node-demux

Node-Demux is a node.js package that decodes video files into raw frames in real-time. This is useful for creating a video player.

Prerequisites

FFMpeg (for developers)

Windows
- Download FFMpeg (Shared and Dev - 64bit)
- Use 7-zip to extract downloads
- Create folder 'C:\Dev' if it does not already exist
- Move extracted FFMpeg Shared folder to 'C:\Dev\ffmpeg-win64-shared'
- Move extracted FFMpeg Dev folder to 'C:\Dev\ffmpeg-win64-dev'
- Add 'C:\Dev\ffmpeg-win64-shared\bin' to your system Path variable
Mac OS X
- brew install ffmpeg --with-libvpx --with-libvorbis --with-ffplay
Linux
- Install FFMpeg and FFMpeg-Dev from your package manager (may need at add repository prior to install)

Install

npm install node-demux
- Note: Windows users may need option to specify compiler --msvc_version=2013

Usage

declare new demuxer: var video = new demux();

Method	Use
`video.load(filename, options)`	loads video from file (`filename` is path or url to desired file, `options` is an optional object)
`video.play()`	starts demuxing video (callback for `'start'` when it begins and `'frame'` on each new decoded frame
`video.pause(callback)`	pauses demuxing (`callback` is called once video successfully pauses decoding
`video.stop(callback)`	stops demuxing (same as pause, but also seeks video back to start)
`video.seek(timestamp, callback)`	seeks video to desired time in seconds (`callback` is called once video successfully finished seek)
`video.nextFrame()`	decodes next frame as soon as possible (`'frame'` message will be called)
`video.on(message)`	`message` is one of `'error'`, `'metadata'`, `'start'`, `'end'`, or `'frame'`

Load Options

Option	Meaning
`decodeFirstFrame`	boolean flag: decodes one frame after load, seek, or stop
`colorspace`	string: desired frame colorspace (`'yuv420p'` or `'rgb24'`)

Example

var demux = require('node-demux');

var start;
var nframes;

var video = new demux();
video.on('error', function(err) {
    console.log(err);
});
video.on('metadata', function(metadata) {
    nframes = 0;
    console.log(metadata);
});
video.on('start', function() {
    start = Date.now();
    console.log("start demuxing");
});
video.on('end', function() {
    var time = (Date.now() - start) / 1000;
    console.log("finished demuxing");
    console.log("  total time: " + time.toFixed(3) + "sec");
    console.log("  average frames per second: " + (nframes/time).toFixed(3) + "fps");
});
video.on('frame', function(frameIdx, data) {
    nframes++;
    console.log("received frame " + frameIdx + " (size: " + data.length + ")");
});
video.load("big-buck-bunny_trailer.mp4");
video.play();

tmarrinan / node-demux