Compare commits

..

1 Commits

Author SHA1 Message Date
renovate[bot]
34cf78091e fix(deps): update module github.com/pion/webrtc/v4 to v4.1.6
Generated by Renovate Bot
2025-10-27 01:38:15 +00:00
11 changed files with 14 additions and 542 deletions

View File

@@ -27,7 +27,6 @@ jobs:
sudo apt-get update -qq \
&& sudo apt-get install --no-install-recommends -y \
libopus-dev \
libsvtav1enc-dev \
libva-dev \
libvpx-dev \
libx11-dev \
@@ -56,10 +55,9 @@ jobs:
run: |
which brew
brew install \
libvpx \
opus \
pkg-config \
svt-av1 \
opus \
libvpx \
x264
- name: Run Test Suite
run: make test

View File

@@ -149,14 +149,6 @@ A codec library which supports H.264 encoding and decoding. It is suitable for u
* 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
##### svtav1
A free software video codec library from the Alliance for Open Media that implements AV1 video coding formats.
* Package: [github.com/pion/mediadevices/pkg/codec/svtav1](https://pkg.go.dev/github.com/pion/mediadevices/pkg/codec/svtav1)
* Installation:
* Mac: `brew install svt-av1`
* Ubuntu: `apt install libsvtav1enc-dev`
##### vpx
A free software video codec library from Google and the Alliance for Open Media that implements VP8/VP9 video coding formats.

View File

@@ -5,7 +5,7 @@ go 1.21
require (
github.com/esimov/pigo v1.4.6
github.com/pion/mediadevices v0.0.0
github.com/pion/webrtc/v4 v4.1.5
github.com/pion/webrtc/v4 v4.1.6
)
require (
@@ -21,7 +21,7 @@ require (
github.com/pion/randutil v0.1.0 // indirect
github.com/pion/rtcp v1.2.16 // indirect
github.com/pion/rtp v1.8.24 // indirect
github.com/pion/sctp v1.8.39 // indirect
github.com/pion/sctp v1.8.40 // indirect
github.com/pion/sdp/v3 v3.0.16 // indirect
github.com/pion/srtp/v3 v3.0.8 // indirect
github.com/pion/stun/v3 v3.0.0 // indirect

View File

@@ -29,8 +29,8 @@ github.com/pion/rtcp v1.2.16 h1:fk1B1dNW4hsI78XUCljZJlC4kZOPk67mNRuQ0fcEkSo=
github.com/pion/rtcp v1.2.16/go.mod h1:/as7VKfYbs5NIb4h6muQ35kQF/J0ZVNz2Z3xKoCBYOo=
github.com/pion/rtp v1.8.24 h1:+ICyZXUQDv95EsHN70RrA4XKJf5MGWyC6QQc1u6/ynI=
github.com/pion/rtp v1.8.24/go.mod h1:rF5nS1GqbR7H/TCpKwylzeq6yDM+MM6k+On5EgeThEM=
github.com/pion/sctp v1.8.39 h1:PJma40vRHa3UTO3C4MyeJDQ+KIobVYRZQZ0Nt7SjQnE=
github.com/pion/sctp v1.8.39/go.mod h1:cNiLdchXra8fHQwmIoqw0MbLLMs+f7uQ+dGMG2gWebE=
github.com/pion/sctp v1.8.40 h1:bqbgWYOrUhsYItEnRObUYZuzvOMsVplS3oNgzedBlG8=
github.com/pion/sctp v1.8.40/go.mod h1:SPBBUENXE6ThkEksN5ZavfAhFYll+h+66ZiG6IZQuzo=
github.com/pion/sdp/v3 v3.0.16 h1:0dKzYO6gTAvuLaAKQkC02eCPjMIi4NuAr/ibAwrGDCo=
github.com/pion/sdp/v3 v3.0.16/go.mod h1:9tyKzznud3qiweZcD86kS0ff1pGYB3VX+Bcsmkx6IXo=
github.com/pion/srtp/v3 v3.0.8 h1:RjRrjcIeQsilPzxvdaElN0CpuQZdMvcl9VZ5UY9suUM=
@@ -41,8 +41,8 @@ github.com/pion/transport/v3 v3.0.8 h1:oI3myyYnTKUSTthu/NZZ8eu2I5sHbxbUNNFW62ola
github.com/pion/transport/v3 v3.0.8/go.mod h1:+c2eewC5WJQHiAA46fkMMzoYZSuGzA/7E2FPrOYHctQ=
github.com/pion/turn/v4 v4.1.1 h1:9UnY2HB99tpDyz3cVVZguSxcqkJ1DsTSZ+8TGruh4fc=
github.com/pion/turn/v4 v4.1.1/go.mod h1:2123tHk1O++vmjI5VSD0awT50NywDAq5A2NNNU4Jjs8=
github.com/pion/webrtc/v4 v4.1.5 h1:hJqfKPdRAVcXV9rsg2xcCiuXuMJ38BLW/87GsYJUtUU=
github.com/pion/webrtc/v4 v4.1.5/go.mod h1:vzHh7egVnZRgkK83lYzciWVszdDs759y3/eyu6AvZRA=
github.com/pion/webrtc/v4 v4.1.6 h1:srHH2HwvCGwPba25EYJgUzgLqCQoXl1VCUnrGQMSzUw=
github.com/pion/webrtc/v4 v4.1.6/go.mod h1:wKecGRlkl3ox/As/MYghJL+b/cVXMEhoPMJWPuGQFhU=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=

4
go.mod
View File

@@ -11,7 +11,7 @@ require (
github.com/pion/logging v0.2.4
github.com/pion/rtcp v1.2.16
github.com/pion/rtp v1.8.24
github.com/pion/webrtc/v4 v4.1.5
github.com/pion/webrtc/v4 v4.1.6
github.com/stretchr/testify v1.11.1
golang.org/x/image v0.23.0
)
@@ -27,7 +27,7 @@ require (
github.com/pion/ice/v4 v4.0.10 // indirect
github.com/pion/mdns/v2 v2.0.7 // indirect
github.com/pion/randutil v0.1.0 // indirect
github.com/pion/sctp v1.8.39 // indirect
github.com/pion/sctp v1.8.40 // indirect
github.com/pion/sdp/v3 v3.0.16 // indirect
github.com/pion/srtp/v3 v3.0.8 // indirect
github.com/pion/stun/v3 v3.0.0 // indirect

8
go.sum
View File

@@ -40,8 +40,8 @@ github.com/pion/rtcp v1.2.16 h1:fk1B1dNW4hsI78XUCljZJlC4kZOPk67mNRuQ0fcEkSo=
github.com/pion/rtcp v1.2.16/go.mod h1:/as7VKfYbs5NIb4h6muQ35kQF/J0ZVNz2Z3xKoCBYOo=
github.com/pion/rtp v1.8.24 h1:+ICyZXUQDv95EsHN70RrA4XKJf5MGWyC6QQc1u6/ynI=
github.com/pion/rtp v1.8.24/go.mod h1:rF5nS1GqbR7H/TCpKwylzeq6yDM+MM6k+On5EgeThEM=
github.com/pion/sctp v1.8.39 h1:PJma40vRHa3UTO3C4MyeJDQ+KIobVYRZQZ0Nt7SjQnE=
github.com/pion/sctp v1.8.39/go.mod h1:cNiLdchXra8fHQwmIoqw0MbLLMs+f7uQ+dGMG2gWebE=
github.com/pion/sctp v1.8.40 h1:bqbgWYOrUhsYItEnRObUYZuzvOMsVplS3oNgzedBlG8=
github.com/pion/sctp v1.8.40/go.mod h1:SPBBUENXE6ThkEksN5ZavfAhFYll+h+66ZiG6IZQuzo=
github.com/pion/sdp/v3 v3.0.16 h1:0dKzYO6gTAvuLaAKQkC02eCPjMIi4NuAr/ibAwrGDCo=
github.com/pion/sdp/v3 v3.0.16/go.mod h1:9tyKzznud3qiweZcD86kS0ff1pGYB3VX+Bcsmkx6IXo=
github.com/pion/srtp/v3 v3.0.8 h1:RjRrjcIeQsilPzxvdaElN0CpuQZdMvcl9VZ5UY9suUM=
@@ -52,8 +52,8 @@ github.com/pion/transport/v3 v3.0.8 h1:oI3myyYnTKUSTthu/NZZ8eu2I5sHbxbUNNFW62ola
github.com/pion/transport/v3 v3.0.8/go.mod h1:+c2eewC5WJQHiAA46fkMMzoYZSuGzA/7E2FPrOYHctQ=
github.com/pion/turn/v4 v4.1.1 h1:9UnY2HB99tpDyz3cVVZguSxcqkJ1DsTSZ+8TGruh4fc=
github.com/pion/turn/v4 v4.1.1/go.mod h1:2123tHk1O++vmjI5VSD0awT50NywDAq5A2NNNU4Jjs8=
github.com/pion/webrtc/v4 v4.1.5 h1:hJqfKPdRAVcXV9rsg2xcCiuXuMJ38BLW/87GsYJUtUU=
github.com/pion/webrtc/v4 v4.1.5/go.mod h1:vzHh7egVnZRgkK83lYzciWVszdDs759y3/eyu6AvZRA=
github.com/pion/webrtc/v4 v4.1.6 h1:srHH2HwvCGwPba25EYJgUzgLqCQoXl1VCUnrGQMSzUw=
github.com/pion/webrtc/v4 v4.1.6/go.mod h1:wKecGRlkl3ox/As/MYghJL+b/cVXMEhoPMJWPuGQFhU=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=

View File

@@ -1,127 +0,0 @@
#include <EbSvtAv1.h>
#include <EbSvtAv1Enc.h>
#include <EbSvtAv1ErrorCodes.h>
#include <stdbool.h>
#include <stdint.h>
#include <string.h>
#define ERR_INIT_ENC_HANDLER 1
#define ERR_SET_ENC_PARAM 2
#define ERR_ENC_INIT 3
#define ERR_SEND_PICTURE 4
#define ERR_GET_PACKET 5
typedef struct Encoder {
EbSvtAv1EncConfiguration *param;
EbComponentType *handle;
EbBufferHeaderType *in_buf;
bool force_keyframe;
} Encoder;
int enc_free(Encoder *e) {
free(e->in_buf->p_buffer);
free(e->in_buf);
free(e->param);
free(e);
return 0;
}
int enc_new(Encoder **e) {
*e = malloc(sizeof(Encoder));
(*e)->param = malloc(sizeof(EbSvtAv1EncConfiguration));
(*e)->in_buf = malloc(sizeof(EbBufferHeaderType));
memset((*e)->in_buf, 0, sizeof(EbBufferHeaderType));
(*e)->in_buf->p_buffer = malloc(sizeof(EbSvtIOFormat));
(*e)->in_buf->size = sizeof(EbBufferHeaderType);
#if SVT_AV1_CHECK_VERSION(3, 0, 0)
const EbErrorType sret = svt_av1_enc_init_handle(&(*e)->handle, (*e)->param);
#else
const EbErrorType sret = svt_av1_enc_init_handle(&(*e)->handle, NULL, (*e)->param);
#endif
if (sret != EB_ErrorNone) {
enc_free(*e);
return ERR_INIT_ENC_HANDLER;
}
return 0;
}
int enc_init(Encoder *e) {
EbErrorType sret;
e->param->encoder_bit_depth = 8;
e->param->encoder_color_format = EB_YUV420;
sret = svt_av1_enc_set_parameter(e->handle, e->param);
if (sret != EB_ErrorNone) {
return ERR_SET_ENC_PARAM;
}
sret = svt_av1_enc_init(e->handle);
if (sret != EB_ErrorNone) {
return ERR_ENC_INIT;
}
return 0;
}
int enc_apply_param(Encoder *e) {
const EbErrorType sret = svt_av1_enc_set_parameter(e->handle, e->param);
if (sret != EB_ErrorNone) {
return ERR_SET_ENC_PARAM;
}
return 0;
}
int enc_force_keyframe(Encoder *e) {
e->force_keyframe = true;
return 0;
}
int enc_send_frame(Encoder *e, uint8_t *y, uint8_t *cb, uint8_t *cr, int ystride, int cstride) {
EbSvtIOFormat *in_data = (EbSvtIOFormat *)e->in_buf->p_buffer;
in_data->luma = y;
in_data->cb = cb;
in_data->cr = cr;
in_data->y_stride = ystride;
in_data->cb_stride = cstride;
in_data->cr_stride = cstride;
e->in_buf->pic_type = EB_AV1_INVALID_PICTURE; // auto
if (e->force_keyframe) {
e->in_buf->pic_type = EB_AV1_KEY_PICTURE;
e->force_keyframe = false;
}
e->in_buf->flags = 0;
e->in_buf->pts++;
e->in_buf->n_filled_len = ystride * e->param->source_height;
e->in_buf->n_filled_len += 2 * cstride * e->param->source_height / 2;
const EbErrorType sret = svt_av1_enc_send_picture(e->handle, e->in_buf);
if (sret != EB_ErrorNone) {
return ERR_SEND_PICTURE;
}
return 0;
}
int enc_get_packet(Encoder *e, EbBufferHeaderType **out) {
const EbErrorType sret = svt_av1_enc_get_packet(e->handle, out, 0);
if (sret == EB_NoErrorEmptyQueue) {
return 0;
}
if (sret != EB_ErrorNone) {
return ERR_GET_PACKET;
}
return 0;
}
void memcpy_uint8(uint8_t *dst, const uint8_t *src, size_t n) {
// Just make CGO types compatible
memcpy(dst, src, n);
}

View File

@@ -1,14 +0,0 @@
package svtav1
import (
"errors"
)
var (
ErrUnknownErrorCode = errors.New("unknown error code")
ErrInitEncHandler = errors.New("failed to initialize encoder handler")
ErrSetEncParam = errors.New("failed to set encoder parameters")
ErrEncInit = errors.New("failed to initialize encoder")
ErrSendPicture = errors.New("failed to send picture")
ErrGetPacket = errors.New("failed to get packet")
)

View File

@@ -1,47 +0,0 @@
package svtav1
import (
"time"
"github.com/pion/mediadevices/pkg/codec"
"github.com/pion/mediadevices/pkg/io/video"
"github.com/pion/mediadevices/pkg/prop"
)
// Params stores libx264 specific encoding parameters.
type Params struct {
codec.BaseParams
// Preset configuration number of SVT-AV1
// 1-3: extremely high efficiency but heavy
// 4-6: a balance of efficiency and reasonable compute time
// 7-13: real-time encoding
Preset int
StartingBufferLevel time.Duration
OptimalBufferLevel time.Duration
MaximumBufferSize time.Duration
}
// NewParams returns default x264 codec specific parameters.
func NewParams() (Params, error) {
return Params{
BaseParams: codec.BaseParams{
KeyFrameInterval: 60,
},
Preset: 9,
StartingBufferLevel: 400 * time.Millisecond,
OptimalBufferLevel: 200 * time.Millisecond,
MaximumBufferSize: 500 * time.Millisecond,
}, nil
}
// RTPCodec represents the codec metadata
func (p *Params) RTPCodec() *codec.RTPCodec {
return codec.NewRTPAV1Codec(90000)
}
// BuildVideoEncoder builds x264 encoder with given params
func (p *Params) BuildVideoEncoder(r video.Reader, property prop.Media) (codec.ReadCloser, error) {
return newEncoder(r, property, *p)
}

View File

@@ -1,184 +0,0 @@
// Package svtav1 implements AV1 encoder.
// This package requires libSvtAv1Enc headers and libraries to be built.
package svtav1
// #cgo pkg-config: SvtAv1Enc
// #include "bridge.h"
import "C"
import (
"image"
"io"
"sync"
"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
outPool sync.Pool
}
func newEncoder(r video.Reader, p prop.Media, params Params) (codec.ReadCloser, error) {
var enc *C.Encoder
if p.FrameRate == 0 {
p.FrameRate = 30
}
if err := errFromC(C.enc_new(&enc)); err != nil {
return nil, err
}
enc.param.source_width = C.uint32_t(p.Width)
enc.param.source_height = C.uint32_t(p.Height)
enc.param.profile = C.MAIN_PROFILE
enc.param.enc_mode = C.int8_t(params.Preset)
enc.param.rate_control_mode = C.SVT_AV1_RC_MODE_CBR
enc.param.pred_structure = C.SVT_AV1_PRED_LOW_DELAY_B
enc.param.target_bit_rate = C.uint32_t(params.BitRate)
enc.param.frame_rate_numerator = C.uint32_t(p.FrameRate * 1000)
enc.param.frame_rate_denominator = 1000
enc.param.intra_refresh_type = C.SVT_AV1_KF_REFRESH
enc.param.intra_period_length = C.int32_t(params.KeyFrameInterval)
enc.param.starting_buffer_level_ms = C.int64_t(params.StartingBufferLevel.Milliseconds())
enc.param.optimal_buffer_level_ms = C.int64_t(params.OptimalBufferLevel.Milliseconds())
enc.param.maximum_buffer_size_ms = C.int64_t(params.MaximumBufferSize.Milliseconds())
if err := errFromC(C.enc_init(enc)); err != nil {
_ = C.enc_free(enc)
return nil, err
}
e := encoder{
engine: enc,
r: video.ToI420(r),
outPool: sync.Pool{
New: func() any {
return []byte(nil)
},
},
}
return &e, nil
}
func errFromC(ret C.int) error {
switch ret {
case 0:
return nil
case C.ERR_INIT_ENC_HANDLER:
return ErrInitEncHandler
case C.ERR_SET_ENC_PARAM:
return ErrSetEncParam
case C.ERR_ENC_INIT:
return ErrEncInit
case C.ERR_SEND_PICTURE:
return ErrSendPicture
case C.ERR_GET_PACKET:
return ErrGetPacket
default:
return ErrUnknownErrorCode
}
}
func (e *encoder) Read() ([]byte, func(), error) {
e.mu.Lock()
defer e.mu.Unlock()
if e.closed {
return nil, func() {}, io.EOF
}
for {
img, release, err := e.r.Read()
if err != nil {
return nil, func() {}, err
}
defer release()
yuvImg := img.(*image.YCbCr)
if err := errFromC(C.enc_send_frame(
e.engine,
(*C.uchar)(&yuvImg.Y[0]),
(*C.uchar)(&yuvImg.Cb[0]),
(*C.uchar)(&yuvImg.Cr[0]),
C.int(yuvImg.YStride),
C.int(yuvImg.CStride),
)); err != nil {
return nil, func() {}, err
}
var buf *C.EbBufferHeaderType
if err := errFromC(C.enc_get_packet(e.engine, &buf)); err != nil {
return nil, func() {}, err
}
if buf == nil {
// Feed frames until receiving a packet
continue
}
n := int(buf.n_filled_len)
outBuf := e.outPool.Get().([]byte)
if cap(outBuf) < n {
outBuf = make([]byte, n)
} else {
outBuf = outBuf[:n]
}
C.memcpy_uint8((*C.uchar)(&outBuf[0]), buf.p_buffer, C.size_t(n))
C.svt_av1_enc_release_out_buffer(&buf)
return outBuf, func() {
e.outPool.Put(outBuf)
}, err
}
}
func (e *encoder) ForceKeyFrame() error {
e.mu.Lock()
defer e.mu.Unlock()
if err := errFromC(C.enc_force_keyframe(e.engine)); err != nil {
return err
}
return nil
}
func (e *encoder) SetBitRate(bitrate int) error {
e.mu.Lock()
defer e.mu.Unlock()
e.engine.param.target_bit_rate = C.uint32_t(bitrate)
if err := errFromC(C.enc_apply_param(e.engine)); err != nil {
return err
}
return nil
}
func (e *encoder) Controller() codec.EncoderController {
return e
}
func (e *encoder) Close() error {
e.mu.Lock()
defer e.mu.Unlock()
if e.closed {
return nil
}
if err := errFromC(C.enc_free(e.engine)); err != nil {
return err
}
e.closed = true
return nil
}

View File

@@ -1,146 +0,0 @@
package svtav1
import (
"image"
"testing"
"github.com/pion/mediadevices/pkg/codec"
"github.com/pion/mediadevices/pkg/codec/internal/codectest"
"github.com/pion/mediadevices/pkg/frame"
"github.com/pion/mediadevices/pkg/io/video"
"github.com/pion/mediadevices/pkg/prop"
)
func getTestVideoEncoder() (codec.ReadCloser, error) {
p, err := NewParams()
if err != nil {
return nil, err
}
p.BitRate = 200000
enc, err := p.BuildVideoEncoder(video.ReaderFunc(func() (image.Image, func(), error) {
return image.NewYCbCr(
image.Rect(0, 0, 256, 144),
image.YCbCrSubsampleRatio420,
), nil, nil
}), prop.Media{
Video: prop.Video{
Width: 256,
Height: 144,
FrameFormat: frame.FormatI420,
},
})
if err != nil {
return nil, err
}
return enc, nil
}
func TestEncoder(t *testing.T) {
t.Run("SimpleRead", func(t *testing.T) {
p, err := NewParams()
if err != nil {
t.Fatal(err)
}
p.BitRate = 200000
codectest.VideoEncoderSimpleReadTest(t, &p,
prop.Media{
Video: prop.Video{
Width: 256,
Height: 144,
FrameFormat: frame.FormatI420,
},
},
image.NewYCbCr(
image.Rect(0, 0, 256, 144),
image.YCbCrSubsampleRatio420,
),
)
})
t.Run("CloseTwice", func(t *testing.T) {
p, err := NewParams()
if err != nil {
t.Fatal(err)
}
p.BitRate = 200000
codectest.VideoEncoderCloseTwiceTest(t, &p, prop.Media{
Video: prop.Video{
Width: 640,
Height: 480,
FrameRate: 30,
FrameFormat: frame.FormatI420,
},
})
})
t.Run("ReadAfterClose", func(t *testing.T) {
p, err := NewParams()
if err != nil {
t.Fatal(err)
}
p.BitRate = 200000
codectest.VideoEncoderReadAfterCloseTest(t, &p,
prop.Media{
Video: prop.Video{
Width: 256,
Height: 144,
FrameFormat: frame.FormatI420,
},
},
image.NewYCbCr(
image.Rect(0, 0, 256, 144),
image.YCbCrSubsampleRatio420,
),
)
})
}
func TestShouldImplementKeyFrameControl(t *testing.T) {
e := &encoder{}
if _, ok := e.Controller().(codec.KeyFrameController); !ok {
t.Error()
}
}
func TestNoErrorOnForceKeyFrame(t *testing.T) {
enc, err := getTestVideoEncoder()
if err != nil {
t.Fatal(err)
}
kfc, ok := enc.Controller().(codec.KeyFrameController)
if !ok {
t.Fatal("Failed to get KeyFrameController")
}
if err := kfc.ForceKeyFrame(); err != nil {
t.Error(err)
}
_, rel, err := enc.Read() // try to read the encoded frame
rel()
if err != nil {
t.Fatal(err)
}
}
func TestShouldImplementBitRateControl(t *testing.T) {
e := &encoder{}
if _, ok := e.Controller().(codec.BitRateController); !ok {
t.Error()
}
}
func TestNoErrorOnSetBitRate(t *testing.T) {
enc, err := getTestVideoEncoder()
if err != nil {
t.Fatal(err)
}
brc, ok := enc.Controller().(codec.BitRateController)
if !ok {
t.Fatal("Failed to get BitRateController")
}
if err := brc.SetBitRate(1000); err != nil { // 1000 bit/second is ridiculously low, but this is a testcase.
t.Error(err)
}
_, rel, err := enc.Read() // try to read the encoded frame
rel()
if err != nil {
t.Fatal(err)
}
}