 @@ func (e *encoderVP9) Read() ([]byte, func(), error) {
 	)

 	if s := C.vaUnmapBuffer(e.display, buffs[0]); s != C.VA_STATUS_SUCCESS {
-		return nil, func() {}, fmt.Errorf("failed to unmap buffer: %s", C.GoString(C.vaErrorStr(s)))
+		return 0, fmt.Errorf("failed to unmap buffer: %s", C.GoString(C.vaErrorStr(s)))
 	}

 	// Destroy buffers
 	for _, b := range buffs {
 		if s := C.vaDestroyBuffer(e.display, b); s != C.VA_STATUS_SUCCESS {
-			return nil, func() {}, fmt.Errorf("failed to destroy buffer: %s", C.GoString(C.vaErrorStr(s)))
+			return 0, fmt.Errorf("failed to destroy buffer: %s", C.GoString(C.vaErrorStr(s)))
 		}
 	}

@@ -470,9 +480,11 @@ func (e *encoderVP9) Read() ([]byte, func(), error) {
 		e.slotCurr = 0
 	}

-	encoded := make([]byte, len(e.frame))
-	copy(encoded, e.frame)
-	return encoded, func() {}, err
+	n, err := mio.Copy(p, e.frame)
+	if err != nil {
+		e.buf = e.frame
+	}
+	return n, err
 }

 func (e *encoderVP9) SetBitRate(b int) error {
--- a/pkg/codec/vpx/vpx.go
+++ b/pkg/codec/vpx/vpx.go
@@ -56,8 +56,10 @@ import (
 	"unsafe"

 	"github.com/pion/mediadevices/pkg/codec"
+	mio "github.com/pion/mediadevices/pkg/io"
 	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
+	"github.com/pion/webrtc/v2"
 )

 type encoder struct {
@@ -66,6 +68,7 @@ type encoder struct {
 	cfg        *C.vpx_codec_enc_cfg_t
 	r          video.Reader
 	frameIndex int
+	buff       []byte
 	tStart     int
 	tLastFrame int
 	frame      []byte
@@ -92,9 +95,9 @@ func NewVP8Params() (VP8Params, error) {
 	}, nil
 }

-// RTPCodec represents the codec metadata
-func (p *VP8Params) RTPCodec() *codec.RTPCodec {
-	return codec.NewRTPVP8Codec(90000)
+// Name represents the codec name
+func (p *VP8Params) Name() string {
+	return webrtc.VP8
 }

 // BuildVideoEncoder builds VP8 encoder with given params
@@ -119,9 +122,9 @@ func NewVP9Params() (VP9Params, error) {
 	}, nil
 }

-// RTPCodec represents the codec metadata
-func (p *VP9Params) RTPCodec() *codec.RTPCodec {
-	return codec.NewRTPVP9Codec(90000)
+// Name represents the codec name
+func (p *VP9Params) Name() string {
+	return webrtc.VP9
 }

 // BuildVideoEncoder builds VP9 encoder with given params
@@ -204,17 +207,25 @@ func newEncoder(r video.Reader, p prop.Media, params Params, codecIface *C.vpx_c
 	}, nil
 }

-func (e *encoder) Read() ([]byte, func(), error) {
+func (e *encoder) Read(p []byte) (int, error) {
 	e.mu.Lock()
 	defer e.mu.Unlock()

 	if e.closed {
-		return nil, func() {}, io.EOF
+		return 0, io.EOF
 	}

-	img, _, err := e.r.Read()
+	if e.buff != nil {
+		n, err := mio.Copy(p, e.buff)
+		if err == nil {
+			e.buff = nil
+		}
+		return n, err
+	}
+
+	img, err := e.r.Read()
 	if err != nil {
-		return nil, func() {}, err
+		return 0, err
 	}
 	yuvImg := img.(*image.YCbCr)
 	bounds := yuvImg.Bounds()
@@ -230,29 +241,20 @@ func (e *encoder) Read() ([]byte, func(), error) {
 	if e.cfg.g_w != C.uint(width) || e.cfg.g_h != C.uint(height) {
 		e.cfg.g_w, e.cfg.g_h = C.uint(width), C.uint(height)
 		if ec := C.vpx_codec_enc_config_set(e.codec, e.cfg); ec != C.VPX_CODEC_OK {
-			return nil, func() {}, fmt.Errorf("vpx_codec_enc_config_set failed (%d)", ec)
+			return 0, fmt.Errorf("vpx_codec_enc_config_set failed (%d)", ec)
 		}
 		e.raw.w, e.raw.h = C.uint(width), C.uint(height)
 		e.raw.r_w, e.raw.r_h = C.uint(width), C.uint(height)
 		e.raw.d_w, e.raw.d_h = C.uint(width), C.uint(height)
 	}

-	duration := t - e.tLastFrame
-	// VPX doesn't allow 0 duration. If 0 is given, vpx_codec_encode will fail with VPX_CODEC_INVALID_PARAM.
-	// 0 duration is possible because mediadevices first gets the frame meta data by reading from the source,
-	// and consequently the codec will read the first frame from the buffer. This means the first frame won't
-	// have a pause to the second frame, which means if the delay is <1 ms (vpx duration resolution), duration
-	// is going to be 0.
-	if duration == 0 {
-		duration = 1
-	}
 	var flags int
 	if ec := C.encode_wrapper(
 		e.codec, e.raw,
-		C.long(t-e.tStart), C.ulong(duration), C.long(flags), C.ulong(e.deadline),
+		C.long(t-e.tStart), C.ulong(t-e.tLastFrame), C.long(flags), C.ulong(e.deadline),
 		(*C.uchar)(&yuvImg.Y[0]), (*C.uchar)(&yuvImg.Cb[0]), (*C.uchar)(&yuvImg.Cr[0]),
 	); ec != C.VPX_CODEC_OK {
-		return nil, func() {}, fmt.Errorf("vpx_codec_encode failed (%d)", ec)
+		return 0, fmt.Errorf("vpx_codec_encode failed (%d)", ec)
 	}

 	e.frameIndex++
@@ -270,10 +272,11 @@ func (e *encoder) Read() ([]byte, func(), error) {
 			e.frame = append(e.frame, encoded...)
 		}
 	}
-
-	encoded := make([]byte, len(e.frame))
-	copy(encoded, e.frame)
-	return encoded, func() {}, err
+	n, err := mio.Copy(p, e.frame)
+	if err != nil {
+		e.buff = e.frame
+	}
+	return n, err
 }

 func (e *encoder) SetBitRate(b int) error {
--- a/pkg/codec/x264/bridge.h
+++ b/pkg/codec/x264/bridge.h
@@ -16,7 +16,7 @@ typedef struct Slice {

 typedef struct Encoder {
  x264_t *h;
-  x264_picture_t pic_in;
+  x264_picture_t pic_in, pic_out;
  x264_param_t param;
 } Encoder;

@@ -47,26 +47,20 @@ Encoder *enc_new(x264_param_t param, char *preset, int *rc) {
  e->param.b_repeat_headers = 1;
  e->param.b_annexb = 1;

-  if (x264_param_apply_profile(&e->param, "high") < 0) {
+  if (x264_param_apply_profile(&e->param, "baseline") < 0) {
    *rc = ERR_APPLY_PROFILE;
    goto fail;
  }

-  x264_picture_t pic_in;
-  if (x264_picture_alloc(&pic_in, param.i_csp, param.i_width, param.i_height) < 0) {
+  if (x264_picture_alloc(&e->pic_in, param.i_csp, param.i_width, param.i_height) < 0) {
    *rc = ERR_ALLOC_PICTURE;
    goto fail;
  }

-  // FIXME: we use x264_picture_alloc to set the metadata only, we don't need the allocated memory
-  //        to store the frame. Since we free the frame memory here, we don't need to call
-  //        x264_picture_clean later.
-  e->pic_in = pic_in;
-  x264_picture_clean(&pic_in);
-
  e->h = x264_encoder_open(&e->param);
  if (!e->h) {
    *rc = ERR_OPEN_ENGINE;
+    x264_picture_clean(&e->pic_in);
    goto fail;
  }

@@ -81,24 +75,24 @@ Slice enc_encode(Encoder *e, uint8_t *y, uint8_t *cb, uint8_t *cr, int *rc) {
  x264_nal_t *nal;
  int i_nal;

-  x264_picture_t pic_out;
  e->pic_in.img.plane[0] = y;
  e->pic_in.img.plane[1] = cb;
  e->pic_in.img.plane[2] = cr;

-  int frame_size = x264_encoder_encode(e->h, &nal, &i_nal, &e->pic_in, &pic_out);
+  int frame_size = x264_encoder_encode(e->h, &nal, &i_nal, &e->pic_in, &e->pic_out);
  Slice s = {.data_len = frame_size};
  if (frame_size <= 0) {
    *rc = ERR_ENCODE;
    return s;
  }

-  // e->pic_in.i_pts++;
+  e->pic_in.i_pts++;
  s.data = nal->p_payload;
  return s;
 }

 void enc_close(Encoder *e, int *rc) {
  x264_encoder_close(e->h);
+  x264_picture_clean(&e->pic_in);
  free(e);
-}
+}
--- a/pkg/codec/x264/params.go
+++ b/pkg/codec/x264/params.go
@@ -4,6 +4,7 @@ import (
 	"github.com/pion/mediadevices/pkg/codec"
 	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
+	"github.com/pion/webrtc/v2"
 )

 // Params stores libx264 specific encoding parameters.
@@ -39,9 +40,9 @@ func NewParams() (Params, error) {
 	}, nil
 }

-// RTPCodec represents the codec metadata
-func (p *Params) RTPCodec() *codec.RTPCodec {
-	return codec.NewRTPH264Codec(90000)
+// Name represents the codec name
+func (p *Params) Name() string {
+	return webrtc.H264
 }

 // BuildVideoEncoder builds x264 encoder with given params
--- a/pkg/codec/x264/x264.go
+++ b/pkg/codec/x264/x264.go
@@ -14,12 +14,14 @@ import (
 	"unsafe"

 	"github.com/pion/mediadevices/pkg/codec"
+	mio "github.com/pion/mediadevices/pkg/io"
 	"github.com/pion/mediadevices/pkg/io/video"
 	"github.com/pion/mediadevices/pkg/prop"
 )

 type encoder struct {
 	engine *C.Encoder
+	buff   []byte
 	r      video.Reader
 	mu     sync.Mutex
 	closed bool
@@ -94,17 +96,25 @@ func newEncoder(r video.Reader, p prop.Media, params Params) (codec.ReadCloser,
 	return &e, nil
 }

-func (e *encoder) Read() ([]byte, func(), error) {
+func (e *encoder) Read(p []byte) (int, error) {
 	e.mu.Lock()
 	defer e.mu.Unlock()

 	if e.closed {
-		return nil, func() {}, io.EOF
+		return 0, io.EOF
 	}

-	img, _, err := e.r.Read()
+	if e.buff != nil {
+		n, err := mio.Copy(p, e.buff)
+		if err == nil {
+			e.buff = nil
+		}
+		return n, err
+	}
+
+	img, err := e.r.Read()
 	if err != nil {
-		return nil, func() {}, err
+		return 0, err
 	}
 	yuvImg := img.(*image.YCbCr)

@@ -117,11 +127,15 @@ func (e *encoder) Read() ([]byte, func(), error) {
 		&rc,
 	)
 	if err := errFromC(rc); err != nil {
-		return nil, func() {}, err
+		return 0, err
 	}

 	encoded := C.GoBytes(unsafe.Pointer(s.data), s.data_len)
-	return encoded, func() {}, err
+	n, err := mio.Copy(p, encoded)
+	if err != nil {
+		e.buff = encoded
+	}
+	return n, err
 }

 func (e *encoder) SetBitRate(b int) error {
--- a/pkg/driver/audiotest/dummy.go
+++ b/pkg/driver/audiotest/dummy.go
@@ -52,10 +52,10 @@ func (d *dummy) AudioRecord(p prop.Media) (audio.Reader, error) {

 	closed := d.closed

-	reader := audio.ReaderFunc(func() (wave.Audio, func(), error) {
+	reader := audio.ReaderFunc(func() (wave.Audio, error) {
 		select {
 		case <-closed:
-			return nil, func() {}, io.EOF
+			return nil, io.EOF
 		default:
 		}

@@ -78,7 +78,7 @@ func (d *dummy) AudioRecord(p prop.Media) (audio.Reader, error) {
 				a.SetFloat32(i, ch, wave.Float32Sample(sin[phase]))
 			}
 		}
-		return a, func() {}, nil
+		return a, nil
 	})
 	return reader, nil
 }
--- a/pkg/driver/camera/camera_darwin.go
+++ b/pkg/driver/camera/camera_darwin.go
@@ -56,10 +56,10 @@ func (cam *camera) VideoRecord(property prop.Media) (video.Reader, error) {
 	if err != nil {
 		return nil, err
 	}
-	r := video.ReaderFunc(func() (image.Image, func(), error) {
-		frame, _, err := rc.Read()
+	r := video.ReaderFunc(func() (image.Image, error) {
+		frame, err := rc.Read()
 		if err != nil {
-			return nil, func() {}, err
+			return nil, err
 		}
 		return decoder.Decode(frame, property.Width, property.Height)
 	})
--- a/pkg/driver/camera/camera_linux.go
+++ b/pkg/driver/camera/camera_linux.go
@@ -8,8 +8,7 @@ import (
 	"errors"
 	"image"
 	"io"
-	"os"
-	"path/filepath"
+	"io/ioutil"
 	"sync"

 	"github.com/blackjack/webcam"
@@ -21,42 +20,11 @@ import (

 const (
 	maxEmptyFrameCount = 5
-	prioritizedDevice  = "video0"
 )

 var (
 	errReadTimeout = errors.New("read timeout")
 	errEmptyFrame  = errors.New("empty frame")
-	// Reference: https://commons.wikimedia.org/wiki/File:Vector_Video_Standards2.svg
-	supportedResolutions = [][2]int{
-		{320, 240},
-		{640, 480},
-		{768, 576},
-		{800, 600},
-		{1024, 768},
-		{1280, 854},
-		{1280, 960},
-		{1280, 1024},
-		{1400, 1050},
-		{1600, 1200},
-		{2048, 1536},
-		{320, 200},
-		{800, 480},
-		{854, 480},
-		{1024, 600},
-		{1152, 768},
-		{1280, 720},
-		{1280, 768},
-		{1366, 768},
-		{1280, 800},
-		{1440, 900},
-		{1440, 960},
-		{1680, 1050},
-		{1920, 1080},
-		{2048, 1080},
-		{1920, 1200},
-		{2560, 1600},
-	}
 )

 // Camera implementation using v4l2
@@ -72,43 +40,19 @@ type camera struct {
 }

 func init() {
-	discovered := make(map[string]struct{})
-
-	discover := func(pattern string) {
-		devices, err := filepath.Glob(pattern)
-		if err != nil {
-			// No v4l device.
-			return
-		}
-		for _, device := range devices {
-			label := filepath.Base(device)
-			reallink, err := os.Readlink(device)
-			if err != nil {
-				reallink = label
-			} else {
-				reallink = filepath.Base(reallink)
-			}
-
-			if _, ok := discovered[reallink]; ok {
-				continue
-			}
-
-			discovered[reallink] = struct{}{}
-			cam := newCamera(device)
-			priority := driver.PriorityNormal
-			if label == prioritizedDevice {
-				priority = driver.PriorityHigh
-			}
-			driver.GetManager().Register(cam, driver.Info{
-				Label:      label,
-				DeviceType: driver.Camera,
-				Priority:   priority,
-			})
-		}
+	searchPath := "/dev/v4l/by-path/"
+	devices, err := ioutil.ReadDir(searchPath)
+	if err != nil {
+		// No v4l device.
+		return
+	}
+	for _, device := range devices {
+		cam := newCamera(searchPath + device.Name())
+		driver.GetManager().Register(cam, driver.Info{
+			Label:      device.Name(),
+			DeviceType: driver.Camera,
+		})
 	}
-
-	discover("/dev/v4l/by-path/*")
-	discover("/dev/video*")
 }

 func newCamera(path string) *camera {
@@ -139,8 +83,6 @@ func (c *camera) Open() error {
 		return err
 	}

-	// Late frames should be discarded. Buffering should be handled in higher level.
-	cam.SetBufferCount(1)
 	c.cam = cam
 	return nil
 }
@@ -188,7 +130,7 @@ func (c *camera) VideoRecord(p prop.Media) (video.Reader, error) {
 	ctx, cancel := context.WithCancel(context.Background())
 	c.cancel = cancel
 	var buf []byte
-	r := video.ReaderFunc(func() (img image.Image, release func(), err error) {
+	r := video.ReaderFunc(func() (img image.Image, err error) {
 		// Lock to avoid accessing the buffer after StopStreaming()
 		c.mutex.Lock()
 		defer c.mutex.Unlock()
@@ -197,23 +139,23 @@ func (c *camera) VideoRecord(p prop.Media) (video.Reader, error) {
 		for i := 0; i < maxEmptyFrameCount; i++ {
 			if ctx.Err() != nil {
 				// Return EOF if the camera is already closed.
-				return nil, func() {}, io.EOF
+				return nil, io.EOF
 			}

 			err := cam.WaitForFrame(5) // 5 seconds
 			switch err.(type) {
 			case nil:
 			case *webcam.Timeout:
-				return nil, func() {}, errReadTimeout
+				return nil, errReadTimeout
 			default:
 				// Camera has been stopped.
-				return nil, func() {}, err
+				return nil, err
 			}

 			b, err := cam.ReadFrame()
 			if err != nil {
 				// Camera has been stopped.
-				return nil, func() {}, err
+				return nil, err
 			}

 			// Frame is empty.
@@ -233,7 +175,7 @@ func (c *camera) VideoRecord(p prop.Media) (video.Reader, error) {
 			n := copy(buf, b)
 			return decoder.Decode(buf[:n], p.Width, p.Height)
 		}
-		return nil, func() {}, errEmptyFrame
+		return nil, errEmptyFrame
 	})

 	return r, nil
@@ -243,46 +185,13 @@ func (c *camera) Properties() []prop.Media {
 	properties := make([]prop.Media, 0)
 	for format := range c.cam.GetSupportedFormats() {
 		for _, frameSize := range c.cam.GetSupportedFrameSizes(format) {
-			supportedFormat, ok := c.formats[format]
-			if !ok {
-				continue
-			}
-
-			if frameSize.StepWidth == 0 || frameSize.StepHeight == 0 {
-				properties = append(properties, prop.Media{
-					Video: prop.Video{
-						Width:       int(frameSize.MaxWidth),
-						Height:      int(frameSize.MaxHeight),
-						FrameFormat: supportedFormat,
-					},
-				})
-			} else {
-				// FIXME: we should probably use a custom data structure to capture all of the supported resolutions
-				for _, supportedResolution := range supportedResolutions {
-					minWidth, minHeight := int(frameSize.MinWidth), int(frameSize.MinHeight)
-					maxWidth, maxHeight := int(frameSize.MaxWidth), int(frameSize.MaxHeight)
-					stepWidth, stepHeight := int(frameSize.StepWidth), int(frameSize.StepHeight)
-					width, height := supportedResolution[0], supportedResolution[1]
-
-					if width < minWidth || width > maxWidth ||
-						height < minHeight || height > maxHeight {
-						continue
-					}
-
-					if (width-minWidth)%stepWidth != 0 ||
-						(height-minHeight)%stepHeight != 0 {
-						continue
-					}
-
-					properties = append(properties, prop.Media{
-						Video: prop.Video{
-							Width:       width,
-							Height:      height,
-							FrameFormat: supportedFormat,
-						},
-					})
-				}
-			}
+			properties = append(properties, prop.Media{
+				Video: prop.Video{
+					Width:       int(frameSize.MaxWidth),
+					Height:      int(frameSize.MaxHeight),
+					FrameFormat: c.formats[format],
+				},
+			})
 		}
 	}
 	return properties
--- a/pkg/driver/camera/camera_windows.go
+++ b/pkg/driver/camera/camera_windows.go
@@ -116,10 +116,10 @@ func (c *camera) VideoRecord(p prop.Media) (video.Reader, error) {

 	img := &image.YCbCr{}

-	r := video.ReaderFunc(func() (image.Image, func(), error) {
+	r := video.ReaderFunc(func() (image.Image, error) {
 		b, ok := <-c.ch
 		if !ok {
-			return nil, func() {}, io.EOF
+			return nil, io.EOF
 		}
 		img.Y = b[:nPix]
 		img.Cb = b[nPix : nPix+nPix/2]
@@ -128,7 +128,7 @@ func (c *camera) VideoRecord(p prop.Media) (video.Reader, error) {
 		img.CStride = p.Width / 2
 		img.SubsampleRatio = image.YCbCrSubsampleRatio422
 		img.Rect = image.Rect(0, 0, p.Width, p.Height)
-		return img, func() {}, nil
+		return img, nil
 	})
 	return r, nil
 }
--- a/pkg/driver/microphone/microphone.go
+++ b/pkg/driver/microphone/microphone.go
@@ -1,200 +1 @@
 package microphone
-
-import (
-	"encoding/binary"
-	"errors"
-	"fmt"
-	"io"
-	"time"
-	"unsafe"
-
-	"github.com/gen2brain/malgo"
-	"github.com/pion/mediadevices/internal/logging"
-	"github.com/pion/mediadevices/pkg/driver"
-	"github.com/pion/mediadevices/pkg/io/audio"
-	"github.com/pion/mediadevices/pkg/prop"
-	"github.com/pion/mediadevices/pkg/wave"
-)
-
-const (
-	maxDeviceIDLength = 20
-	// TODO: should replace this with a more flexible approach
-	sampleRateStep    = 1000
-	initialBufferSize = 1024
-)
-
-var logger = logging.NewLogger("mediadevices/driver/microphone")
-var ctx *malgo.AllocatedContext
-var hostEndian binary.ByteOrder
-var (
-	errUnsupportedFormat = errors.New("the provided audio format is not supported")
-)
-
-type microphone struct {
-	malgo.DeviceInfo
-	chunkChan chan []byte
-}
-
-func init() {
-	var err error
-	ctx, err = malgo.InitContext(nil, malgo.ContextConfig{}, func(message string) {
-		logger.Debugf("%v\n", message)
-	})
-	if err != nil {
-		panic(err)
-	}
-
-	devices, err := ctx.Devices(malgo.Capture)
-	if err != nil {
-		panic(err)
-	}
-
-	for _, device := range devices {
-		info, err := ctx.DeviceInfo(malgo.Capture, device.ID, malgo.Shared)
-		if err == nil {
-			priority := driver.PriorityNormal
-			if info.IsDefault > 0 {
-				priority = driver.PriorityHigh
-			}
-			driver.GetManager().Register(newMicrophone(info), driver.Info{
-				Label:      device.ID.String(),
-				DeviceType: driver.Microphone,
-				Priority:   priority,
-			})
-		}
-	}
-
-	// Decide which endian
-	switch v := *(*uint16)(unsafe.Pointer(&([]byte{0x12, 0x34}[0]))); v {
-	case 0x1234:
-		hostEndian = binary.BigEndian
-	case 0x3412:
-		hostEndian = binary.LittleEndian
-	default:
-		panic(fmt.Sprintf("failed to determine host endianness: %x", v))
-	}
-}
-
-func newMicrophone(info malgo.DeviceInfo) *microphone {
-	return &microphone{
-		DeviceInfo: info,
-	}
-}
-
-func (m *microphone) Open() error {
-	m.chunkChan = make(chan []byte, 1)
-	return nil
-}
-
-func (m *microphone) Close() error {
-	if m.chunkChan != nil {
-		close(m.chunkChan)
-		m.chunkChan = nil
-	}
-	return nil
-}
-
-func (m *microphone) AudioRecord(inputProp prop.Media) (audio.Reader, error) {
-	var config malgo.DeviceConfig
-	var callbacks malgo.DeviceCallbacks
-
-	decoder, err := wave.NewDecoder(&wave.RawFormat{
-		SampleSize:  inputProp.SampleSize,
-		IsFloat:     inputProp.IsFloat,
-		Interleaved: inputProp.IsInterleaved,
-	})
-	if err != nil {
-		return nil, err
-	}
-
-	config.DeviceType = malgo.Capture
-	config.PerformanceProfile = malgo.LowLatency
-	config.Capture.Channels = uint32(inputProp.ChannelCount)
-	config.SampleRate = uint32(inputProp.SampleRate)
-	if inputProp.SampleSize == 4 && inputProp.IsFloat {
-		config.Capture.Format = malgo.FormatF32
-	} else if inputProp.SampleSize == 2 && !inputProp.IsFloat {
-		config.Capture.Format = malgo.FormatS16
-	} else {
-		return nil, errUnsupportedFormat
-	}
-
-	onRecvChunk := func(_, chunk []byte, framecount uint32) {
-		m.chunkChan <- chunk
-	}
-	callbacks.Data = onRecvChunk
-
-	device, err := malgo.InitDevice(ctx.Context, config, callbacks)
-	if err != nil {
-		return nil, err
-	}
-
-	err = device.Start()
-	if err != nil {
-		return nil, err
-	}
-
-	var reader audio.Reader = audio.ReaderFunc(func() (wave.Audio, func(), error) {
-		chunk, ok := <-m.chunkChan
-		if !ok {
-			device.Stop()
-			device.Uninit()
-			return nil, func() {}, io.EOF
-		}
-
-		decodedChunk, err := decoder.Decode(hostEndian, chunk, inputProp.ChannelCount)
-		// FIXME: the decoder should also fill this information
-		decodedChunk.(*wave.Float32Interleaved).Size.SamplingRate = inputProp.SampleRate
-		return decodedChunk, func() {}, err
-	})
-
-	// FIXME: The current audio detection and audio encoder can only work with a static latency. Since the latency from the driver
-	//        can fluctuate, we need to stabilize it. Maybe there's a better way for doing this?
-	reader = audio.NewBuffer(int(inputProp.Latency.Seconds() * float64(inputProp.SampleRate)))(reader)
-	return reader, nil
-}
-
-func (m *microphone) Properties() []prop.Media {
-	var supportedProps []prop.Media
-	logger.Debug("Querying properties")
-
-	var isBigEndian bool
-	// miniaudio only uses the host endian
-	if hostEndian == binary.BigEndian {
-		isBigEndian = true
-	}
-
-	for ch := m.MinChannels; ch <= m.MaxChannels; ch++ {
-		// FIXME: Currently support 48kHz only. We need to implement a resampler first.
-		// for sampleRate := m.MinSampleRate; sampleRate <= m.MaxSampleRate; sampleRate += sampleRateStep {
-		sampleRate := 48000
-		for i := 0; i < int(m.FormatCount); i++ {
-			format := m.Formats[i]
-
-			supportedProp := prop.Media{
-				Audio: prop.Audio{
-					ChannelCount: int(ch),
-					SampleRate:   int(sampleRate),
-					IsBigEndian:  isBigEndian,
-					// miniaudio only supports interleaved at the moment
-					IsInterleaved: true,
-					// FIXME: should change this to a less discrete value
-					Latency: time.Millisecond * 20,
-				},
-			}
-
-			switch malgo.FormatType(format) {
-			case malgo.FormatF32:
-				supportedProp.SampleSize = 4
-				supportedProp.IsFloat = true
-			case malgo.FormatS16:
-				supportedProp.SampleSize = 2
-				supportedProp.IsFloat = false
-			}
-
-			supportedProps = append(supportedProps, supportedProp)
-		}
-		// }
-	}
-	return supportedProps
-}
--- a/pkg/driver/microphone/microphone_linux.go
+++ b/pkg/driver/microphone/microphone_linux.go
@@ -0,0 +1,137 @@
+package microphone
+
+import (
+	"io"
+	"time"
+
+	"github.com/jfreymuth/pulse"
+	"github.com/pion/mediadevices/pkg/driver"
+	"github.com/pion/mediadevices/pkg/io/audio"
+	"github.com/pion/mediadevices/pkg/prop"
+	"github.com/pion/mediadevices/pkg/wave"
+)
+
+type microphone struct {
+	c           *pulse.Client
+	id          string
+	samplesChan chan<- []int16
+}
+
+func init() {
+	pa, err := pulse.NewClient()
+	if err != nil {
+		// No pulseaudio
+		return
+	}
+	defer pa.Close()
+	sources, err := pa.ListSources()
+	if err != nil {
+		panic(err)
+	}
+	defaultSource, err := pa.DefaultSource()
+	if err != nil {
+		panic(err)
+	}
+	for _, source := range sources {
+		priority := driver.PriorityNormal
+		if defaultSource.ID() == source.ID() {
+			priority = driver.PriorityHigh
+		}
+		driver.GetManager().Register(&microphone{id: source.ID()}, driver.Info{
+			Label:      source.ID(),
+			DeviceType: driver.Microphone,
+			Priority:   priority,
+		})
+	}
+}
+
+func (m *microphone) Open() error {
+	var err error
+	m.c, err = pulse.NewClient()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (m *microphone) Close() error {
+	if m.samplesChan != nil {
+		close(m.samplesChan)
+		m.samplesChan = nil
+	}
+
+	m.c.Close()
+	return nil
+}
+
+func (m *microphone) AudioRecord(p prop.Media) (audio.Reader, error) {
+	var options []pulse.RecordOption
+	if p.ChannelCount == 1 {
+		options = append(options, pulse.RecordMono)
+	} else {
+		options = append(options, pulse.RecordStereo)
+	}
+	latency := p.Latency.Seconds()
+
+	src, err := m.c.SourceByID(m.id)
+	if err != nil {
+		return nil, err
+	}
+
+	options = append(options,
+		pulse.RecordSampleRate(p.SampleRate),
+		pulse.RecordLatency(latency),
+		pulse.RecordSource(src),
+	)
+
+	samplesChan := make(chan []int16, 1)
+
+	handler := func(b []int16) (int, error) {
+		samplesChan <- b
+		return len(b), nil
+	}
+
+	stream, err := m.c.NewRecord(pulse.Int16Writer(handler), options...)
+	if err != nil {
+		return nil, err
+	}
+
+	reader := audio.ReaderFunc(func() (wave.Audio, error) {
+		buff, ok := <-samplesChan
+		if !ok {
+			stream.Close()
+			return nil, io.EOF
+		}
+
+		a := wave.NewInt16Interleaved(
+			wave.ChunkInfo{
+				Channels: p.ChannelCount,
+				Len:      len(buff) / p.ChannelCount,
+			},
+		)
+		copy(a.Data, buff)
+
+		return a, nil
+	})
+
+	stream.Start()
+	m.samplesChan = samplesChan
+	return reader, nil
+}
+
+func (m *microphone) Properties() []prop.Media {
+	// TODO: Get actual properties
+	monoProp := prop.Media{
+		Audio: prop.Audio{
+			SampleRate:   48000,
+			Latency:      time.Millisecond * 20,
+			ChannelCount: 1,
+		},
+	}
+
+	stereoProp := monoProp
+	stereoProp.ChannelCount = 2
+
+	return []prop.Media{monoProp, stereoProp}
+}
--- a/pkg/driver/microphone/microphone_windows.go
+++ b/pkg/driver/microphone/microphone_windows.go
@@ -0,0 +1,347 @@
+package microphone
+
+import (
+	"errors"
+	"golang.org/x/sys/windows"
+	"io"
+	"time"
+	"unsafe"
+
+	"github.com/pion/mediadevices/pkg/driver"
+	"github.com/pion/mediadevices/pkg/io/audio"
+	"github.com/pion/mediadevices/pkg/prop"
+	"github.com/pion/mediadevices/pkg/wave"
+)
+
+const (
+	// bufferNumber * prop.Audio.Latency is the maximum blockable duration
+	// to get data without dropping chunks.
+	bufferNumber = 5
+)
+
+// Windows APIs
+var (
+	winmm                 = windows.NewLazySystemDLL("Winmm.dll")
+	waveInOpen            = winmm.NewProc("waveInOpen")
+	waveInStart           = winmm.NewProc("waveInStart")
+	waveInStop            = winmm.NewProc("waveInStop")
+	waveInReset           = winmm.NewProc("waveInReset")
+	waveInClose           = winmm.NewProc("waveInClose")
+	waveInPrepareHeader   = winmm.NewProc("waveInPrepareHeader")
+	waveInAddBuffer       = winmm.NewProc("waveInAddBuffer")
+	waveInUnprepareHeader = winmm.NewProc("waveInUnprepareHeader")
+)
+
+type buffer struct {
+	waveHdr
+	data []int16
+}
+
+func newBuffer(samples int) *buffer {
+	b := make([]int16, samples)
+	return &buffer{
+		waveHdr: waveHdr{
+			// Sharing Go memory with Windows C API without reference.
+			// Make sure that the lifetime of the buffer struct is longer
+			// than the final access from cbWaveIn.
+			lpData:         uintptr(unsafe.Pointer(&b[0])),
+			dwBufferLength: uint32(samples * 2),
+		},
+		data: b,
+	}
+}
+
+type microphone struct {
+	hWaveIn windows.Pointer
+	buf     map[uintptr]*buffer
+	chBuf   chan *buffer
+	closed  chan struct{}
+}
+
+func init() {
+	// TODO: enum devices
+	driver.GetManager().Register(&microphone{}, driver.Info{
+		Label:      "default",
+		DeviceType: driver.Microphone,
+	})
+}
+
+func (m *microphone) Open() error {
+	m.chBuf = make(chan *buffer)
+	m.buf = make(map[uintptr]*buffer)
+	m.closed = make(chan struct{})
+	return nil
+}
+
+func (m *microphone) cbWaveIn(hWaveIn windows.Pointer, uMsg uint, dwInstance, dwParam1, dwParam2 *int32) uintptr {
+	switch uMsg {
+	case MM_WIM_DATA:
+		b := m.buf[uintptr(unsafe.Pointer(dwParam1))]
+		m.chBuf <- b
+
+	case MM_WIM_OPEN:
+	case MM_WIM_CLOSE:
+		close(m.chBuf)
+	}
+	return 0
+}
+
+func (m *microphone) Close() error {
+	if m.hWaveIn == nil {
+		return nil
+	}
+	close(m.closed)
+
+	ret, _, _ := waveInStop.Call(
+		uintptr(unsafe.Pointer(m.hWaveIn)),
+	)
+	if err := errWinmm[ret]; err != nil {
+		return err
+	}
+	// All enqueued buffers are marked done by waveInReset.
+	ret, _, _ = waveInReset.Call(
+		uintptr(unsafe.Pointer(m.hWaveIn)),
+	)
+	if err := errWinmm[ret]; err != nil {
+		return err
+	}
+	for _, buf := range m.buf {
+		// Detach buffers from waveIn API.
+		ret, _, _ := waveInUnprepareHeader.Call(
+			uintptr(unsafe.Pointer(m.hWaveIn)),
+			uintptr(unsafe.Pointer(&buf.waveHdr)),
+			uintptr(unsafe.Sizeof(buf.waveHdr)),
+		)
+		if err := errWinmm[ret]; err != nil {
+			return err
+		}
+	}
+	// Now, it's ready to free the buffers.
+	// As microphone struct still has reference to the buffers,
+	// they will be GC-ed once microphone is reopened or unreferenced.
+
+	ret, _, _ = waveInClose.Call(
+		uintptr(unsafe.Pointer(m.hWaveIn)),
+	)
+	if err := errWinmm[ret]; err != nil {
+		return err
+	}
+	<-m.chBuf
+	m.hWaveIn = nil
+
+	return nil
+}
+
+func (m *microphone) AudioRecord(p prop.Media) (audio.Reader, error) {
+	for i := 0; i < bufferNumber; i++ {
+		b := newBuffer(
+			int(uint64(p.Latency) * uint64(p.SampleRate) / uint64(time.Second)),
+		)
+		// Map the buffer by its data head address to restore access to the Go struct
+		// in callback function. Don't resize the buffer after it.
+		m.buf[uintptr(unsafe.Pointer(&b.waveHdr))] = b
+	}
+
+	waveFmt := &waveFormatEx{
+		wFormatTag:      WAVE_FORMAT_PCM,
+		nChannels:       uint16(p.ChannelCount),
+		nSamplesPerSec:  uint32(p.SampleRate),
+		nAvgBytesPerSec: uint32(p.SampleRate * p.ChannelCount * 2),
+		nBlockAlign:     uint16(p.ChannelCount * 2),
+		wBitsPerSample:  16,
+	}
+	ret, _, _ := waveInOpen.Call(
+		uintptr(unsafe.Pointer(&m.hWaveIn)),
+		WAVE_MAPPER,
+		uintptr(unsafe.Pointer(waveFmt)),
+		windows.NewCallback(m.cbWaveIn),
+		0,
+		CALLBACK_FUNCTION,
+	)
+	if err := errWinmm[ret]; err != nil {
+		return nil, err
+	}
+
+	for _, buf := range m.buf {
+		// Attach buffers to waveIn API.
+		ret, _, _ := waveInPrepareHeader.Call(
+			uintptr(unsafe.Pointer(m.hWaveIn)),
+			uintptr(unsafe.Pointer(&buf.waveHdr)),
+			uintptr(unsafe.Sizeof(buf.waveHdr)),
+		)
+		if err := errWinmm[ret]; err != nil {
+			return nil, err
+		}
+	}
+	for _, buf := range m.buf {
+		// Enqueue buffers.
+		ret, _, _ := waveInAddBuffer.Call(
+			uintptr(unsafe.Pointer(m.hWaveIn)),
+			uintptr(unsafe.Pointer(&buf.waveHdr)),
+			uintptr(unsafe.Sizeof(buf.waveHdr)),
+		)
+		if err := errWinmm[ret]; err != nil {
+			return nil, err
+		}
+	}
+
+	ret, _, _ = waveInStart.Call(
+		uintptr(unsafe.Pointer(m.hWaveIn)),
+	)
+	if err := errWinmm[ret]; err != nil {
+		return nil, err
+	}
+
+	// TODO: detect microphone device disconnection and return EOF
+
+	reader := audio.ReaderFunc(func() (wave.Audio, error) {
+		b, ok := <-m.chBuf
+		if !ok {
+			return nil, io.EOF
+		}
+
+		select {
+		case <-m.closed:
+		default:
+			// Re-enqueue used buffer.
+			ret, _, _ := waveInAddBuffer.Call(
+				uintptr(unsafe.Pointer(m.hWaveIn)),
+				uintptr(unsafe.Pointer(&b.waveHdr)),
+				uintptr(unsafe.Sizeof(b.waveHdr)),
+			)
+			if err := errWinmm[ret]; err != nil {
+				return nil, err
+			}
+		}
+
+		a := wave.NewInt16Interleaved(
+			wave.ChunkInfo{
+				Channels: p.ChannelCount,
+				Len:      (int(b.waveHdr.dwBytesRecorded) / 2) / p.ChannelCount,
+			},
+		)
+
+		j := 0
+		for i := 0; i < a.Size.Len; i++ {
+			for ch := 0; ch < a.Size.Channels; ch++ {
+				a.SetInt16(i, ch, wave.Int16Sample(b.data[j]))
+				j++
+			}
+		}
+
+		return a, nil
+	})
+	return reader, nil
+}
+
+func (m *microphone) Properties() []prop.Media {
+	// TODO: Get actual properties
+	monoProp := prop.Media{
+		Audio: prop.Audio{
+			SampleRate:   48000,
+			Latency:      time.Millisecond * 20,
+			ChannelCount: 1,
+		},
+	}
+
+	stereoProp := monoProp
+	stereoProp.ChannelCount = 2
+
+	return []prop.Media{monoProp, stereoProp}
+}
+
+// Windows API structures
+
+type waveFormatEx struct {
+	wFormatTag      uint16
+	nChannels       uint16
+	nSamplesPerSec  uint32
+	nAvgBytesPerSec uint32
+	nBlockAlign     uint16
+	wBitsPerSample  uint16
+	cbSize          uint16
+}
+
+type waveHdr struct {
+	lpData          uintptr
+	dwBufferLength  uint32
+	dwBytesRecorded uint32
+	dwUser          *uint32
+	dwFlags         uint32
+	dwLoops         uint32
+	lpNext          *waveHdr
+	reserved        *uint32
+}
+
+// Windows consts
+
+const (
+	MMSYSERR_NOERROR      = 0
+	MMSYSERR_ERROR        = 1
+	MMSYSERR_BADDEVICEID  = 2
+	MMSYSERR_NOTENABLED   = 3
+	MMSYSERR_ALLOCATED    = 4
+	MMSYSERR_INVALHANDLE  = 5
+	MMSYSERR_NODRIVER     = 6
+	MMSYSERR_NOMEM        = 7
+	MMSYSERR_NOTSUPPORTED = 8
+	MMSYSERR_BADERRNUM    = 9
+	MMSYSERR_INVALFLAG    = 10
+	MMSYSERR_INVALPARAM   = 11
+	MMSYSERR_HANDLEBUSY   = 12
+	MMSYSERR_INVALIDALIAS = 13
+	MMSYSERR_BADDB        = 14
+	MMSYSERR_KEYNOTFOUND  = 15
+	MMSYSERR_READERROR    = 16
+	MMSYSERR_WRITEERROR   = 17
+	MMSYSERR_DELETEERROR  = 18
+	MMSYSERR_VALNOTFOUND  = 19
+	MMSYSERR_NODRIVERCB   = 20
+
+	WAVERR_BADFORMAT    = 32
+	WAVERR_STILLPLAYING = 33
+	WAVERR_UNPREPARED   = 34
+	WAVERR_SYNC         = 35
+
+	WAVE_MAPPER     = 0xFFFF
+	WAVE_FORMAT_PCM = 1
+
+	CALLBACK_NULL     = 0
+	CALLBACK_WINDOW   = 0x10000
+	CALLBACK_TASK     = 0x20000
+	CALLBACK_FUNCTION = 0x30000
+	CALLBACK_THREAD   = CALLBACK_TASK
+	CALLBACK_EVENT    = 0x50000
+
+	MM_WIM_OPEN  = 0x3BE
+	MM_WIM_CLOSE = 0x3BF
+	MM_WIM_DATA  = 0x3C0
+)
+
+var errWinmm = map[uintptr]error{
+	MMSYSERR_NOERROR:      nil,
+	MMSYSERR_ERROR:        errors.New("error"),
+	MMSYSERR_BADDEVICEID:  errors.New("bad device id"),
+	MMSYSERR_NOTENABLED:   errors.New("not enabled"),
+	MMSYSERR_ALLOCATED:    errors.New("already allocated"),
+	MMSYSERR_INVALHANDLE:  errors.New("invalid handler"),
+	MMSYSERR_NODRIVER:     errors.New("no driver"),
+	MMSYSERR_NOMEM:        errors.New("no memory"),
+	MMSYSERR_NOTSUPPORTED: errors.New("not supported"),
+	MMSYSERR_BADERRNUM:    errors.New("band error number"),
+	MMSYSERR_INVALFLAG:    errors.New("invalid flag"),
+	MMSYSERR_INVALPARAM:   errors.New("invalid param"),
+	MMSYSERR_HANDLEBUSY:   errors.New("handle busy"),
+	MMSYSERR_INVALIDALIAS: errors.New("invalid alias"),
+	MMSYSERR_BADDB:        errors.New("bad db"),
+	MMSYSERR_KEYNOTFOUND:  errors.New("key not found"),
+	MMSYSERR_READERROR:    errors.New("read error"),
+	MMSYSERR_WRITEERROR:   errors.New("write error"),
+	MMSYSERR_DELETEERROR:  errors.New("delete error"),
+	MMSYSERR_VALNOTFOUND:  errors.New("value not found"),
+	MMSYSERR_NODRIVERCB:   errors.New("no driver cb"),
+	WAVERR_BADFORMAT:      errors.New("bad format"),
+	WAVERR_STILLPLAYING:   errors.New("still playing"),
+	WAVERR_UNPREPARED:     errors.New("unprepared"),
+	WAVERR_SYNC:           errors.New("sync"),
+}
--- a/pkg/driver/screen/screen.go
+++ b/pkg/driver/screen/screen.go
@@ -1,79 +1 @@
 package screen
-
-import (
-	"fmt"
-	"image"
-	"io"
-
-	"github.com/kbinani/screenshot"
-	"github.com/pion/mediadevices/pkg/driver"
-	"github.com/pion/mediadevices/pkg/frame"
-	"github.com/pion/mediadevices/pkg/io/video"
-	"github.com/pion/mediadevices/pkg/prop"
-)
-
-type screen struct {
-	displayIndex int
-	doneCh       chan struct{}
-}
-
-func init() {
-	activeDisplays := screenshot.NumActiveDisplays()
-	for i := 0; i < activeDisplays; i++ {
-		priority := driver.PriorityNormal
-		if i == 0 {
-			priority = driver.PriorityHigh
-		}
-
-		s := newScreen(i)
-		driver.GetManager().Register(s, driver.Info{
-			Label:      fmt.Sprint(i),
-			DeviceType: driver.Screen,
-			Priority:   priority,
-		})
-	}
-}
-
-func newScreen(displayIndex int) *screen {
-	s := screen{
-		displayIndex: displayIndex,
-	}
-	return &s
-}
-
-func (s *screen) Open() error {
-	s.doneCh = make(chan struct{})
-	return nil
-}
-
-func (s *screen) Close() error {
-	close(s.doneCh)
-	return nil
-}
-
-func (s *screen) VideoRecord(selectedProp prop.Media) (video.Reader, error) {
-	r := video.ReaderFunc(func() (img image.Image, release func(), err error) {
-		select {
-		case <-s.doneCh:
-			return nil, nil, io.EOF
-		default:
-		}
-
-		img, err = screenshot.CaptureDisplay(s.displayIndex)
-		release = func() {}
-		return
-	})
-	return r, nil
-}
-
-func (s *screen) Properties() []prop.Media {
-	resolution := screenshot.GetDisplayBounds(s.displayIndex)
-	supportedProp := prop.Media{
-		Video: prop.Video{
-			Width:       resolution.Dx(),
-			Height:      resolution.Dy(),
-			FrameFormat: frame.FormatRGBA,
-		},
-	}
-	return []prop.Media{supportedProp}
-}
--- a/pkg/driver/screen/x11_linux.go
+++ b/pkg/driver/screen/x11_linux.go
@@ -0,0 +1,92 @@
+package screen
+
+import (
+	"fmt"
+	"image"
+	"time"
+
+	"github.com/pion/mediadevices/pkg/driver"
+	"github.com/pion/mediadevices/pkg/frame"
+	"github.com/pion/mediadevices/pkg/io/video"
+	"github.com/pion/mediadevices/pkg/prop"
+)
+
+type screen struct {
+	num    int
+	reader *reader
+	tick   *time.Ticker
+}
+
+func deviceID(num int) string {
+	return fmt.Sprintf("X11Screen%d", num)
+}
+
+func init() {
+	dp, err := openDisplay()
+	if err != nil {
+		// No x11 display available.
+		return
+	}
+	defer dp.Close()
+	numScreen := dp.NumScreen()
+	for i := 0; i < numScreen; i++ {
+		driver.GetManager().Register(
+			&screen{
+				num: i,
+			},
+			driver.Info{
+				Label:      deviceID(i),
+				DeviceType: driver.Screen,
+			},
+		)
+	}
+}
+
+func (s *screen) Open() error {
+	r, err := newReader(s.num)
+	if err != nil {
+		return err
+	}
+	s.reader = r
+	return nil
+}
+
+func (s *screen) Close() error {
+	s.reader.Close()
+	if s.tick != nil {
+		s.tick.Stop()
+	}
+	return nil
+}
+
+func (s *screen) VideoRecord(p prop.Media) (video.Reader, error) {
+	if p.FrameRate == 0 {
+		p.FrameRate = 10
+	}
+	s.tick = time.NewTicker(time.Duration(float32(time.Second) / p.FrameRate))
+
+	var dst image.RGBA
+	reader := s.reader
+
+	r := video.ReaderFunc(func() (image.Image, error) {
+		<-s.tick.C
+		return reader.Read().ToRGBA(&dst), nil
+	})
+	return r, nil
+}
+
+func (s *screen) Properties() []prop.Media {
+	rect := s.reader.img.Bounds()
+	w := rect.Dx()
+	h := rect.Dy()
+	return []prop.Media{
+		{
+			DeviceID: deviceID(s.num),
+			Video: prop.Video{
+				Width:       w,
+				Height:      h,
+				FrameFormat: frame.FormatRGBA,
+			},
+		},
+	}
+}
--- a/pkg/driver/screen/x11capture_linux.go
+++ b/pkg/driver/screen/x11capture_linux.go
@@ -0,0 +1,283 @@
+package screen
+
+// #cgo pkg-config: x11 xext
+// #include <stdint.h>
+// #include <sys/shm.h>
+// #include <X11/Xlib.h>
+// #define XUTIL_DEFINE_FUNCTIONS
+// #include <X11/Xutil.h>
+// #include <X11/extensions/XShm.h>
+//
+// void copyBGR24(void *dst, char *src, size_t l) { // 64bit aligned copy
+//   uint64_t *d = (uint64_t*)dst;
+//   uint64_t *s = (uint64_t*)src;
+//   l /= 8;
+//   for (size_t i = 0; i < l; i ++) {
+//     uint64_t v = *s;
+//     // Reorder BGR to RGB
+//     *d = 0xFF000000FF000000 |
+//          ((v >> 16) & 0xFF00000000) | (v & 0xFF0000000000) | ((v & 0xFF00000000) << 16) |
+//          ((v >> 16) & 0xFF) | (v & 0xFF00) | ((v & 0xFF) << 16);
+//     d++;
+//     s++;
+//   }
+// }
+//
+// void copyBGR16(void *dst, char *src, size_t l) { // 64bit aligned copy
+//   uint64_t *d = (uint64_t*)dst;
+//   uint32_t *s = (uint32_t*)src;
+//   l /= 8;
+//   for (size_t i = 0; i < l; i ++) {
+//     uint64_t v = *s;
+//     // Reorder BGR to RGB
+//     *d = 0xFF000000FF000000 |
+//          ((v & 0xF8000000) << 8)  | ((v & 0x7E00000) << 21) | ((v & 0x1F0000) << 35) |
+//          ((v & 0xF800) >> 8) | ((v & 0x7E0) << 5) | ((v & 0x1F) << 19);
+//     d++;
+//     s++;
+//   }
+// }
+//
+// char *align64(char *ptr) { // return 64bit aligned pointer
+//   if (((size_t)ptr & 0x07) == 0) {
+//     return ptr;
+//   }
+//   // Clear lower 3bits to align the address to 8bytes.
+//   return (char*)(((size_t)ptr & (~(size_t)0x07)) + 0x08);
+// }
+// size_t align64ForTest(size_t ptr) {
+//   return (size_t)align64((char*)ptr);
+// }
+import "C"
+
+import (
+	"errors"
+	"fmt"
+	"image"
+	"image/color"
+	"unsafe"
+)
+
+const shmaddrInvalid = ^uintptr(0)
+
+type display C.Display
+
+type pixelFormat int
+
+const (
+	pixFmtBGR24 pixelFormat = iota
+	pixFmtRGB24
+	pixFmtBGR16
+	pixFmtRGB16
+)
+
+func openDisplay() (*display, error) {
+	dp := C.XOpenDisplay(nil)
+	if dp == nil {
+		return nil, errors.New("failed to open display")
+	}
+	return (*display)(dp), nil
+}
+
+func (d *display) c() *C.Display {
+	return (*C.Display)(d)
+}
+
+func (d *display) Close() {
+	C.XCloseDisplay(d.c())
+}
+
+func (d *display) NumScreen() int {
+	return int(C.XScreenCount(d.c()))
+}
+
+type shmImage struct {
+	dp     *C.Display
+	img    *C.XImage
+	shm    C.XShmSegmentInfo
+	b      []byte
+	pixFmt pixelFormat
+}
+
+func (s *shmImage) Free() {
+	if s.img != nil {
+		C.XShmDetach(s.dp, &s.shm)
+		C.XDestroyImage(s.img)
+	}
+	if uintptr(unsafe.Pointer(s.shm.shmaddr)) != shmaddrInvalid {
+		C.shmdt(unsafe.Pointer(s.shm.shmaddr))
+	}
+}
+
+func (s *shmImage) ColorModel() color.Model {
+	return color.RGBAModel
+}
+
+func (s *shmImage) Bounds() image.Rectangle {
+	return image.Rect(0, 0, int(s.img.width), int(s.img.height))
+}
+
+type colorFunc func() (r, g, b, a uint32)
+
+func (c colorFunc) RGBA() (r, g, b, a uint32) {
+	return c()
+}
+
+func (s *shmImage) At(x, y int) color.Color {
+	switch s.pixFmt {
+	case pixFmtBGR24:
+		addr := (x + y*int(s.img.width)) * 4
+		b := uint32(s.b[addr]) * 0x100
+		g := uint32(s.b[addr+1]) * 0x100
+		r := uint32(s.b[addr+2]) * 0x100
+		return colorFunc(func() (_, _, _, _ uint32) {
+			return r, g, b, 0xFFFF
+		})
+	case pixFmtBGR16:
+		addr := (x + y*int(s.img.width)) * 2
+		b1, b2 := s.b[addr], s.b[addr+1]
+		b := uint32(b1>>3) * 0x100
+		g := uint32((b1&0x7)<<3|(b2&0xE0)>>5) * 0x100
+		r := uint32(b2&0x1F) * 0x100
+		return colorFunc(func() (_, _, _, _ uint32) {
+			return r, g, b, 0xFFFF
+		})
+	default:
+		panic("unsupported pixel format")
+	}
+}
+
+func (s *shmImage) RGBAAt(x, y int) color.RGBA {
+	switch s.pixFmt {
+	case pixFmtBGR24:
+		addr := (x + y*int(s.img.width)) * 4
+		b := s.b[addr]
+		g := s.b[addr+1]
+		r := s.b[addr+2]
+		return color.RGBA{R: r, G: g, B: b, A: 0xFF}
+	case pixFmtBGR16:
+		addr := (x + y*int(s.img.width)) * 2
+		b1, b2 := s.b[addr], s.b[addr+1]
+		b := b1 >> 3
+		g := (b1&0x7)<<3 | (b2&0xE0)>>5
+		r := b2 & 0x1F
+		return color.RGBA{R: r, G: g, B: b, A: 0xFF}
+	default:
+		panic("unsupported pixel format")
+	}
+}
+
+func (s *shmImage) ToRGBA(dst *image.RGBA) *image.RGBA {
+	dst.Rect = s.Bounds()
+	dst.Stride = int(s.img.width) * 4
+	l := int(4 * s.img.width * s.img.height)
+	if len(dst.Pix) < l {
+		if cap(dst.Pix) < l {
+			dst.Pix = make([]uint8, l)
+		}
+		dst.Pix = dst.Pix[:l]
+	}
+	switch s.pixFmt {
+	case pixFmtBGR24:
+		C.copyBGR24(unsafe.Pointer(&dst.Pix[0]), s.img.data, C.ulong(len(dst.Pix)))
+		return dst
+	case pixFmtBGR16:
+		C.copyBGR16(unsafe.Pointer(&dst.Pix[0]), s.img.data, C.ulong(len(dst.Pix)))
+		return dst
+	default:
+		panic("unsupported pixel format")
+	}
+}
+
+func newShmImage(dp *C.Display, screen int) (*shmImage, error) {
+	cScreen := C.int(screen)
+	w := int(C.XDisplayWidth(dp, cScreen))
+	h := int(C.XDisplayHeight(dp, cScreen))
+	v := C.XDefaultVisual(dp, cScreen)
+	depth := int(C.XDefaultDepth(dp, cScreen))
+
+	s := &shmImage{dp: dp}
+
+	switch {
+	case v.red_mask == 0xFF0000 && v.green_mask == 0xFF00 && v.blue_mask == 0xFF:
+		s.pixFmt = pixFmtBGR24
+	case v.red_mask == 0xF800 && v.green_mask == 0x7E0 && v.blue_mask == 0x1F:
+		s.pixFmt = pixFmtBGR16
+	default:
+		fmt.Printf("x11capture: unsupported pixel format (R: %0x, G: %0x, B: %0x)\n",
+			v.red_mask, v.green_mask, v.blue_mask)
+		return nil, errors.New("unsupported pixel format")
+	}
+
+	s.shm.shmid = C.shmget(C.IPC_PRIVATE, C.ulong(w*h*4+8), C.IPC_CREAT|0600)
+	if s.shm.shmid == -1 {
+		return nil, errors.New("failed to get shared memory")
+	}
+	s.shm.shmaddr = (*C.char)(C.shmat(s.shm.shmid, unsafe.Pointer(nil), 0))
+	if uintptr(unsafe.Pointer(s.shm.shmaddr)) == shmaddrInvalid {
+		s.shm.shmaddr = nil
+		return nil, errors.New("failed to get shared memory address")
+	}
+	s.shm.readOnly = 0
+	C.shmctl(s.shm.shmid, C.IPC_RMID, nil)
+
+	s.img = C.XShmCreateImage(
+		dp, v, C.uint(depth), C.ZPixmap, C.align64(s.shm.shmaddr), &s.shm, C.uint(w), C.uint(h))
+	if s.img == nil {
+		s.Free()
+		return nil, errors.New("failed to create XShm image")
+	}
+	C.XShmAttach(dp, &s.shm)
+	C.XSync(dp, 0)
+
+	return s, nil
+}
+
+type reader struct {
+	dp  *C.Display
+	img *shmImage
+}
+
+func newReader(screen int) (*reader, error) {
+	dp := C.XOpenDisplay(nil)
+	if dp == nil {
+		return nil, errors.New("failed to open display")
+	}
+	if C.XShmQueryExtension(dp) == 0 {
+		return nil, errors.New("no XShm support")
+	}
+
+	img, err := newShmImage(dp, screen)
+	if err != nil {
+		C.XCloseDisplay(dp)
+		return nil, err
+	}
+
+	return &reader{
+		dp:  dp,
+		img: img,
+	}, nil
+}
+
+func (r *reader) Size() (int, int) {
+	return int(r.img.img.width), int(r.img.img.height)
+}
+
+func (r *reader) Read() *shmImage {
+	C.XShmGetImage(r.dp, C.XDefaultRootWindow(r.dp), r.img.img, 0, 0, C.AllPlanes)
+	r.img.b = C.GoBytes(
+		unsafe.Pointer(r.img.img.data),
+		C.int(r.img.img.width*r.img.img.height*4),
+	)
+	return r.img
+}
+
+func (r *reader) Close() {
+	r.img.Free()
+	C.XCloseDisplay(r.dp)
+}
+
+// cAlign64 is fot testing
+func cAlign64(ptr uintptr) uintptr {
+	return uintptr(C.align64ForTest(C.ulong(uintptr(ptr))))
+}
--- a/pkg/driver/screen/x11capture_linux_test.go
+++ b/pkg/driver/screen/x11capture_linux_test.go
@@ -0,0 +1,17 @@
+package screen
+
+import (
+	"testing"
+)
+
+func TestAlign64(t *testing.T) {
+	if ret := cAlign64(0x00010008); ret != 0x00010008 {
+		t.Errorf("Wrong alignment, expected %x, got %x", 0x00010008, ret)
+	}
+	if ret := cAlign64(0x00010006); ret != 0x00010008 {
+		t.Errorf("Wrong alignment, expected %x, got %x", 0x00010008, ret)
+	}
+	if ret := cAlign64(0x00010009); ret != 0x00010010 {
+		t.Errorf("Wrong alignment, expected %x, got %x", 0x00010010, ret)
+	}
+}
--- a/pkg/driver/videotest/dummy.go
+++ b/pkg/driver/videotest/dummy.go
@@ -103,10 +103,10 @@ func (d *dummy) VideoRecord(p prop.Media) (video.Reader, error) {
 	d.tick = tick
 	closed := d.closed

-	r := video.ReaderFunc(func() (image.Image, func(), error) {
+	r := video.ReaderFunc(func() (image.Image, error) {
 		select {
 		case <-closed:
-			return nil, func() {}, io.EOF
+			return nil, io.EOF
 		default:
 		}

@@ -130,7 +130,7 @@ func (d *dummy) VideoRecord(p prop.Media) (video.Reader, error) {
 			CStride:        p.Width / 2,
 			SubsampleRatio: image.YCbCrSubsampleRatio422,
 			Rect:           image.Rect(0, 0, p.Width, p.Height),
-		}, func() {}, nil
+		}, nil
 	})

 	return r, nil
--- a/pkg/frame/compressed.go
+++ b/pkg/frame/compressed.go
@@ -6,7 +6,6 @@ import (
 	"image/jpeg"
 )

-func decodeMJPEG(frame []byte, width, height int) (image.Image, func(), error) {
-	img, err := jpeg.Decode(bytes.NewReader(frame))
-	return img, func() {}, err
+func decodeMJPEG(frame []byte, width, height int) (image.Image, error) {
+	return jpeg.Decode(bytes.NewReader(frame))
 }
--- a/pkg/frame/frame.go
+++ b/pkg/frame/frame.go
@@ -3,12 +3,12 @@ package frame
 import "image"

 type Decoder interface {
-	Decode(frame []byte, width, height int) (image.Image, func(), error)
+	Decode(frame []byte, width, height int) (image.Image, error)
 }

 // DecoderFunc is a proxy type for Decoder
-type decoderFunc func(frame []byte, width, height int) (image.Image, func(), error)
+type decoderFunc func(frame []byte, width, height int) (image.Image, error)

-func (f decoderFunc) Decode(frame []byte, width, height int) (image.Image, func(), error) {
+func (f decoderFunc) Decode(frame []byte, width, height int) (image.Image, error) {
 	return f(frame, width, height)
 }
--- a/pkg/frame/yuv.go
+++ b/pkg/frame/yuv.go
@@ -5,13 +5,13 @@ import (
 	"image"
 )

-func decodeI420(frame []byte, width, height int) (image.Image, func(), error) {
+func decodeI420(frame []byte, width, height int) (image.Image, error) {
 	yi := width * height
 	cbi := yi + width*height/4
 	cri := cbi + width*height/4

 	if cri > len(frame) {
-		return nil, func() {}, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), cri)
+		return nil, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), cri)
 	}

 	return &image.YCbCr{
@@ -22,15 +22,15 @@ func decodeI420(frame []byte, width, height int) (image.Image, func(), error) {
 		CStride:        width / 2,
 		SubsampleRatio: image.YCbCrSubsampleRatio420,
 		Rect:           image.Rect(0, 0, width, height),
-	}, func() {}, nil
+	}, nil
 }

-func decodeNV21(frame []byte, width, height int) (image.Image, func(), error) {
+func decodeNV21(frame []byte, width, height int) (image.Image, error) {
 	yi := width * height
 	ci := yi + width*height/2

 	if ci > len(frame) {
-		return nil, func() {}, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), ci)
+		return nil, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), ci)
 	}

 	var cb, cr []byte
@@ -47,5 +47,5 @@ func decodeNV21(frame []byte, width, height int) (image.Image, func(), error) {
 		CStride:        width / 2,
 		SubsampleRatio: image.YCbCrSubsampleRatio420,
 		Rect:           image.Rect(0, 0, width, height),
-	}, func() {}, nil
+	}, nil
 }
--- a/pkg/frame/yuv_cgo.go
+++ b/pkg/frame/yuv_cgo.go
@@ -12,13 +12,13 @@ import (
 // void decodeUYVYCGO(uint8_t* y, uint8_t* cb, uint8_t* cr, uint8_t* uyvy, int width, int height);
 import "C"

-func decodeYUY2(frame []byte, width, height int) (image.Image, func(), error) {
+func decodeYUY2(frame []byte, width, height int) (image.Image, error) {
 	yi := width * height
 	ci := yi / 2
 	fi := yi + 2*ci

 	if len(frame) != fi {
-		return nil, func() {}, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), fi)
+		return nil, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), fi)
 	}

 	y := make([]byte, yi)
@@ -41,16 +41,16 @@ func decodeYUY2(frame []byte, width, height int) (image.Image, func(), error) {
 		CStride:        width / 2,
 		SubsampleRatio: image.YCbCrSubsampleRatio422,
 		Rect:           image.Rect(0, 0, width, height),
-	}, func() {}, nil
+	}, nil
 }

-func decodeUYVY(frame []byte, width, height int) (image.Image, func(), error) {
+func decodeUYVY(frame []byte, width, height int) (image.Image, error) {
 	yi := width * height
 	ci := yi / 2
 	fi := yi + 2*ci

 	if len(frame) != fi {
-		return nil, func() {}, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), fi)
+		return nil, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), fi)
 	}

 	y := make([]byte, yi)
@@ -73,5 +73,5 @@ func decodeUYVY(frame []byte, width, height int) (image.Image, func(), error) {
 		CStride:        width / 2,
 		SubsampleRatio: image.YCbCrSubsampleRatio422,
 		Rect:           image.Rect(0, 0, width, height),
-	}, func() {}, nil
+	}, nil
 }
--- a/pkg/frame/yuv_nocgo.go
+++ b/pkg/frame/yuv_nocgo.go
@@ -7,13 +7,13 @@ import (
 	"image"
 )

-func decodeYUY2(frame []byte, width, height int) (image.Image, func(), error) {
+func decodeYUY2(frame []byte, width, height int) (image.Image, error) {
 	yi := width * height
 	ci := yi / 2
 	fi := yi + 2*ci

 	if len(frame) != fi {
-		return nil, func() {}, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), fi)
+		return nil, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), fi)
 	}

 	y := make([]byte, yi)
@@ -39,16 +39,16 @@ func decodeYUY2(frame []byte, width, height int) (image.Image, func(), error) {
 		CStride:        width / 2,
 		SubsampleRatio: image.YCbCrSubsampleRatio422,
 		Rect:           image.Rect(0, 0, width, height),
-	}, func() {}, nil
+	}, nil
 }

-func decodeUYVY(frame []byte, width, height int) (image.Image, func(), error) {
+func decodeUYVY(frame []byte, width, height int) (image.Image, error) {
 	yi := width * height
 	ci := yi / 2
 	fi := yi + 2*ci

 	if len(frame) != fi {
-		return nil, func() {}, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), fi)
+		return nil, fmt.Errorf("frame length (%d) less than expected (%d)", len(frame), fi)
 	}

 	y := make([]byte, yi)
@@ -74,5 +74,5 @@ func decodeUYVY(frame []byte, width, height int) (image.Image, func(), error) {
 		CStride:        width / 2,
 		SubsampleRatio: image.YCbCrSubsampleRatio422,
 		Rect:           image.Rect(0, 0, width, height),
-	}, func() {}, nil
+	}, nil
 }
--- a/pkg/frame/yuv_test.go
+++ b/pkg/frame/yuv_test.go
@@ -27,7 +27,7 @@ func TestDecodeYUY2(t *testing.T) {
 		Rect:           image.Rect(0, 0, width, height),
 	}

-	img, _, err := decodeYUY2(input, width, height)
+	img, err := decodeYUY2(input, width, height)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -56,7 +56,7 @@ func TestDecodeUYVY(t *testing.T) {
 		Rect:           image.Rect(0, 0, width, height),
 	}

-	img, _, err := decodeUYVY(input, width, height)
+	img, err := decodeUYVY(input, width, height)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -77,7 +77,7 @@ func BenchmarkDecodeYUY2(b *testing.B) {
 		b.Run(fmt.Sprintf("%dx%d", sz.width, sz.height), func(b *testing.B) {
 			input := make([]byte, sz.width*sz.height*2)
 			for i := 0; i < b.N; i++ {
-				_, _, err := decodeYUY2(input, sz.width, sz.height)
+				_, err := decodeYUY2(input, sz.width, sz.height)
 				if err != nil {
 					b.Fatal(err)
 				}
--- a/pkg/io/audio/audio.go
+++ b/pkg/io/audio/audio.go
@@ -5,22 +5,13 @@ import (
 )

 type Reader interface {
-	// Read reads data from the source. The caller is responsible to release the memory that's associated
-	// with data by calling the given release function. When err is not nil, the caller MUST NOT call release
-	// as data is going to be nil (no memory was given). Otherwise, the caller SHOULD call release after
-	// using the data. The caller is NOT REQUIRED to call release, as this is only a part of memory management
-	// optimization. If release is not called, the source is forced to allocate a new memory, which also means
-	// there will be new allocations during streaming, and old unused memory will become garbage. As a consequence,
-	// these garbage will put a lot of pressure to the garbage collector and makes it to run more often and finish
-	// slower as the heap memory usage increases and more garbage to collect.
-	Read() (chunk wave.Audio, release func(), err error)
+	Read() (wave.Audio, error)
 }

-type ReaderFunc func() (chunk wave.Audio, release func(), err error)
+type ReaderFunc func() (wave.Audio, error)

-func (rf ReaderFunc) Read() (chunk wave.Audio, release func(), err error) {
-	chunk, release, err = rf()
-	return
+func (rf ReaderFunc) Read() (wave.Audio, error) {
+	return rf()
 }

 // TransformFunc produces a new Reader that will produces a transformed audio
--- a/pkg/io/audio/broadcast.go
+++ b/pkg/io/audio/broadcast.go
@@ -1,76 +0,0 @@
-package audio
-
-import (
-	"errors"
-
-	"github.com/pion/mediadevices/pkg/io"
-	"github.com/pion/mediadevices/pkg/wave"
-)
-
-var errEmptySource = errors.New("Source can't be nil")
-
-// Broadcaster is a specialized video broadcaster.
-type Broadcaster struct {
-	ioBroadcaster *io.Broadcaster
-}
-
-type BroadcasterConfig struct {
-	Core *io.BroadcasterConfig
-}
-
-// NewBroadcaster creates a new broadcaster. Source is expected to drop chunks
-// when any of the readers is slower than the source.
-func NewBroadcaster(source Reader, config *BroadcasterConfig) *Broadcaster {
-	var coreConfig *io.BroadcasterConfig
-
-	if config != nil {
-		coreConfig = config.Core
-	}
-
-	broadcaster := io.NewBroadcaster(io.ReaderFunc(func() (interface{}, func(), error) {
-		return source.Read()
-	}), coreConfig)
-
-	return &Broadcaster{broadcaster}
-}
-
-// NewReader creates a new reader. Each reader will retrieve the same data from the source.
-// copyFn is used to copy the data from the source to individual readers. Broadcaster uses a small ring
-// buffer, this means that slow readers might miss some data if they're really late and the data is no longer
-// in the ring buffer.
-func (broadcaster *Broadcaster) NewReader(copyChunk bool) Reader {
-	copyFn := func(src interface{}) interface{} { return src }
-
-	if copyChunk {
-		buffer := wave.NewBuffer()
-		copyFn = func(src interface{}) interface{} {
-			realSrc, _ := src.(wave.Audio)
-			buffer.StoreCopy(realSrc)
-			return buffer.Load()
-		}
-	}
-
-	reader := broadcaster.ioBroadcaster.NewReader(copyFn)
-	return ReaderFunc(func() (wave.Audio, func(), error) {
-		data, _, err := reader.Read()
-		chunk, _ := data.(wave.Audio)
-		return chunk, func() {}, err
-	})
-}
-
-// ReplaceSource replaces the underlying source. This operation is thread safe.
-func (broadcaster *Broadcaster) ReplaceSource(source Reader) error {
-	return broadcaster.ioBroadcaster.ReplaceSource(io.ReaderFunc(func() (interface{}, func(), error) {
-		return source.Read()
-	}))
-}
-
-// Source retrieves the underlying source. This operation is thread safe.
-func (broadcaster *Broadcaster) Source() Reader {
-	source := broadcaster.ioBroadcaster.Source()
-	return ReaderFunc(func() (wave.Audio, func(), error) {
-		data, _, err := source.Read()
-		img, _ := data.(wave.Audio)
-		return img, func() {}, err
-	})
-}
--- a/pkg/io/audio/broadcast_test.go
+++ b/pkg/io/audio/broadcast_test.go
@@ -1,54 +0,0 @@
-package audio
-
-import (
-	"reflect"
-	"testing"
-
-	"github.com/pion/mediadevices/pkg/wave"
-)
-
-func TestBroadcast(t *testing.T) {
-	chunk := wave.NewFloat32Interleaved(wave.ChunkInfo{
-		Len:          8,
-		Channels:     2,
-		SamplingRate: 48000,
-	})
-
-	source := ReaderFunc(func() (wave.Audio, func(), error) {
-		return chunk, func() {}, nil
-	})
-
-	broadcaster := NewBroadcaster(source, nil)
-	readerWithoutCopy1 := broadcaster.NewReader(false)
-	readerWithoutCopy2 := broadcaster.NewReader(false)
-	actualWithoutCopy1, _, err := readerWithoutCopy1.Read()
-	if err != nil {
-		t.Fatal(err)
-	}
-	actualWithoutCopy2, _, err := readerWithoutCopy2.Read()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if &actualWithoutCopy1.(*wave.Float32Interleaved).Data[0] != &actualWithoutCopy2.(*wave.Float32Interleaved).Data[0] {
-		t.Fatal("Expected underlying buffer for frame with copy to be the same from broadcaster's buffer")
-	}
-
-	if !reflect.DeepEqual(chunk, actualWithoutCopy1) {
-		t.Fatal("Expected actual frame without copy to be the same with the original")
-	}
-
-	readerWithCopy := broadcaster.NewReader(true)
-	actualWithCopy, _, err := readerWithCopy.Read()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if &actualWithCopy.(*wave.Float32Interleaved).Data[0] == &actualWithoutCopy1.(*wave.Float32Interleaved).Data[0] {
-		t.Fatal("Expected underlying buffer for frame with copy to be different from broadcaster's buffer")
-	}
-
-	if !reflect.DeepEqual(chunk, actualWithCopy) {
-		t.Fatal("Expected actual frame without copy to be the same with the original")
-	}
-}
--- a/pkg/io/audio/buffer.go
+++ b/pkg/io/audio/buffer.go
@@ -13,15 +13,15 @@ func NewBuffer(nSamples int) TransformFunc {
 	var inBuff wave.Audio

 	return func(r Reader) Reader {
-		return ReaderFunc(func() (wave.Audio, func(), error) {
+		return ReaderFunc(func() (wave.Audio, error) {
 			for {
 				if inBuff != nil && inBuff.ChunkInfo().Len >= nSamples {
 					break
 				}

-				buff, _, err := r.Read()
+				buff, err := r.Read()
 				if err != nil {
-					return nil, func() {}, err
+					return nil, err
 				}
 				switch b := buff.(type) {
 				case *wave.Float32Interleaved:
@@ -59,7 +59,7 @@ func NewBuffer(nSamples int) TransformFunc {
 					ib.Size.Len += b.Size.Len

 				default:
-					return nil, func() {}, errUnsupported
+					return nil, errUnsupported
 				}
 			}
 			switch ib := inBuff.(type) {
@@ -71,7 +71,7 @@ func NewBuffer(nSamples int) TransformFunc {
 				copy(ibCopy.Data, ib.Data)
 				ib.Data = ib.Data[n:]
 				ib.Size.Len -= nSamples
-				return &ibCopy, func() {}, nil
+				return &ibCopy, nil

 			case *wave.Float32Interleaved:
 				ibCopy := *ib
@@ -81,9 +81,9 @@ func NewBuffer(nSamples int) TransformFunc {
 				copy(ibCopy.Data, ib.Data)
 				ib.Data = ib.Data[n:]
 				ib.Size.Len -= nSamples
-				return &ibCopy, func() {}, nil
+				return &ibCopy, nil
 			}
-			return nil, func() {}, errUnsupported
+			return nil, errUnsupported
 		})
 	}
 }
--- a/pkg/io/audio/buffer_test.go
+++ b/pkg/io/audio/buffer_test.go
@@ -49,16 +49,16 @@ func TestBuffer(t *testing.T) {
 	trans := NewBuffer(3)

 	var iSent int
-	r := trans(ReaderFunc(func() (wave.Audio, func(), error) {
+	r := trans(ReaderFunc(func() (wave.Audio, error) {
 		if iSent < len(input) {
 			iSent++
-			return input[iSent-1], func() {}, nil
+			return input[iSent-1], nil
 		}
-		return nil, func() {}, io.EOF
+		return nil, io.EOF
 	}))

 	for i := 0; ; i++ {
-		a, _, err := r.Read()
+		a, err := r.Read()
 		if err != nil {
 			if err == io.EOF && i >= len(expected) {
 				break
--- a/pkg/io/audio/detect.go
+++ b/pkg/io/audio/detect.go
@@ -1,55 +0,0 @@
-package audio
-
-import (
-	"time"
-
-	"github.com/pion/mediadevices/pkg/prop"
-	"github.com/pion/mediadevices/pkg/wave"
-)
-
-// DetectChanges will detect chunk and audio property changes. For audio property detection,
-// since it's time related, interval will be used to determine the sample rate.
-func DetectChanges(interval time.Duration, onChange func(prop.Media)) TransformFunc {
-	return func(r Reader) Reader {
-		var currentProp prop.Media
-		var chunkCount uint
-		return ReaderFunc(func() (wave.Audio, func(), error) {
-			var dirty bool
-
-			chunk, _, err := r.Read()
-			if err != nil {
-				return nil, func() {}, err
-			}
-
-			info := chunk.ChunkInfo()
-			if currentProp.ChannelCount != info.Channels {
-				currentProp.ChannelCount = info.Channels
-				dirty = true
-			}
-
-			if currentProp.SampleRate != info.SamplingRate {
-				currentProp.SampleRate = info.SamplingRate
-				dirty = true
-			}
-
-			var latency time.Duration
-			if currentProp.SampleRate != 0 {
-				latency = time.Duration(chunk.ChunkInfo().Len) * time.Second / time.Nanosecond / time.Duration(currentProp.SampleRate)
-			}
-			if currentProp.Latency != latency {
-				currentProp.Latency = latency
-				dirty = true
-			}
-
-			// TODO: Also detect sample format changes?
-			// TODO: Add audio detect changes. As of now, there's no useful property to track.
-
-			if dirty {
-				onChange(currentProp)
-			}
-
-			chunkCount++
-			return chunk, func() {}, nil
-		})
-	}
-}
--- a/pkg/io/audio/detect_test.go
+++ b/pkg/io/audio/detect_test.go
@@ -1,76 +0,0 @@
-package audio
-
-import (
-	"reflect"
-	"testing"
-	"time"
-
-	"github.com/pion/mediadevices/pkg/prop"
-	"github.com/pion/mediadevices/pkg/wave"
-)
-
-func TestDetectChanges(t *testing.T) {
-	buildSource := func(p prop.Media) (Reader, func(prop.Media)) {
-		return ReaderFunc(func() (wave.Audio, func(), error) {
-				return wave.NewFloat32Interleaved(wave.ChunkInfo{
-					Len:          960,
-					Channels:     p.ChannelCount,
-					SamplingRate: p.SampleRate,
-				}), func() {}, nil
-			}), func(newProp prop.Media) {
-				p = newProp
-			}
-	}
-
-	t.Run("OnChangeCalledBeforeFirstFrame", func(t *testing.T) {
-		var detectBeforeFirstChunk bool
-		var expected prop.Media
-		var actual prop.Media
-		expected.ChannelCount = 2
-		expected.SampleRate = 48000
-		expected.Latency = time.Millisecond * 20
-		src, _ := buildSource(expected)
-		src = DetectChanges(time.Second, func(p prop.Media) {
-			actual = p
-			detectBeforeFirstChunk = true
-		})(src)
-
-		_, _, err := src.Read()
-		if err != nil {
-			t.Fatal(err)
-		}
-
-		if !detectBeforeFirstChunk {
-			t.Fatal("on change callback should have called before first chunk")
-		}
-
-		if !reflect.DeepEqual(actual, expected) {
-			t.Fatalf("Received an unexpected prop\nExpected:\n%v\nActual:\n%v\n", expected, actual)
-		}
-	})
-
-	t.Run("DetectChangesOnEveryUpdate", func(t *testing.T) {
-		var expected prop.Media
-		var actual prop.Media
-		expected.ChannelCount = 2
-		expected.SampleRate = 48000
-		expected.Latency = 20 * time.Millisecond
-		src, update := buildSource(expected)
-		src = DetectChanges(time.Second, func(p prop.Media) {
-			actual = p
-		})(src)
-
-		for channelCount := 1; channelCount < 8; channelCount++ {
-			expected.ChannelCount = channelCount
-			update(expected)
-			_, _, err := src.Read()
-			if err != nil {
-				t.Fatal(err)
-			}
-
-			if !reflect.DeepEqual(actual, expected) {
-				t.Fatalf("Received an unexpected prop\nExpected:\n%v\nActual:\n%v\n", expected, actual)
-			}
-		}
-	})
-}
--- a/pkg/io/audio/mixer.go
+++ b/pkg/io/audio/mixer.go
@@ -8,14 +8,14 @@ import (
 // NewChannelMixer creates audio transform to mix audio channels.
 func NewChannelMixer(channels int, mixer mixer.ChannelMixer) TransformFunc {
 	return func(r Reader) Reader {
-		return ReaderFunc(func() (wave.Audio, func(), error) {
-			buff, _, err := r.Read()
+		return ReaderFunc(func() (wave.Audio, error) {
+			buff, err := r.Read()
 			if err != nil {
-				return nil, func() {}, err
+				return nil, err
 			}
 			ci := buff.ChunkInfo()
 			if ci.Channels == channels {
-				return buff, func() {}, nil
+				return buff, nil
 			}

 			ci.Channels = channels
@@ -32,9 +32,9 @@ func NewChannelMixer(channels int, mixer mixer.ChannelMixer) TransformFunc {
 				mixed = wave.NewFloat32NonInterleaved(ci)
 			}
 			if err := mixer.Mix(mixed, buff); err != nil {
-				return nil, func() {}, err
+				return nil, err
 			}
-			return mixed, func() {}, nil
+			return mixed, nil
 		})
 	}
 }
--- a/pkg/io/audio/mixer_test.go
+++ b/pkg/io/audio/mixer_test.go
@@ -34,16 +34,16 @@ func TestMixer(t *testing.T) {
 	trans := NewChannelMixer(1, &mixer.MonoMixer{})

 	var iSent int
-	r := trans(ReaderFunc(func() (wave.Audio, func(), error) {
+	r := trans(ReaderFunc(func() (wave.Audio, error) {
 		if iSent < len(input) {
 			iSent++
-			return input[iSent-1], func() {}, nil
+			return input[iSent-1], nil
 		}
-		return nil, func() {}, io.EOF
+		return nil, io.EOF
 	}))

 	for i := 0; ; i++ {
-		a, _, err := r.Read()
+		a, err := r.Read()
 		if err != nil {
 			if err == io.EOF && i >= len(expected) {
 				break
--- a/pkg/io/broadcast.go
+++ b/pkg/io/broadcast.go
@@ -1,162 +0,0 @@
-package io
-
-import (
-	"fmt"
-	"sync/atomic"
-	"time"
-)
-
-const (
-	maskReading                = 1 << 63
-	defaultBroadcasterRingSize = 32
-	// TODO: If the data source has fps greater than 30, they'll see some
-	// 			 fps fluctuation. But, 30 fps should be enough for general cases.
-	defaultBroadcasterRingPollDuration = time.Millisecond * 33
-)
-
-var errEmptySource = fmt.Errorf("Source can't be nil")
-
-type broadcasterData struct {
-	data  interface{}
-	count uint32
-	err   error
-}
-
-type broadcasterRing struct {
-	// reading (1 bit) + reserved (31 bits) + data count (32 bits)
-	// IMPORTANT: state has to be the first element in struct, otherwise LoadUint64 will panic in 32 bits systems
-	//            due to unallignment
-	state        uint64
-	buffer       []atomic.Value
-	pollDuration time.Duration
-}
-
-func newBroadcasterRing(size uint, pollDuration time.Duration) *broadcasterRing {
-	return &broadcasterRing{buffer: make([]atomic.Value, size), pollDuration: pollDuration}
-}
-
-func (ring *broadcasterRing) index(count uint32) int {
-	return int(count) % len(ring.buffer)
-}
-
-func (ring *broadcasterRing) acquire(count uint32) func(*broadcasterData) {
-	// Reader has reached the latest data, should read from the source.
-	// Only allow 1 reader to read from the source. When there are more than 1 readers,
-	// the other readers will need to share the same data that the first reader gets from
-	// the source.
-	state := uint64(count)
-	if atomic.CompareAndSwapUint64(&ring.state, state, state|maskReading) {
-		return func(data *broadcasterData) {
-			i := ring.index(count)
-			ring.buffer[i].Store(data)
-			atomic.StoreUint64(&ring.state, uint64(count+1))
-		}
-	}
-
-	return nil
-}
-
-func (ring *broadcasterRing) get(count uint32) *broadcasterData {
-	for {
-		reading := uint64(count) | maskReading
-		// TODO: since it's lockless, it spends a lot of resources in the scheduling.
-		for atomic.LoadUint64(&ring.state) == reading {
-			// Yield current goroutine to let other goroutines to run instead
-			time.Sleep(ring.pollDuration)
-		}
-
-		i := ring.index(count)
-		data := ring.buffer[i].Load().(*broadcasterData)
-		if data.count == count {
-			return data
-		}
-
-		count++
-	}
-}
-
-func (ring *broadcasterRing) lastCount() uint32 {
-	// ring.state always keeps track the next count, so we need to subtract it by 1 to get the
-	// last count
-	return uint32(atomic.LoadUint64(&ring.state)) - 1
-}
-
-// Broadcaster is a generic pull-based broadcaster. Broadcaster is unique in a sense that
-// readers can come and go at anytime, and readers don't need to close or notify broadcaster.
-type Broadcaster struct {
-	source atomic.Value
-	buffer *broadcasterRing
-}
-
-// BroadcasterConfig is a config to control broadcaster behaviour
-type BroadcasterConfig struct {
-	// BufferSize configures the underlying ring buffer size that's being used
-	// to avoid data lost for late readers. The default value is 32.
-	BufferSize uint
-	// PollDuration configures the sleep duration in waiting for new data to come.
-	// The default value is 33 ms.
-	PollDuration time.Duration
-}
-
-// NewBroadcaster creates a new broadcaster. Source is expected to drop frames
-// when any of the readers is slower than the source.
-func NewBroadcaster(source Reader, config *BroadcasterConfig) *Broadcaster {
-	pollDuration := defaultBroadcasterRingPollDuration
-	var bufferSize uint = defaultBroadcasterRingSize
-	if config != nil {
-		if config.PollDuration != 0 {
-			pollDuration = config.PollDuration
-		}
-
-		if config.BufferSize != 0 {
-			bufferSize = config.BufferSize
-		}
-	}
-
-	var broadcaster Broadcaster
-	broadcaster.buffer = newBroadcasterRing(bufferSize, pollDuration)
-	broadcaster.ReplaceSource(source)
-
-	return &broadcaster
-}
-
-// NewReader creates a new reader. Each reader will retrieve the same data from the source.
-// copyFn is used to copy the data from the source to individual readers. Broadcaster uses a small ring
-// buffer, this means that slow readers might miss some data if they're really late and the data is no longer
-// in the ring buffer.
-func (broadcaster *Broadcaster) NewReader(copyFn func(interface{}) interface{}) Reader {
-	currentCount := broadcaster.buffer.lastCount()
-
-	return ReaderFunc(func() (data interface{}, release func(), err error) {
-		currentCount++
-		if push := broadcaster.buffer.acquire(currentCount); push != nil {
-			data, _, err = broadcaster.source.Load().(Reader).Read()
-			push(&broadcasterData{
-				data:  data,
-				err:   err,
-				count: currentCount,
-			})
-		} else {
-			ringData := broadcaster.buffer.get(currentCount)
-			data, err, currentCount = ringData.data, ringData.err, ringData.count
-		}
-
-		data = copyFn(data)
-		return
-	})
-}
-
-// ReplaceSource replaces the underlying source. This operation is thread safe.
-func (broadcaster *Broadcaster) ReplaceSource(source Reader) error {
-	if source == nil {
-		return errEmptySource
-	}
-
-	broadcaster.source.Store(source)
-	return nil
-}
-
-// ReplaceSource retrieves the underlying source. This operation is thread safe.
-func (broadcaster *Broadcaster) Source() Reader {
-	return broadcaster.source.Load().(Reader)
-}
--- a/pkg/io/broadcast_test.go
+++ b/pkg/io/broadcast_test.go
@@ -1,148 +0,0 @@
-package io
-
-import (
-	"fmt"
-	"runtime"
-	"sync"
-	"sync/atomic"
-	"testing"
-	"time"
-)
-
-func TestBroadcast(t *testing.T) {
-	// https://github.com/pion/mediadevices/issues/198
-	if runtime.GOOS == "darwin" {
-		t.Skip("Skipping because Darwin CI is not reliable for timing related tests.")
-	}
-	frames := make([]int, 5*30) // 5 seconds worth of frames
-	for i := range frames {
-		frames[i] = i
-	}
-
-	routinePauseConds := []struct {
-		src          bool
-		dst          bool
-		expectedFPS  float64
-		expectedDrop float64
-	}{
-		{
-			src:         false,
-			dst:         false,
-			expectedFPS: 30,
-		},
-		{
-			src:          true,
-			dst:          false,
-			expectedFPS:  20,
-			expectedDrop: 10,
-		},
-		{
-			src:          false,
-			dst:          true,
-			expectedFPS:  20,
-			expectedDrop: 10,
-		},
-	}
-
-	for _, pauseCond := range routinePauseConds {
-		pauseCond := pauseCond
-		t.Run(fmt.Sprintf("SrcPause-%v/DstPause-%v", pauseCond.src, pauseCond.dst), func(t *testing.T) {
-			for n := 1; n <= 256; n *= 16 {
-				n := n
-
-				t.Run(fmt.Sprintf("Readers-%d", n), func(t *testing.T) {
-					var src Reader
-					interval := time.NewTicker(time.Millisecond * 33) // 30 fps
-					defer interval.Stop()
-					frameCount := 0
-					frameSent := 0
-					lastSend := time.Now()
-					src = ReaderFunc(func() (interface{}, func(), error) {
-						if pauseCond.src && frameSent == 30 {
-							time.Sleep(time.Second)
-						}
-						<-interval.C
-
-						now := time.Now()
-						if interval := now.Sub(lastSend); interval > time.Millisecond*33*3/2 {
-							// Source reader should drop frames to catch up the latest frame.
-							drop := int(interval/(time.Millisecond*33)) - 1
-							frameCount += drop
-							t.Logf("Skipped %d frames", drop)
-						}
-						lastSend = now
-						frame := frames[frameCount]
-						frameCount++
-						frameSent++
-						return frame, func() {}, nil
-					})
-					broadcaster := NewBroadcaster(src, nil)
-					var done uint32
-					duration := time.Second * 3
-					fpsChan := make(chan []float64)
-
-					var wg sync.WaitGroup
-					wg.Add(n)
-					for i := 0; i < n; i++ {
-						go func() {
-							reader := broadcaster.NewReader(func(src interface{}) interface{} { return src })
-							count := 0
-							lastFrameCount := -1
-							droppedFrames := 0
-							wg.Done()
-							wg.Wait()
-							for atomic.LoadUint32(&done) == 0 {
-								if pauseCond.dst && count == 30 {
-									time.Sleep(time.Second)
-								}
-								frame, _, err := reader.Read()
-								if err != nil {
-									t.Error(err)
-								}
-								frameCount := frame.(int)
-								droppedFrames += (frameCount - lastFrameCount - 1)
-								lastFrameCount = frameCount
-								count++
-							}
-
-							fps := float64(count) / duration.Seconds()
-							if fps < pauseCond.expectedFPS-2 || fps > pauseCond.expectedFPS+2 {
-								t.Fatal("Unexpected average FPS")
-							}
-
-							droppedFramesPerSecond := float64(droppedFrames) / duration.Seconds()
-							if droppedFramesPerSecond < pauseCond.expectedDrop-2 || droppedFramesPerSecond > pauseCond.expectedDrop+2 {
-								t.Fatal("Unexpected drop count")
-							}
-
-							fpsChan <- []float64{fps, droppedFramesPerSecond, float64(lastFrameCount)}
-						}()
-					}
-
-					time.Sleep(duration)
-					atomic.StoreUint32(&done, 1)
-
-					var fpsAvg float64
-					var droppedFramesPerSecondAvg float64
-					var lastFrameCountAvg float64
-					var count int
-					for metric := range fpsChan {
-						fps, droppedFramesPerSecond, lastFrameCount := metric[0], metric[1], metric[2]
-						fpsAvg += fps
-						droppedFramesPerSecondAvg += droppedFramesPerSecond
-						lastFrameCountAvg += lastFrameCount
-						count++
-						if count == n {
-							break
-						}
-					}
-
-					t.Log("Average FPS                      :", fpsAvg/float64(n))
-					t.Log("Average dropped frames per second:", droppedFramesPerSecondAvg/float64(n))
-					t.Log("Last frame count (src)           :", frameCount)
-					t.Log("Average last frame count (dst)   :", lastFrameCountAvg/float64(n))
-				})
-			}
-		})
-	}
-}
--- a/pkg/io/io.go
+++ b/pkg/io/io.go
@@ -0,0 +1,11 @@
+package io
+
+// Copy copies data from src to dst. If dst is not big enough, return an
+// InsufficientBufferError.
+func Copy(dst, src []byte) (n int, err error) {
+	if len(dst) < len(src) {
+		return 0, &InsufficientBufferError{len(src)}
+	}
+
+	return copy(dst, src), nil
+}
--- a/pkg/io/io_test.go
+++ b/pkg/io/io_test.go
@@ -0,0 +1,45 @@
+package io
+
+import (
+	"log"
+	"testing"
+)
+
+func TestCopy(t *testing.T) {
+	var dst []byte
+	src := make([]byte, 4)
+
+	n, err := Copy(dst, src)
+	if err == nil {
+		t.Fatal("expected err to be non-nill")
+	}
+
+	if n != 0 {
+		t.Fatalf("expected n to be 0, but got %d", n)
+	}
+
+	e, ok := err.(*InsufficientBufferError)
+	if !ok {
+		t.Fatalf("expected error to be InsufficientBufferError")
+	}
+
+	if e.RequiredSize != len(src) {
+		t.Fatalf("expected required size to be %d, but got %d", len(src), e.RequiredSize)
+	}
+
+	dst = make([]byte, 2*e.RequiredSize)
+	n, err = Copy(dst, src)
+	if err != nil {
+		t.Fatalf("expected to not get an error after expanding the buffer")
+	}
+
+	if n != len(src) {
+		t.Fatalf("expected n to be %d, but got %d", len(src), n)
+	}
+
+	for i := 0; i < len(src); i++ {
+		if src[i] != dst[i] {
+			log.Fatalf("expected value at %d to be %d, but got %d", i, src[i], dst[i])
+		}
+	}
+}
--- a/pkg/io/reader.go
+++ b/pkg/io/reader.go
@@ -1,23 +1,14 @@
 package io

-// Reader is a generic data reader. In the future, interface{} should be replaced by a generic type
-// to provide strong type.
+// Reader is a generic reader. When generic is ready, interface{} will be replaced
+// with a generic type and will provide type safety.
 type Reader interface {
-	// Read reads data from the source. The caller is responsible to release the memory that's associated
-	// with data by calling the given release function. When err is not nil, the caller MUST NOT call release
-	// as data is going to be nil (no memory was given). Otherwise, the caller SHOULD call release after
-	// using the data. The caller is NOT REQUIRED to call release, as this is only a part of memory management
-	// optimization. If release is not called, the source is forced to allocate a new memory, which also means
-	// there will be new allocations during streaming, and old unused memory will become garbage. As a consequence,
-	// these garbage will put a lot of pressure to the garbage collector and makes it to run more often and finish
-	// slower as the heap memory usage increases and more garbage to collect.
-	Read() (data interface{}, release func(), err error)
+	Read() (interface{}, error)
 }

-// ReaderFunc is a proxy type for Reader
-type ReaderFunc func() (data interface{}, release func(), err error)
+// ReaderFunc is a proxy type to make easier for users to implement Reader
+type ReaderFunc func() (interface{}, error)

-func (f ReaderFunc) Read() (data interface{}, release func(), err error) {
-	data, release, err = f()
-	return
+func (f ReaderFunc) Read() (interface{}, error) {
+	return f()
 }
--- a/pkg/io/video/broadcast.go
+++ b/pkg/io/video/broadcast.go
@@ -1,76 +0,0 @@
-package video
-
-import (
-	"fmt"
-	"image"
-
-	"github.com/pion/mediadevices/pkg/io"
-)
-
-var errEmptySource = fmt.Errorf("Source can't be nil")
-
-// Broadcaster is a specialized video broadcaster.
-type Broadcaster struct {
-	ioBroadcaster *io.Broadcaster
-}
-
-type BroadcasterConfig struct {
-	Core *io.BroadcasterConfig
-}
-
-// NewBroadcaster creates a new broadcaster. Source is expected to drop frames
-// when any of the readers is slower than the source.
-func NewBroadcaster(source Reader, config *BroadcasterConfig) *Broadcaster {
-	var coreConfig *io.BroadcasterConfig
-
-	if config != nil {
-		coreConfig = config.Core
-	}
-
-	broadcaster := io.NewBroadcaster(io.ReaderFunc(func() (interface{}, func(), error) {
-		return source.Read()
-	}), coreConfig)
-
-	return &Broadcaster{broadcaster}
-}
-
-// NewReader creates a new reader. Each reader will retrieve the same data from the source.
-// copyFn is used to copy the data from the source to individual readers. Broadcaster uses a small ring
-// buffer, this means that slow readers might miss some data if they're really late and the data is no longer
-// in the ring buffer.
-func (broadcaster *Broadcaster) NewReader(copyFrame bool) Reader {
-	copyFn := func(src interface{}) interface{} { return src }
-
-	if copyFrame {
-		buffer := NewFrameBuffer(0)
-		copyFn = func(src interface{}) interface{} {
-			realSrc, _ := src.(image.Image)
-			buffer.StoreCopy(realSrc)
-			return buffer.Load()
-		}
-	}
-
-	reader := broadcaster.ioBroadcaster.NewReader(copyFn)
-	return ReaderFunc(func() (image.Image, func(), error) {
-		data, _, err := reader.Read()
-		img, _ := data.(image.Image)
-		return img, func() {}, err
-	})
-}
-
-// ReplaceSource replaces the underlying source. This operation is thread safe.
-func (broadcaster *Broadcaster) ReplaceSource(source Reader) error {
-	return broadcaster.ioBroadcaster.ReplaceSource(io.ReaderFunc(func() (interface{}, func(), error) {
-		return source.Read()
-	}))
-}
-
-// Source retrieves the underlying source. This operation is thread safe.
-func (broadcaster *Broadcaster) Source() Reader {
-	source := broadcaster.ioBroadcaster.Source()
-	return ReaderFunc(func() (image.Image, func(), error) {
-		data, _, err := source.Read()
-		img, _ := data.(image.Image)
-		return img, func() {}, err
-	})
-}
--- a/pkg/io/video/broadcast_test.go
+++ b/pkg/io/video/broadcast_test.go
@@ -1,49 +0,0 @@
-package video
-
-import (
-	"image"
-	"reflect"
-	"testing"
-)
-
-func TestBroadcast(t *testing.T) {
-	resolution := image.Rect(0, 0, 1920, 1080)
-	img := image.NewGray(resolution)
-	source := ReaderFunc(func() (image.Image, func(), error) {
-		return img, func() {}, nil
-	})
-
-	broadcaster := NewBroadcaster(source, nil)
-	readerWithoutCopy1 := broadcaster.NewReader(false)
-	readerWithoutCopy2 := broadcaster.NewReader(false)
-	actualWithoutCopy1, _, err := readerWithoutCopy1.Read()
-	if err != nil {
-		t.Fatal(err)
-	}
-	actualWithoutCopy2, _, err := readerWithoutCopy2.Read()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if &actualWithoutCopy1.(*image.Gray).Pix[0] != &actualWithoutCopy2.(*image.Gray).Pix[0] {
-		t.Fatal("Expected underlying buffer for frame with copy to be the same from broadcaster's buffer")
-	}
-
-	if !reflect.DeepEqual(img, actualWithoutCopy1) {
-		t.Fatal("Expected actual frame without copy to be the same with the original")
-	}
-
-	readerWithCopy := broadcaster.NewReader(true)
-	actualWithCopy, _, err := readerWithCopy.Read()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if &actualWithCopy.(*image.Gray).Pix[0] == &actualWithoutCopy1.(*image.Gray).Pix[0] {
-		t.Fatal("Expected underlying buffer for frame with copy to be different from broadcaster's buffer")
-	}
-
-	if !reflect.DeepEqual(img, actualWithCopy) {
-		t.Fatal("Expected actual frame without copy to be the same with the original")
-	}
-}
--- a/pkg/io/video/convert.go
+++ b/pkg/io/video/convert.go
@@ -63,10 +63,10 @@ func imageToYCbCr(dst *image.YCbCr, src image.Image) {
 // ToI420 converts r to a new reader that will output images in I420 format
 func ToI420(r Reader) Reader {
 	var yuvImg image.YCbCr
-	return ReaderFunc(func() (image.Image, func(), error) {
-		img, _, err := r.Read()
+	return ReaderFunc(func() (image.Image, error) {
+		img, err := r.Read()
 		if err != nil {
-			return nil, func() {}, err
+			return nil, err
 		}

 		imageToYCbCr(&yuvImg, img)
@@ -79,11 +79,11 @@ func ToI420(r Reader) Reader {
 			i422ToI420(&yuvImg)
 		case image.YCbCrSubsampleRatio420:
 		default:
-			return nil, func() {}, fmt.Errorf("unsupported pixel format: %s", yuvImg.SubsampleRatio)
+			return nil, fmt.Errorf("unsupported pixel format: %s", yuvImg.SubsampleRatio)
 		}

 		yuvImg.SubsampleRatio = image.YCbCrSubsampleRatio420
-		return &yuvImg, func() {}, nil
+		return &yuvImg, nil
 	})
 }

@@ -130,13 +130,13 @@ func imageToRGBA(dst *image.RGBA, src image.Image) {
 // ToRGBA converts r to a new reader that will output images in RGBA format
 func ToRGBA(r Reader) Reader {
 	var dst image.RGBA
-	return ReaderFunc(func() (image.Image, func(), error) {
-		img, _, err := r.Read()
+	return ReaderFunc(func() (image.Image, error) {
+		img, err := r.Read()
 		if err != nil {
-			return nil, func() {}, err
+			return nil, err
 		}

 		imageToRGBA(&dst, img)
-		return &dst, func() {}, nil
+		return &dst, nil
 	})
 }
--- a/pkg/io/video/convert_test.go
+++ b/pkg/io/video/convert_test.go
@@ -144,10 +144,10 @@ func TestToI420(t *testing.T) {
 	for name, c := range cases {
 		c := c
 		t.Run(name, func(t *testing.T) {
-			r := ToI420(ReaderFunc(func() (image.Image, func(), error) {
-				return c.src, func() {}, nil
+			r := ToI420(ReaderFunc(func() (image.Image, error) {
+				return c.src, nil
 			}))
-			out, _, err := r.Read()
+			out, err := r.Read()
 			if err != nil {
 				t.Fatalf("Unexpected error: %v", err)
 			}
@@ -199,10 +199,10 @@ func TestToRGBA(t *testing.T) {
 	for name, c := range cases {
 		c := c
 		t.Run(name, func(t *testing.T) {
-			r := ToRGBA(ReaderFunc(func() (image.Image, func(), error) {
-				return c.src, func() {}, nil
+			r := ToRGBA(ReaderFunc(func() (image.Image, error) {
+				return c.src, nil
 			}))
-			out, _, err := r.Read()
+			out, err := r.Read()
 			if err != nil {
 				t.Fatalf("Unexpected error: %v", err)
 			}
@@ -225,12 +225,12 @@ func BenchmarkToI420(b *testing.B) {
 			for name, img := range cases {
 				img := img
 				b.Run(name, func(b *testing.B) {
-					r := ToI420(ReaderFunc(func() (image.Image, func(), error) {
-						return img, func() {}, nil
+					r := ToI420(ReaderFunc(func() (image.Image, error) {
+						return img, nil
 					}))

 					for i := 0; i < b.N; i++ {
-						_, _, err := r.Read()
+						_, err := r.Read()
 						if err != nil {
 							b.Fatalf("Unexpected error: %v", err)
 						}
@@ -253,12 +253,12 @@ func BenchmarkToRGBA(b *testing.B) {
 			for name, img := range cases {
 				img := img
 				b.Run(name, func(b *testing.B) {
-					r := ToRGBA(ReaderFunc(func() (image.Image, func(), error) {
-						return img, func() {}, nil
+					r := ToRGBA(ReaderFunc(func() (image.Image, error) {
+						return img, nil
 					}))

 					for i := 0; i < b.N; i++ {
-						_, _, err := r.Read()
+						_, err := r.Read()
 						if err != nil {
 							b.Fatalf("Unexpected error: %v", err)
 						}
--- a/pkg/io/video/detect.go
+++ b/pkg/io/video/detect.go
@@ -14,12 +14,12 @@ func DetectChanges(interval time.Duration, onChange func(prop.Media)) TransformF
 		var currentProp prop.Media
 		var lastTaken time.Time
 		var frames uint
-		return ReaderFunc(func() (image.Image, func(), error) {
+		return ReaderFunc(func() (image.Image, error) {
 			var dirty bool

-			img, _, err := r.Read()
+			img, err := r.Read()
 			if err != nil {
-				return nil, func() {}, err
+				return nil, err
 			}

 			bounds := img.Bounds()
@@ -52,7 +52,7 @@ func DetectChanges(interval time.Duration, onChange func(prop.Media)) TransformF
 			}

 			frames++
-			return img, func() {}, nil
+			return img, nil
 		})
 	}
 }
--- a/pkg/io/video/detect_test.go
+++ b/pkg/io/video/detect_test.go
@@ -12,8 +12,8 @@ import (

 func BenchmarkDetectChanges(b *testing.B) {
 	var src Reader
-	src = ReaderFunc(func() (image.Image, func(), error) {
-		return image.NewRGBA(image.Rect(0, 0, 1920, 1080)), func() {}, nil
+	src = ReaderFunc(func() (image.Image, error) {
+		return image.NewRGBA(image.Rect(0, 0, 1920, 1080)), nil
 	})

 	b.Run("WithoutDetectChanges", func(b *testing.B) {
@@ -40,8 +40,8 @@ func BenchmarkDetectChanges(b *testing.B) {

 func TestDetectChanges(t *testing.T) {
 	buildSource := func(p prop.Media) (Reader, func(prop.Media)) {
-		return ReaderFunc(func() (image.Image, func(), error) {
-				return image.NewRGBA(image.Rect(0, 0, p.Width, p.Height)), func() {}, nil
+		return ReaderFunc(func() (image.Image, error) {
+				return image.NewRGBA(image.Rect(0, 0, p.Width, p.Height)), nil
 			}), func(newProp prop.Media) {
 				p = newProp
 			}
@@ -86,7 +86,7 @@ func TestDetectChanges(t *testing.T) {
 			detectBeforeFirstFrame = true
 		})(src)

-		frame, _, err := src.Read()
+		frame, err := src.Read()
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -113,7 +113,7 @@ func TestDetectChanges(t *testing.T) {
 				expected.Width = width
 				expected.Height = height
 				update(expected)
-				frame, _, err := src.Read()
+				frame, err := src.Read()
 				if err != nil {
 					t.Fatal(err)
 				}
@@ -143,7 +143,7 @@ func TestDetectChanges(t *testing.T) {
 		})(src)

 		for count < 3 {
-			frame, _, err := src.Read()
+			frame, err := src.Read()
 			if err != nil {
 				t.Fatal(err)
 			}
--- a/pkg/io/video/scale.go
+++ b/pkg/io/video/scale.go
@@ -156,10 +156,10 @@ func Scale(width, height int, scaler Scaler) TransformFunc {
 			}
 		}

-		return ReaderFunc(func() (image.Image, func(), error) {
-			img, _, err := r.Read()
+		return ReaderFunc(func() (image.Image, error) {
+			img, err := r.Read()
 			if err != nil {
-				return nil, func() {}, err
+				return nil, err
 			}

 			switch v := img.(type) {
@@ -169,7 +169,7 @@ func Scale(width, height int, scaler Scaler) TransformFunc {
 				scalerCached.Scale(dst, rect, v, v.Rect, draw.Src, nil)

 				cloned := *dst // clone metadata
-				return &cloned, func() {}, nil
+				return &cloned, nil

 			case *image.YCbCr:
 				ycbcrRealloc(v)
@@ -184,10 +184,10 @@ func Scale(width, height int, scaler Scaler) TransformFunc {
 				scalerCached.Scale(dst, dst.Bounds(), src, src.Bounds(), draw.Src, nil)

 				cloned := *(imgScaled.(*image.YCbCr)) // clone metadata
-				return &cloned, func() {}, nil
+				return &cloned, nil

 			default:
-				return nil, func() {}, errUnsupportedImageType
+				return nil, errUnsupportedImageType
 			}
 		})
 	}
--- a/pkg/io/video/scale_test.go
+++ b/pkg/io/video/scale_test.go
@@ -215,11 +215,11 @@ func TestScale(t *testing.T) {
 				c := c
 				t.Run(name, func(t *testing.T) {
 					trans := Scale(c.width, c.height, algo)
-					r := trans(ReaderFunc(func() (image.Image, func(), error) {
-						return c.src, func() {}, nil
+					r := trans(ReaderFunc(func() (image.Image, error) {
+						return c.src, nil
 					}))
 					for i := 0; i < 4; i++ {
-						out, _, err := r.Read()
+						out, err := r.Read()
 						if err != nil {
 							t.Fatalf("Unexpected error: %v", err)
 						}
@@ -261,12 +261,12 @@ func BenchmarkScale(b *testing.B) {
 						img := img
 						b.Run(name, func(b *testing.B) {
 							trans := Scale(640, 360, algo)
-							r := trans(ReaderFunc(func() (image.Image, func(), error) {
-								return img, func() {}, nil
+							r := trans(ReaderFunc(func() (image.Image, error) {
+								return img, nil
 							}))

 							for i := 0; i < b.N; i++ {
-								_, _, err := r.Read()
+								_, err := r.Read()
 								if err != nil {
 									b.Fatalf("Unexpected error: %v", err)
 								}
--- a/pkg/io/video/throttle.go
+++ b/pkg/io/video/throttle.go
@@ -10,16 +10,16 @@ import (
 func Throttle(rate float32) TransformFunc {
 	return func(r Reader) Reader {
 		ticker := time.NewTicker(time.Duration(int64(float64(time.Second) / float64(rate))))
-		return ReaderFunc(func() (image.Image, func(), error) {
+		return ReaderFunc(func() (image.Image, error) {
 			for {
-				img, _, err := r.Read()
+				img, err := r.Read()
 				if err != nil {
 					ticker.Stop()
-					return nil, func() {}, err
+					return nil, err
 				}
 				select {
 				case <-ticker.C:
-					return img, func() {}, nil
+					return img, nil
 				default:
 				}
 			}
--- a/pkg/io/video/throttle_test.go
+++ b/pkg/io/video/throttle_test.go
@@ -19,14 +19,14 @@ func TestThrottle(t *testing.T) {

 	var cntPush int
 	trans := Throttle(50)
-	r := trans(ReaderFunc(func() (image.Image, func(), error) {
+	r := trans(ReaderFunc(func() (image.Image, error) {
 		<-ticker.C
 		cntPush++
-		return img, func() {}, nil
+		return img, nil
 	}))

 	for i := 0; i < 20; i++ {
-		_, _, err := r.Read()
+		_, err := r.Read()
 		if err != nil {
 			t.Fatalf("Unexpected error: %v", err)
 		}
--- a/pkg/io/video/video.go
+++ b/pkg/io/video/video.go
@@ -5,22 +5,13 @@ import (
 )

 type Reader interface {
-	// Read reads data from the source. The caller is responsible to release the memory that's associated
-	// with data by calling the given release function. When err is not nil, the caller MUST NOT call release
-	// as data is going to be nil (no memory was given). Otherwise, the caller SHOULD call release after
-	// using the data. The caller is NOT REQUIRED to call release, as this is only a part of memory management
-	// optimization. If release is not called, the source is forced to allocate a new memory, which also means
-	// there will be new allocations during streaming, and old unused memory will become garbage. As a consequence,
-	// these garbage will put a lot of pressure to the garbage collector and makes it to run more often and finish
-	// slower as the heap memory usage increases and more garbage to collect.
-	Read() (img image.Image, release func(), err error)
+	Read() (img image.Image, err error)
 }

-type ReaderFunc func() (img image.Image, release func(), err error)
+type ReaderFunc func() (img image.Image, err error)

-func (rf ReaderFunc) Read() (img image.Image, release func(), err error) {
-	img, release, err = rf()
-	return
+func (rf ReaderFunc) Read() (img image.Image, err error) {
+	return rf()
 }

 // TransformFunc produces a new Reader that will produces a transformed video
--- a/pkg/prop/bool.go
+++ b/pkg/prop/bool.go
@@ -1,7 +1,5 @@
 package prop

-import "fmt"
-
 // BoolConstraint is an interface to represent bool value constraint.
 type BoolConstraint interface {
 	Compare(bool) (float64, bool)
@@ -22,11 +20,6 @@ func (b BoolExact) Compare(o bool) (float64, bool) {
 // Value implements BoolConstraint.
 func (b BoolExact) Value() bool { return bool(b) }

-// String implements Stringify
-func (b BoolExact) String() string {
-	return fmt.Sprintf("%t (exact)", b)
-}
-
 // Bool specifies ideal bool value.
 type Bool BoolExact

--- a/pkg/prop/duration.go
+++ b/pkg/prop/duration.go
@@ -1,9 +1,7 @@
 package prop

 import (
-	"fmt"
 	"math"
-	"strings"
 	"time"
 )

@@ -25,11 +23,6 @@ func (d Duration) Compare(a time.Duration) (float64, bool) {
 // Value implements DurationConstraint.
 func (d Duration) Value() (time.Duration, bool) { return time.Duration(d), true }

-// String implements Stringify
-func (d Duration) String() string {
-	return fmt.Sprintf("%v (ideal)", time.Duration(d))
-}
-
 // DurationExact specifies exact duration value.
 type DurationExact time.Duration

@@ -44,11 +37,6 @@ func (d DurationExact) Compare(a time.Duration) (float64, bool) {
 // Value implements DurationConstraint.
 func (d DurationExact) Value() (time.Duration, bool) { return time.Duration(d), true }

-// String implements Stringify
-func (d DurationExact) String() string {
-	return fmt.Sprintf("%v (exact)", time.Duration(d))
-}
-
 // DurationOneOf specifies list of expected duration values.
 type DurationOneOf []time.Duration

@@ -65,16 +53,6 @@ func (d DurationOneOf) Compare(a time.Duration) (float64, bool) {
 // Value implements DurationConstraint.
 func (DurationOneOf) Value() (time.Duration, bool) { return 0, false }

-// String implements Stringify
-func (d DurationOneOf) String() string {
-	var opts []string
-	for _, v := range d {
-		opts = append(opts, fmt.Sprint(v))
-	}
-
-	return fmt.Sprintf("%s (one of values)", strings.Join(opts, ","))
-}
-
 // DurationRanged specifies range of expected duration value.
 // If Ideal is non-zero, closest value to Ideal takes priority.
 type DurationRanged struct {
@@ -118,8 +96,3 @@ func (d DurationRanged) Compare(a time.Duration) (float64, bool) {

 // Value implements DurationConstraint.
 func (DurationRanged) Value() (time.Duration, bool) { return 0, false }
-
-// String implements Stringify
-func (d DurationRanged) String() string {
-	return fmt.Sprintf("%s - %s (range), %s (ideal)", d.Min, d.Max, d.Ideal)
-}
--- a/Show More
+++ b/Show More