Jsmpeglive NPM

jsmpeglive

An MPEG1 Video Decoder in JavaScript

jsmpeglive is a MPEG1 Live Video Decoder, written in JavaScript.

It receives a live stream, via WebSocket.

It is prepared to use any other Transport method available. It just needs to follow the same interface as the included built-in WebSocketClient.

This WebSocketClient has the logic to reconnect every 5 seconds

TODO: add some logarithmic/fibonacci/exponential back-off method

Setup

Run npm install and then npm start to start the HTTP and WebSockets server.

In an other terminal, Then, to start streaming, you can use a camera that provides a RTSP feed, or your own laptop

# Laptop Web cam feed
./start_ffmpeg_stream.sh /dev/video0

# Camera Feed
./start_ffmpeg_stream.sh "rtsp://192.168.1.54:554/axis-media/media.amp?videocodec=h264&resolution=640x480"

Building

To build, just run npm build

API

Constructor

var player = new jsmpeglive(uri[, options])

The uri argument accepts a WebSocket address for streaming playback.

The options argument to jsmpeglive() supports the following properties:

benchmark whether to log benchmark results to the browser's console
canvas the HTML Canvas element to use; jsmpeglive will create its own Canvas element if none is provided
ondecodeframe a function that's called after every frame that's decoded and rendered to the canvas

Examples

The best example is just checking the source code. Feel free to review stream-example.html.

Note that you have to include both WebSocketClient and jsmpeglive

var player = new jsmpeglive('ws://localhost:8084/', {canvas:canvas});

Diferences between `jsmpeglive` and `jsmpeg`

The Transport layer was removed from the main jsmpeg decoding object. Also, as I didn't need recording, it was removed, as well as all the functions for playing local video files.

Limitations

Only raw MPEG video streams are supported. The decoder hates Stream Packet Headers in between macroblocks.

You can use FFmpeg to encode videos in a suited format. Check start_ffmpeg_stream,sh, it has the parameters needed to crop the size to a multiple of 2, omit B-Frames and force a raw video stream.