node-gstreamer-superficial

Superficial GStreamer binding

What?

This is a superficial binding of GStreamer to nodejs. It does not attempt at being a complete binding, and will hopefully one day be replaced by (or implemented with) node-gir.

How?

var gstreamer = require('gstreamer-superficial');
var pipeline = new gstreamer.Pipeline("videotestsrc ! textoverlay name=text ! autovideosink");
pipeline.play();

Then, you can find an element within the pipeline, and set its properties:

var target = pipeline.findChild("text");

target.set("text", "Hello");
target.set( {
	"text":"Hello", 
	"font-desc":"Helvetica 32",
	} );

(see also examples/basic-pipeline.js)

Pipeline also knows .stop(), .pause() and .pollBus(), the elements returned by findChild support .set(object) and .set(name,value), appsinks also support .pull (see below).

Polling the GStreamer Pipeline Bus

You can asynchronously handle bus messages using Pipeline.pollBus(callback):

pipeline.pollBus( function(msg) {
	console.log( msg );
});

(see also examples/bus.js)

Handling binary data

You can feast off GStreamer's appsink to handle binary data. .pull starts a background work queue and calls your callback whenever a buffer is (or caps are) available:

var appsink = pipeline.findChild("sink");

appsink.pull( function(buf) {
	console.log("BUFFER size",buf.length);
}, function(caps) {
	console.log("CAPS",caps);
} );

(see examples/appsink.js)

A simple Ogg/Theora streaming server

is implemented in examples/streaming, just run server.js (requires express) and point your browser to http://localhost:8001. (Tested only with Chromium). This handles retaining the streamheader to feed first to every newly connected client.

Who?

gstreamer-superficial was written by Daniel Turing (mail AT danielturing.com) and currently licensed under the GPLv3. Pester me if you prefer a different License..