jMuxer - a simple javascript mp4 muxer that works in both browser and node environment. It is communication protocol agnostic and it is intended to play media files on the browser with the help of the media source extension. It also can export mp4 on the node environment. It expects raw H264 video data and/or AAC audio data in ADTS container as an input.
Click here to view a working demo
Click here to play a h264 file online
A distribution version is available on dist folder.
<script type="text/javascript" src="dist/jmuxer.min.js"></script>
var jmuxer = new JMuxer(option);
Available options are:
node - String ID of a video tag / Reference of the HTMLVideoElement. Required field for browsers.
mode - Available values are: both, video and audio. Default is both
flushingTime - Buffer flushing time in milliseconds. Default value is 500 milliseconds. Set flushingTime
to 0 if you want to flash buffer immediately or find any lag.
maxDelay - Maximum delay time in milliseconds. Default value is 500 milliseconds.
clearBuffer - true/false. Either it will clear played media buffer automatically or not. Default is true.
fps - Optional value. Frame rate of the video if it is known/fixed value. It will be used to find frame duration if chunk duration is not available with provided media data.
readFpsFromTrack - true/false. Will read FPS from MP4 track data instead of using (above) fps value. Default is false.
onReady - function. Will be called once MSE is ready.
onError - function. Will be fired if jMuxer encounters any buffer related errors.
onMissingVideoFrames - function. Will be fired if jMuxer encounters any missing video frames.
onMissingAudioFrames - function. Will be fired if jMuxer encounters any missing audio frames.
debug - true/false. Will print debug log in browser console. Default is false.
Complete example:
<script type="text/javascript" src="dist/jmuxer.min.js"></script>
<video id="player"></video>
<script>
var jmuxer = new JMuxer({
node: 'player',
mode: 'both', /* available values are: both, audio and video */
debug: false
});
/* Now feed media data using feed method. audio and video is buffer data and duration is in milliseconds */
jmuxer.feed({
audio: audio,
video: video,
duration: duration
});
</script>
Media dataObject may have following properties:
video - h264 buffer
audio - AAC buffer
duration - duration in milliseconds of the provided chunk. If duration is not provided, it will calculate frame duration wtih the provided frame rate (fps).
compositionTimeOffset - Composition time offset, difference between decode time and presentation time of frames, in milliseconds. This is only used for video and usually needed when B-frames are present in video stream.
ES6 Example:
Install module through npm
npm install --save jmuxer
import JMuxer from 'jmuxer';
const jmuxer = new JMuxer({
node: 'player',
debug: true
});
/* Now feed media data using feed method. audio and video is buffer data and duration is in milliseconds */
jmuxer.feed({
audio: audio,
video: video,
duration: duration
});
Node Example:
Install module through npm
npm install --save jmuxer
const JMuxer = require('jmuxer');
const jmuxer = new JMuxer({
debug: true
});
/*
Stream in Object mode. Please check the example file for more details
*/
let h264_feeder = getFeederStreamSomehow();
let http_or_ws_or_any = getWritterStreamSomehow();
h264_feeder.pipe(jmuxer.createStream()).pipe(http_or_ws_or_any);
Available Methods
Name | Parameter | Remark |
---|---|---|
feed | data object | object properites may have audio, video and duration. At least one media property i.e audio or video must be provided. If no duration is provided, it will calculate duration based on fps value |
createStream | - | Get a writeable stream to feed buffer. Available on NodeJS only |
reset | - | Reset the jmuxer and start over |
destroy | - | Destroy the jmuxer instance and release the resources |
Typescript definition
npm install --save @types/jmuxer
Compatibility
compatible with browsers supporting MSE with 'video/MP4. it is supported on:
- Chrome for Android 34+
- Chrome for Desktop 34+
- Firefox for Android 41+
- Firefox for Desktop 42+
- IE11+ for Windows 8.1+
- Edge for Windows 10+
- Opera for Desktop
- Safari for Mac 8+
A simple node server and some demo media data are available in the example directory. In the example, each chunk/packet is consist of 4 bytes of header and the payload following the header. The first two bytes of the header contain the chunk duration and remaining two bytes contain the audio data length. Packet format is shown in the image below:
Packet format
2 bytes | 2 bytes | ||
---|---|---|---|
Duration (ms) | Audio Data Length | Audio Data (AAC) | Video Data (H264) |
A step guideline to obtain above the packet format from your mp4 file using ffmpeg:
- Spliting video into 2 seconds chunks:
ffmpeg -i input.mp4 -c copy -map 0 -segment_time 2 -f segment %03d.mp4
- Extracting h264 for all chunks:
for f in *.mp4; do ffmpeg -i "$f" -vcodec copy -an -bsf:v h264_mp4toannexb "${f:0:3}.h264"; done
- Extracting audio for all chunks:
for f in *.mp4; do ffmpeg -i "$f" -acodec copy -vn "${f:0:3}.aac"; done
- Extracting duration for all chunks:
for f in *.mp4; do ffprobe "$f" -show_format 2>&1 | sed -n 's/duration=//p'; done
(see samirkumardas#20 (comment))
How to run example?
Demo files are available in example directory. For running the example, first run the node server by following command:
cd example
node server.js
then, visit example/index.html page using any webserver.
Assuming you are still in example
directory. Now run followngs:
node h264.js
then, visit example/h264.html page using any webserver.
A distribution version is available inside dist directory. However, if you need to build, you can do as follows:
- git clone https://github.com/samirkumardas/jmuxer.git
- cd jmuxer
- npm install
- npm run build OR npm run pro
If the project helps you, buy me a cup of coffee!
Proudly inspired by hls.js, rtsp player
Cobrowse.io - for sponsoring the adaptation of jMuxer for Node.js