1.1.0 • Published 8 years ago
node-demux v1.1.0
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
Pathvariable
- 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
- Note: Windows users may need option to specify compiler
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();