FFmpeg-Stream

Stream based media converting library for Node.js.

Requires ffmpeg software installed and in PATH.

Examples

var ffmpeg = require('ffmpeg-stream').ffmpeg
  , fs = require('fs')
  , converter, input

converter = ffmpeg()

// get a writable input stream and pipe an image file to it
input = converter.input({f: 'image2pipe', vcodec: 'mjpeg'});
fs.createReadStream(__dirname + '/cat.jpg').pipe(input)

// create an output stream, crop/scale image, save to file via node stream
converter.output({
  f: 'image2', vcodec: 'mjpeg',
  vf: 'crop=300:300,scale=100:100',
})
.pipe(fs.createWriteStream(__dirname + '/cat_thumb.jpg'))

// same, but save to file directly from ffmpeg
converter.output(__dirname + '/cat_full.jpg', {vf: 'crop=300:300'})

// start processing
converter.run()

Example runnable scripts are in examples/ directory.

API

Class ffmpeg()

Creates and returns a new instance of the ffmpeg converter class. Converting won't start until ffmpeg.run() method is called.

method ffmpeg.input(path, options)

Defines an input. path argument can be skipped or null - in such case a writable stream is returned. The options argument is an object of ffmpeg option/value pairs.

Remember to specify format (f option) when using a stream as an input.

method ffmpeg.output(path, options)

Defines an output. path argument can be skipped or null - in such case a readable stream is returned. The options argument is an object of ffmpeg option/value pairs.

Remember to specify format (f option) when using a stream as an output.

The stream returned will be closed before the converter exits.

method ffmpeg.run()

Starts the processing.

event ffmpeg.on('finish', () => {…})

Emitted when the child ffmpeg process exits without error. This happens after the end event is fired on output streams.

event ffmpeg.on('error', (err) => {…})

Emitted when the child ffmpeg process exited with an error. The output streams are usually empty in this case.

Todos

• Add additional convenience APIs
  • Image resizing and thumbnail generation
  • Applying watermark to images
  • Video screenshots
• More examples
  • Streaming to HTTP response
  • POST request -> Converter -> MongoDB GridFS
• Better error messages
• Emit frame event for each frame transcoded
• Auto-detect input format (difficult when there's no filename)