source: gs3-extensions/web-audio/trunk/js-mad/sink.js-master/src/extra/recording.js@ 28388

void function (Sink) {

Sink.on('init', function (sink) {
    sink.activeRecordings = [];
    sink.on('postprocess', sink.recordData);
});

Sink.prototype.activeRecordings = null;

/**
 * Starts recording the sink output.
 *
 * @method Sink
 * @name record
 *
 * @return {Recording} The recording object for the recording started.
*/
Sink.prototype.record = function () {
    var recording = new Sink.Recording(this);
    this.emit('record', [recording]);
    return recording;
};
/**
 * Private method that handles the adding the buffers to all the current recordings.
 *
 * @method Sink
 * @method recordData
 *
 * @arg {Array} buffer The buffer to record.
*/
Sink.prototype.recordData = function (buffer) {
    var activeRecs  = this.activeRecordings,
        i, l        = activeRecs.length;
    for (i=0; i<l; i++) {
        activeRecs[i].add(buffer);
    }
};

/**
 * A Recording class for recording sink output.
 *
 * @class
 * @static Sink
 * @arg {Object} bindTo The sink to bind the recording to.
*/

function Recording (bindTo) {
    this.boundTo = bindTo;
    this.buffers = [];
    bindTo.activeRecordings.push(this);
}

Recording.prototype = {
/**
 * Adds a new buffer to the recording.
 *
 * @arg {Array} buffer The buffer to add.
 *
 * @method Recording
*/
    add: function (buffer) {
        this.buffers.push(buffer);
    },
/**
 * Empties the recording.
 *
 * @method Recording
*/
    clear: function () {
        this.buffers = [];
    },
/**
 * Stops the recording and unbinds it from it's host sink.
 *
 * @method Recording
*/
    stop: function () {
        var recordings = this.boundTo.activeRecordings,
            i;
        for (i=0; i<recordings.length; i++) {
            if (recordings[i] === this) {
                recordings.splice(i--, 1);
            }
        }
    },
/**
 * Joins the recorded buffers into a single buffer.
 *
 * @method Recording
*/
    join: function () {
        var bufferLength    = 0,
            bufPos      = 0,
            buffers     = this.buffers,
            newArray,
            n, i, l     = buffers.length;

        for (i=0; i<l; i++) {
            bufferLength += buffers[i].length;
        }
        newArray = new Float32Array(bufferLength);
        for (i=0; i<l; i++) {
            for (n=0; n<buffers[i].length; n++) {
                newArray[bufPos + n] = buffers[i][n];
            }
            bufPos += buffers[i].length;
        }
        return newArray;
    }
};

Sink.Recording = Recording;

}(this.Sink);