Mike Hodnick's Blog

The End of Browser Plugins, First Hand

Posted: 22 December 2011

Until right about now, I've thought that plugins like Flash and Silverlight would have a place in this world. Click the button below. It will play a sound generated from a Javascript-based digital audio synthesis library. No plugin required.

Play Put your headphones on first!

The audio synthesis is performed with audiolib.js. audiolib.js can also do some crazy stuff with PCM/mp3 encoding, audio recording, and it even has a node.js install. Did I mention that no browser plugin is required?

Here's the code, based off of one of their tutorials:

var dev, osc, lfo, playing;

$(document).ready(function () {
    $('#playButton').click(function () {
        playing ? stop() : play();
    });
    dev = audioLib.AudioDevice(audioCallback, 2);
    osc = audioLib.Oscillator(dev.sampleRate, 440);
    osc.waveShape = 'triangle';
    lfo = audioLib.Oscillator(dev.sampleRate, 1.0);
    osc.addAutomation('frequency', lfo, .9, 'additiveModulation');

});

function play() {
    playing = true;
    $('#playButton').html('Stop');
}

function stop() {
    playing = false;
    $('#playButton').html('Play');
}

function audioCallback(buffer, channelCount) {
    if (playing) {
        lfo.generateBuffer(buffer.length / channelCount);
        osc.append(buffer, channelCount);
    }
}