Bring over changes from dash branch

README.adoc

@@ -3,7 +3,7 @@
 == Description
 
 Streamana is a Web page which streams your camera and microphone to YouTube Live
-(or any other HLS receiver). It uses https://github.com/davedoesdev/webm-muxer.js[webm-muxer.js] and
+(or any other HLS or DASH receiver). It uses https://github.com/davedoesdev/webm-muxer.js[webm-muxer.js] and
 https://github.com/davedoesdev/ffmpeg.js[ffmpeg.js].
 
 == Demo
@@ -15,7 +15,9 @@ Use Chrome 95 or later.
 .. Click _CREATE_ and then select _Go Live_ from the drop-down menu.
 .. Under _Select stream key_, select _Create new stream key_.
 .. Give your key a name.
-.. You must select _HLS_ as the streaming protocol.
+.. You must select _HLS_ as the streaming protocol. Note: YouTube DASH ingestion is only available
+   by using the Youtube API. See https://developers.google.com/youtube/v3/live/guides/encoding-with-dash#url-structure[here]
+   for more details.
 .. Click _CREATE_.
 .. Make sure the key you created is selected.
 .. Click _COPY_ next to _Stream URL_.
@@ -34,7 +36,7 @@ You can also change various options:
 ** Lock the camera to portrait mode (where available, e.g. mobile phones).
 ** Zoom the camera to fill the page.
 ** Select a different version of https://github.com/davedoesdev/ffmpeg.js[ffmpeg.js] to perform
-   the HLS encoding.
+   the HLS or DASH encoding.
 
 == Customisation
 
@@ -46,16 +48,16 @@ so you can change this to add video effects or overlays. The shader already hand
 resizing and rotating the video in `main()`. The optional greyscale conversion is in
 the `tpix()` function.
 
-The page's functionality is defined in link:site/streamana.js[] and link:site/hls.js[].
+The page's functionality is defined in link:site/streamana.js[] and link:site/streamer.js[].
 
-link:site/hls.js[] exports a class, `HLS`, which does the heavy lifting:
+link:site/streamer.js[] exports a class, `Streamer`, which does the heavy lifting:
 
 * The constructor takes the following arguments:
 ** The https://developer.mozilla.org/en-US/docs/Web/API/MediaStream[`MediaStream`]
    containing your video and audio tracks. Note that link:site/streamana.js[] supplies
    blank video when the camera is hidden and silent audio when the microphone is muted.
 ** The ingestion URL.
-** The URL of `ffmpeg-worker-hls.js` in https://github.com/davedoesdev/ffmpeg.js[ffmpeg.js].
+** The URL of `ffmpeg-worker-hls.js` or `ffmpeg-worker-dash.js` in https://github.com/davedoesdev/ffmpeg.js[ffmpeg.js].
    This allows your application (or the end user if required) to supply its own version,
    in accordance with LGPL.
 ** The desired video frame rate.
@@ -63,7 +65,7 @@ link:site/hls.js[] exports a class, `HLS`, which does the heavy lifting:
 * Call the `async start()` function to start streaming.
 * Call the `end()` function to stop streaming.
 
-`HLS` extends from https://developer.mozilla.org/en-US/docs/Web/API/EventTarget[`EventTarget`]
+`Streamer` extends from https://developer.mozilla.org/en-US/docs/Web/API/EventTarget[`EventTarget`]
 and dispatches the following events:
 
 * `start` when streaming has started.
@@ -80,7 +82,7 @@ Note that https://github.com/davedoesdev/ffmpeg.js[ffmpeg.js] is licensed under
 Streamana runs it inside a Web Worker and communicates with it via message passing.
 The end user can replace the version used by changing the URL in the user interface.
 
-Note also that the https://github.com/davedoesdev/ffmpeg.js[ffmpeg.js] HLS distribution
+Note also that the https://github.com/davedoesdev/ffmpeg.js[ffmpeg.js] HLS and DASH
-contains no H.264 or MP4 code. All encoding is done by the browser using
+distributions contain no H.264 or MP4 code. All encoding is done by the browser using
 https://developer.mozilla.org/en-US/docs/Web/API/MediaRecorder[`MediaRecorder`] or
 https://www.w3.org/TR/webcodecs/[WebCodecs].

site/gl-canvas.js

@@ -29,11 +29,12 @@ export class GlCanvas extends Canvas {
             }
         }), options);
         this.update_limiter = new UpdateLimiter();
+        this.destroyed = false;
     }
     // Allow rendering loop to be driven externally (e.g. by the audio encoder)
     // to avoid requestAnimationFrame (or indeed setInterval) throttling.
     onLoop() {
-        if (this.update_limiter.check()) {
+        if (this.update_limiter.check() && !this.destroyed) {
             const now = Date.now();
             this.checkRender();
             // Make sure we don't hog the main thread. Software rendering will take
@@ -50,14 +51,25 @@ export class GlCanvas extends Canvas {
     }
     // Prevent errors after destruction
     destroy() {
+        this.destroyed = true;
+        if (this.gl) {
             super.destroy();
+        }
         this.uniforms = {
             createTexture() {
                 return {};
             },
-            create() {}
+            create() {},
+            update() {}
+        };
+        this.textures = {
+            createOrUpdate() {
+                return {
+                    then() {}
+                };
+            },
+            values: {}
         };
-        this.textures = {};
         this.buffers = {
             values: {}
         };

site/mux-receiver.js

@@ -8,7 +8,7 @@ export class MuxReceiver extends EventTarget {
         }, 0);
     }
 
-    start({ ffmpeg_lib_url, ffmpeg_args, base_url }) {
+    start({ ffmpeg_lib_url, ffmpeg_args, base_url, protocol }) {
         this.worker = new Worker(ffmpeg_lib_url);
         this.worker.onerror = this.onerror.bind(this);
         this.worker.onmessage = e => {
@@ -48,7 +48,8 @@ export class MuxReceiver extends EventTarget {
                 case 'start-stream':
                     this.worker.postMessage({
                         type: 'base-url',
-                        data: base_url
+                        data: base_url,
+                        protocol
                     });
                     // falls through
                 case 'sending':

site/streamana.html

@@ -65,9 +65,22 @@
           <input id="zoom-video" class="form-check-input" type="checkbox">
           <label for="zoom-video" class="form-check-label">Minimize vertical bars in local video display</label>
         </div>
+        <div class="pt-4">
+          <label class="form-label">Ingestion protocol</label>
+          <div>
+          <div class="form-check form-check-inline">
+            <input id="protocol-hls" name="protocol" class="form-check-input" type="radio" value="ffmpeg-worker-hls.js">
+            <label for="protocol-hls" class="form-check-label">HLS (H.264)</label>
+          </div>
+          <div class="form-check form-check-inline">
+            <input id="protocol-dash" name="protocol" class="form-check-input" type="radio" value="ffmpeg-worker-dash.js">
+            <label for="protocol-dash" class="form-check-label">DASH (VP9)</label>
+          </div>
+          </div>
+        </div>
         <div class="pt-4">
           <label for="ffmpeg-lib-url" class="form-label">FFmpeg library URL</label>
-          <input id="ffmpeg-lib-url" class="form-control" placeholder="ffmpeg-worker-hls.js" type="text">
+          <input id="ffmpeg-lib-url" class="form-control" type="text">
         </div>
     </div>
     <div id="error-alert" class="alert alert-danger alert-dismissible fade mb-0 flex-grow-0" role="alert">

site/streamana.js

@@ -1,17 +1,14 @@
 import { GlCanvas } from './gl-canvas.js';
 import {
-    HLS,
+    get_default_config_from_url,
-    video_encoder_codec,
+    Streamer
-    videoBitsPerSecond
+} from './streamer.js';
-} from './hls.js';
 import shader from './shader.js';
 import {
     supported_video_configs,
     max_video_config,
 } from './resolution.js';
 
-const target_frame_rate = 30;
-
 const ingestion_url_el = document.getElementById('ingestion-url');
 ingestion_url_el.value = localStorage.getItem('streamana-ingestion-url');
 
@@ -39,25 +36,34 @@ const initial_ffmpeg_lib_url = (localStorage.getItem('streamana-ffmpeg-lib-url')
 if (initial_ffmpeg_lib_url) {
     ffmpeg_lib_url_el.value = initial_ffmpeg_lib_url;
 }
-ffmpeg_lib_url_el.addEventListener('input', function () {
+ffmpeg_lib_url_el.addEventListener('change', function () {
-    localStorage.setItem('streamana-ffmpeg-lib-url', this.value);
+    const value = this.value.trim();
+    localStorage.setItem('streamana-ffmpeg-lib-url', value);
+    if (value) {
+        protocol_hls_el.disabled = true;
+        protocol_dash_el.disabled = true;
+    } else {
+        protocol_hls_el.disabled = false;
+        protocol_dash_el.disabled = false;
+    }
+    set_ingestion();
 });
 
 const zoom_video_el = document.getElementById('zoom-video');
 zoom_video_el.checked = !!localStorage.getItem('streamana-zoom-video');
-zoom_video_el.addEventListener('input', function () {
+zoom_video_el.addEventListener('change', function () {
     localStorage.setItem('streamana-zoom-video', this.checked ? 'true' : '');
 });
 
 const lock_portrait_el = document.getElementById('lock-portrait');
 lock_portrait_el.checked = !!localStorage.getItem('streamana-lock-portrait');
-lock_portrait_el.addEventListener('input', function () {
+lock_portrait_el.addEventListener('change', function () {
     localStorage.setItem('streamana-lock-portrait', this.checked ? 'true' : '');
 });
 
 const greyscale_el = document.getElementById('greyscale');
 greyscale_el.checked = !!localStorage.getItem('streamana-greyscale');
-greyscale_el.addEventListener('input', function () {
+greyscale_el.addEventListener('change', function () {
     localStorage.setItem('streamana-greyscale', this.checked ? 'true' : '');
 });
 
@@ -106,13 +112,44 @@ camera_el.addEventListener('click', camera_save);
 
 const camera_swap_el = document.getElementById('camera-swap');
 
+const protocol_hls_el = document.getElementById('protocol-hls');
+const protocol_dash_el = document.getElementById('protocol-dash');
+const resolution_el = document.getElementById('resolution');
+
+let streamer_config;
 let video_config;
+const video_configs = new Map();
+
+function set_ingestion_protocol(protocol) {
+    if (protocol === 'dash') {
+        protocol_hls_el.checked = false;
+        protocol_dash_el.checked = true;
+        ffmpeg_lib_url_el.placeholder = protocol_dash_el.value;
+    } else {
+        protocol_hls_el.checked = true;
+        protocol_dash_el.checked = false;
+        ffmpeg_lib_url_el.placeholder = protocol_hls_el.value;
+    }
+}
+
+set_ingestion_protocol(localStorage.getItem('streamana-ingestion-protocol'));
+
+async function set_ingestion() {
+    const ffmpeg_lib_url = ffmpeg_lib_url_el.value.trim() ||
+                           ffmpeg_lib_url_el.placeholder.trim();
+
+    streamer_config = get_default_config_from_url(ffmpeg_lib_url);
+
+    set_ingestion_protocol(streamer_config.protocol);
+    localStorage.setItem('streamana-ingestion-protocol', streamer_config.protocol);
+
+    video_config = null;
     let preferred_resolution = localStorage.getItem('streamana-resolution');
     if (preferred_resolution) {
         video_config = await max_video_config({
             ...JSON.parse(preferred_resolution),
-        codec: video_encoder_codec,
+            ...streamer_config.video,
-        bitrate: videoBitsPerSecond
+            ...streamer_config.webcodecs.video
         }, true);
     }
     if (!video_config) {
@@ -120,15 +157,15 @@ if (!video_config) {
             width: 1280,
             height: 720,
             ratio: 16/9,
-        codec: video_encoder_codec,
+            ...streamer_config.video,
-        bitrate: videoBitsPerSecond
+            ...streamer_config.webcodecs.video
         }, true);
     }
-const resolution_el = document.getElementById('resolution');
+
-const video_configs = new Map();
+    resolution_el.innerHTML = '';
     for (let config of (await supported_video_configs({
-    codec: video_encoder_codec,
+        ...streamer_config.video,
-    bitrate: videoBitsPerSecond
+        ...streamer_config.webcodecs.video
     }, true)).filter(c => c.ratio >= 1)) {
         const option = document.createElement('option');
         option.innerHTML = `${config.width}x${config.height} — ${config.label}`;
@@ -136,7 +173,21 @@ for (let config of (await supported_video_configs({
         resolution_el.appendChild(option);
         video_configs.set(option.innerText, config);
     }
-resolution_el.addEventListener('change', function (ev) {
+}
+
+await set_ingestion();
+
+protocol_hls_el.addEventListener('change', function () {
+    ffmpeg_lib_url_el.placeholder = protocol_hls_el.value;
+    set_ingestion();
+});
+
+protocol_dash_el.addEventListener('change', function () {
+    ffmpeg_lib_url_el.placeholder = protocol_dash_el.value;
+    set_ingestion();
+});
+
+resolution_el.addEventListener('change', function () {
     video_config = video_configs.get(this.value);
     localStorage.setItem('streamana-resolution', JSON.stringify({
         width: video_config.width,
@@ -145,7 +196,7 @@ resolution_el.addEventListener('change', function (ev) {
     }));
 });
 
-let hls;
+let streamer;
 
 async function start() {
     const ingestion_url = ingestion_url_el.value.trim();
@@ -172,6 +223,8 @@ async function start() {
     lock_portrait_el.disabled = true;
     zoom_video_el.disabled = true;
     resolution_el.disabled = true;
+    protocol_hls_el.disabled = true;
+    protocol_dash_el.disabled = true;
     waiting_el.classList.remove('d-none');
     mic_el.removeEventListener('click', mic_save);
     camera_el.removeEventListener('click', camera_save);
@@ -218,7 +271,7 @@ async function start() {
             camera_icon_el.classList.add('off');
         }
         camera_el.addEventListener('click', camera_save);
-        greyscale_el.removeEventListener('input', greyscale);
+        greyscale_el.removeEventListener('change', greyscale);
         camera_swap_el.classList.add('d-none');
         camera_swap_el.removeEventListener('click', about_face);
         canvas_el_parent.classList.add('mx-auto');
@@ -267,8 +320,9 @@ async function start() {
                 track.stop();
             }
         }
-        if (hls) {
+        if (streamer) {
-            hls.end(!!err);
+            streamer.end(!!err);
+            streamer = null;
         }
 
         go_live_el.checked = false;
@@ -279,6 +333,8 @@ async function start() {
         lock_portrait_el.disabled = false;
         zoom_video_el.disabled = false;
         resolution_el.disabled = false;
+        protocol_hls_el.disabled = ffmpeg_lib_url_el.value.trim();
+        protocol_dash_el.disabled = ffmpeg_lib_url_el.value.trim();;
         waiting_el.classList.add('d-none');
         canvas_el.classList.add('d-none');
     }
@@ -356,7 +412,7 @@ async function start() {
         camera_swap_el.removeEventListener('click', about_face);
 
         async function finish() {
-            await hls.start();
+            await streamer.start();
             mic_el.addEventListener('click', media_toggle);
             camera_el.addEventListener('click', media_toggle);
             camera_swap_el.addEventListener('click', about_face);
@@ -375,8 +431,8 @@ async function start() {
             width: video_config.width,
             height: video_config.height,
             frameRate: {
-                ideal: target_frame_rate,
+                ideal: streamer_config.video.framerate,
-                max: target_frame_rate
+                max: streamer_config.video.framerate
             },
             facingMode: requested_facing_mode
         };
@@ -534,7 +590,7 @@ async function start() {
 
         // tell shader whether to greyscale
         gl_canvas.setUniform('u_greyscale', greyscale_el.checked);
-        greyscale_el.addEventListener('input', greyscale);
+        greyscale_el.addEventListener('change', greyscale);
 
         // tell shader camera hasn't started
         gl_canvas.setUniform('u_active', false);
@@ -572,7 +628,7 @@ async function start() {
         // capture video from the canvas
         // Note: Safari on iOS doesn't get any data, might be related to
         // https://bugs.webkit.org/show_bug.cgi?id=181663
-        canvas_stream = canvas_el.captureStream(target_frame_rate);
+        canvas_stream = canvas_el.captureStream(streamer_config.video.framerate);
 
         // add audio to canvas stream
         audio_dest = audio_context.createMediaStreamDestination();
@@ -593,11 +649,15 @@ async function start() {
         audio_source = silence;
         audio_source.connect(audio_dest);
 
-        // HLS from the canvas stream to the ingestion URL
+        // Stream from the canvas stream to the ingestion URL
-        hls = new HLS(canvas_stream, audio_context, ingestion_url, ffmpeg_lib_url, target_frame_rate, lock_portrait);
+        streamer = new Streamer(canvas_stream,
-        hls.addEventListener('run', () => console.log('HLS running'));
+                                audio_context,
-        hls.addEventListener('exit', ev => {
+                                ingestion_url,
-            const msg = `HLS exited with status ${ev.detail.code}`;
+                                streamer_config,
+                                lock_portrait);
+        streamer.addEventListener('run', () => console.log('Streamer running'));
+        streamer.addEventListener('exit', ev => {
+            const msg = `Streamer exited with status ${ev.detail.code}`;
             if (ev.detail.code === 0) {
                 console.log(msg);
                 cleanup();
@@ -605,8 +665,8 @@ async function start() {
                 cleanup(msg);
             }
         });
-        hls.addEventListener('error', cleanup);
+        streamer.addEventListener('error', cleanup);
-        hls.addEventListener('start', function () {
+        streamer.addEventListener('start', function () {
             if (done) {
                 this.end(true);
             }
@@ -616,7 +676,7 @@ async function start() {
             go_live_el.disabled = false;
             update();
         });
-        hls.addEventListener('update', update);
+        streamer.addEventListener('update', update);
 
         await start_media(facing_mode);
     } catch (ex) {
@@ -626,5 +686,5 @@ async function start() {
 
 function stop() {
     go_live_el.disabled = true;
-    hls.end();
+    streamer.end();
 }

site/streamer.js

@@ -1,20 +1,71 @@
 import { UpdateLimiter } from './update-limiter.js';
 import { MuxReceiver } from './mux-receiver.js';
 
-const audioBitsPerSecond = 128 * 1000;
-export const videoBitsPerSecond = 2500 * 1000;
 const key_frame_interval = 3;
 
-export const video_encoder_codec = 'avc1.42E01E' /*'avc1.42001E'*/;
+export function get_default_config_from_url(ffmpeg_lib_url) {
+    const protocol = ffmpeg_lib_url.indexOf('worker-dash') >= 0 ? 'dash' : 'hls';
+    return {
+        ffmpeg_lib_url,
+        protocol,
+        video: {
+            bitrate: 2500 * 1000,
+            framerate: 30
+        },
+        audio: {
+            bitrate: 128 * 1000
+        },
+        media_recorder: {
+            video: {
+                codec: protocol === 'dash' ? 'vp9' : 'H264',
+            },
+            audio: {
+                codec: 'opus'
+            },
+            webm: true,
+            mp4: false // requires ffmpeg-worker-hls.js or ffmpeg-worker-dash.js
+                       // to be configured with MP4 support (which is not the default)
+        },
+        webcodecs: {
+            video: {
+                ...(protocol === 'dash' ? {
+                    codec: 'vp09.00.10.08.01'
+                } : {
+                    codec: 'avc1.42E01E' /*'avc1.42001E'*/,
+                    avc: { format: 'annexb' }
+                })
+            },
+            audio: {
+                codec: 'opus' /*'pcm'*/,
+            },
+            webm_muxer: {
+                video: {
+                    codec: protocol === 'dash' ? 'V_VP9' : 'V_MPEG4/ISO/AVC'
+                },
+                audio: {
+                    codec: 'A_OPUS',
+                    bit_depth: 0 // 32 for pcm */
+                }
+            }
+        },
+        ffmpeg: {
+            video: {
+                codec: protocol === 'dash' ? 'libvpx-vp9' : 'libx264'
+            },
+            audio: {
+                codec: protocol === 'dash' ? 'libopus' : 'aac'
+            }
+        }
+    };
+}
 
-export class HLS extends EventTarget {
+export class Streamer extends EventTarget {
-    constructor(stream, audio_context, base_url, ffmpeg_lib_url, frame_rate, rotate) {
+    constructor(stream, audio_context, base_url, config, rotate) {
         super();
         this.stream = stream;
         this.audio_context = audio_context;
         this.base_url = base_url;
-        this.ffmpeg_lib_url = ffmpeg_lib_url;
+        this.config = config;
-        this.frame_rate = frame_rate;
         if (rotate) {
             this.ffmpeg_metadata = ['-metadata:s:v:0', 'rotate=-90'];
         } else {
@@ -30,25 +81,47 @@ export class HLS extends EventTarget {
             return;
         }
 
+        const mrcfg = this.config.media_recorder;
+
+        const mp4 = async () => {
+            if (mfcrg.mp4) {
+                // try MediaRecorder MP4 - this should work on Safari MacOS and iOS,
+                // producing H.264 video and AAC audio
+                await this.media_recorder('video/mp4');
+                console.log("Using MediaRecorder MP4 (H264,aac)");
+            } else {
+                throw new Error('no supported encoding methods');
+            }
+        };
+
+        const webcodecs = async () => {
+            const wccfg = this.config.webcodecs;
+            if (wccfg) {
                 try {
-            // first try WebM/H264 MediaRecorder - this should work on Chrome Linux and Windows
+                    // try WebCodecs - this should work on Chrome including Android
-            await this.media_recorder('video/webm;codecs=H264');
+                    await this.webcodecs();
-            console.log("Using MediaRecorder WebM/h264");
-        } catch (ex) {
-            console.warn(ex.toString());
-            try {
-                // next try WebCodecs - this should work on Chrome including Android
-                await this.webcodecs(video_encoder_codec,
-                                     'opus' /*'pcm'*/,
-                                     { avc: { format: 'annexb' } });
                     console.log("Using WebCodecs");
                 } catch (ex) {
                     console.warn(ex.toString());
-                // finally try MP4 - this should work on Safari MacOS and iOS, producing H264
+                    await mp4();
-                // this assumes ffmpeg-hls.js has been configured with MP4 support
-                await this.media_recorder('video/mp4');
-                console.log("Using MediaRecorder MP4");
                 }
+            } else {
+                await mp4();
+            }
+        };
+
+        if (mrcfg.webm) {
+            try {
+                // try MediaRecorder WebM - this should work on Chrome Linux and Windows
+                const codecs = `${mrcfg.video.codec},${mrcfg.audio.codec}`;
+                await this.media_recorder(`video/webm;codecs=${codecs}`);
+                console.log(`Using MediaRecorder WebM (${codecs})`);
+            } catch (ex) {
+                console.warn(ex.toString());
+                await webcodecs();
+            }
+        } else {
+            await webcodecs();
         }
 
         this.started = true;
@@ -59,7 +132,7 @@ export class HLS extends EventTarget {
         await this.audio_context.audioWorklet.addModule('./dummy-worklet.js');
         this.dummy_processor = new AudioWorkletNode(this.audio_context, 'dummy-processor', {
             processorOptions: {
-                update_rate: this.frame_rate
+                update_rate: this.config.video.framerate
             }
         });
         this.dummy_processor.onerror = onerror;
@@ -73,6 +146,30 @@ export class HLS extends EventTarget {
         this.dummy_processor.disconnect();
     }
 
+    receiver_args(video_codec, audio_codec) {
+        return {
+            ffmpeg_lib_url: this.config.ffmpeg_lib_url,
+            ffmpeg_args: [
+                '-i', '/work/stream1',
+                '-map', '0:v',
+                '-map', '0:a',
+                ...(video_codec === this.config.ffmpeg.video.codec ||
+                    video_codec === 'copy' ?
+                    ['-c:v', 'copy'] : // pass through the video data (no decoding or encoding)
+                    ['-c:v', this.config.ffmpeg.video.codec, // re-encode video
+                     '-b:v', this.config.video.bitrate.toString()]), // set video bitrate
+                ...this.ffmpeg_metadata,
+                ...(audio_codec === this.config.ffmpeg.audio.codec ||
+                    audio_codec === 'copy' ?
+                    ['-c:a', 'copy'] : // pass through the audio data
+                    ['-c:a', this.config.ffmpeg.audio.codec,  // re-encode audio
+                     '-b:a', this.config.audio.bitrate.toString()]) // set audio bitrate
+            ],
+            base_url: this.base_url,
+            protocol: this.config.protocol
+        };
+    }
+
     async media_recorder(mimeType) {
         const onerror = this.onerror.bind(this);
 
@@ -80,8 +177,8 @@ export class HLS extends EventTarget {
         // note we don't start recording until ffmpeg has started (below)
         const recorder = new MediaRecorder(this.stream, {
             mimeType,
-            audioBitsPerSecond,
+            videoBitsPerSecond: this.config.video.bitrate,
-            videoBitsPerSecond
+            audioBitsPerSecond: this.config.audio.bitrate
         });
         recorder.onerror = onerror;
 
@@ -101,27 +198,71 @@ export class HLS extends EventTarget {
 
         await this.start_dummy_processor();
 
+        let video_codec, audio_codec;
+        if (recorder.mimeType === 'video/mp4') {
+            video_codec = 'libx264';
+            audio_codec = 'aac';
+        } else {
+            switch (this.config.media_recorder.video.codec.toLowerCase()) {
+                case 'av1':
+                    video_codec = 'libaom-av1';
+                    break;
+
+                case 'h264':
+                    video_codec = 'libx264';
+                    break;
+
+                case 'vp8':
+                    video_codec = 'libvpx';
+                    break;
+
+                case 'vp9':
+                    video_codec = 'libvpx-vp9';
+                    break;
+
+                default:
+                    video_codec = null;
+                    break;
+            }
+
+            switch (this.config.media_recorder.audio.codec.toLowerCase()) {
+                case 'flac':
+                    audio_codec = 'flac';
+                    break;
+
+                case 'mp3':
+                    audio_codec = 'libmp3lame';
+                    break;
+
+                case 'opus':
+                    audio_codec = 'libopus';
+                    break;
+
+                case 'vorbis':
+                    audio_codec = 'libvorbis';
+                    break;
+
+                case 'pcm':
+                    audio_codec = 'f32le';
+                    break;
+
+                default:
+                    if (audio_codes.startsWith('mp4a')) {
+                        audio_codec = 'aac';
+                    } else {
+                        audio_codec = null;
+                    }
+                    break;
+            }
+        }
+
         // start the ffmpeg worker
         this.receiver = new MuxReceiver();
         this.receiver.addEventListener('message', e => {
             const msg = e.detail;
             switch (msg.type) {
                 case 'ready':
-                    this.receiver.start({
+                    this.receiver.start(this.receiver_args(video_codec, audio_codec));
-                        ffmpeg_lib_url: this.ffmpeg_lib_url,
-                        ffmpeg_args: [
-                            '-i', '/work/stream1',
-                            '-map', '0:v',
-                            '-map', '0:a',
-                            '-c:v', 'copy', // pass through the video data (h264, no decoding or encoding)
-                            ...this.ffmpeg_metadata,
-                            ...(recorder.mimeType === 'video/mp4' ?
-                                ['-c:a', 'copy'] : // assume already AAC
-                                ['-c:a', 'aac',  // re-encode audio as AAC-LC
-                                 '-b:a', audioBitsPerSecond.toString()]) // set audio bitrate
-                        ],
-                        base_url: this.base_url
-                    });
                     break;
 
                 case 'error':
@@ -153,7 +294,7 @@ export class HLS extends EventTarget {
         });
     }
 
-    async webcodecs(video_codec, audio_codec, video_config, audio_config) {
+    async webcodecs() {
         const onerror = this.onerror.bind(this);
 
         const video_track = this.stream.getVideoTracks()[0];
@@ -209,13 +350,11 @@ export class HLS extends EventTarget {
                         readable: video_readable,
                         key_frame_interval,
                         config: {
-                            codec: video_codec,
+                            ...this.config.video,
-                            bitrate: videoBitsPerSecond,
+                            ...this.config.webcodecs.video,
-                            framerate: this.frame_rate,
                             latencyMode: 'realtime',
                             width: video_settings.width,
                             height: video_settings.height,
-                            ...video_config
                         },
                     }, [video_readable]);
                     
@@ -224,11 +363,10 @@ export class HLS extends EventTarget {
                         audio: true,
                         readable: audio_readable,
                         config: {
-                            codec: audio_codec,
+                            ...this.config.audio,
-                            bitrate: audioBitsPerSecond,
+                            ...this.config.webcodecs.audio,
                             sampleRate: audio_settings.sampleRate,
                             numberOfChannels: audio_settings.channelCount,
-                            ...audio_config
                         },
                     }, [audio_readable]);
 
@@ -257,6 +395,60 @@ export class HLS extends EventTarget {
             }
         };
 
+        let video_codec;
+        switch (this.config.webcodecs.video.codec) {
+            case 'V_AV1':
+                video_codec = 'libaom-av1';
+                break;
+
+            case 'V_MPEG4/ISO/AVC':
+                video_codec = 'libx264';
+                break;
+
+            case 'V_VP8':
+                video_codec = 'libvpx';
+                break;
+
+            case 'V_VP9':
+                video_codec = 'libvpx-vp9';
+                break;
+
+            default:
+                video_codec = null;
+                break;
+        }
+
+        let audio_codec;
+        switch (this.config.webcodecs.audio.codec) {
+            case 'A_FLAC':
+                audio_codec = 'flac';
+                break;
+
+            case 'A_MPEG/L3':
+                audio_codec = 'libmp3lame';
+                break;
+
+            case 'A_OPUS':
+                audio_codec = 'libopus';
+                break;
+
+            case 'A_VORBIS':
+                audio_codec = 'libvorbis';
+                break;
+
+            case 'A_PCM/FLOAT/IEEE':
+                audio_codec = 'f32le';
+                break;
+
+            default:
+                if (audio_codes.startsWith('A_AAC')) {
+                    audio_codec = 'aac';
+                } else {
+                    audio_codec = null;
+                }
+                break;
+        }
+
         this.worker.postMessage({
             type: 'start',
             webm_metadata: {
@@ -264,28 +456,19 @@ export class HLS extends EventTarget {
                 video: {
                     width: video_settings.width,
                     height: video_settings.height,
-                    frame_rate: this.frame_rate,
+                    frame_rate: this.config.video.framerate,
-                    codec_id: 'V_MPEG4/ISO/AVC'
+                    codec_id: this.config.webcodecs.webm_muxer.video.codec
                 },
                 audio: {
                     sample_rate: audio_settings.sampleRate,
                     channels: audio_settings.channelCount,
-                    codec_id: 'A_OPUS'
+                    bit_depth: this.config.webcodecs.webm_muxer.audio.bit_depth,
+                    codec_id: this.config.webcodecs.webm_muxer.audio.codec
                 }
             },
             webm_receiver: './mux-receiver.js',
             webm_receiver_data: { name: 'stream1' },
-            ffmpeg_lib_url: this.ffmpeg_lib_url,
+            ...this.receiver_args(video_codec, audio_codec)
-            base_url: this.base_url,
-            ffmpeg_args: [
-                '-i', '/work/stream1',
-                '-map', '0:v',
-                '-map', '0:a',
-                '-c:v', 'copy', // pass through the video data (h264, no decoding or encoding)
-                ...this.ffmpeg_metadata,
-                '-c:a', 'aac',  // re-encode audio as AAC-LC
-                '-b:a', audioBitsPerSecond.toString() // set audio bitrate
-            ]
         });
     }