mp4box/src/box-write.js

JavaScript version of GPAC's MP4Box tool

/* 
 * Copyright (c) Telecom ParisTech/TSI/MM/GPAC Cyril Concolato
 * License: BSD-3-Clause (see LICENSE file)
 */
BoxParser.Box.prototype.writeHeader = function(stream, msg) {
	this.size += 8;
	if (this.size > MAX_SIZE) {
		this.size += 8;
	}
	if (this.type === "uuid") {
		this.size += 16;
	}
	Log.debug("BoxWriter", "Writing box "+this.type+" of size: "+this.size+" at position "+stream.getPosition()+(msg || ""));
	if (this.size > MAX_SIZE) {
		stream.writeUint32(1);
	} else {
		this.sizePosition = stream.getPosition();
		stream.writeUint32(this.size);
	}
	stream.writeString(this.type, null, 4);
	if (this.type === "uuid") {
		stream.writeUint8Array(this.uuid);
	}
	if (this.size > MAX_SIZE) {
		stream.writeUint64(this.size);
	} 
}

BoxParser.FullBox.prototype.writeHeader = function(stream) {
	this.size += 4;
	BoxParser.Box.prototype.writeHeader.call(this, stream, " v="+this.version+" f="+this.flags);
	stream.writeUint8(this.version);
	stream.writeUint24(this.flags);
}

BoxParser.Box.prototype.write = function(stream) {
	if (this.type === "mdat") {
		/* TODO: fix this */
		if (this.data) {
			this.size = this.data.length;
			this.writeHeader(stream);
			stream.writeUint8Array(this.data);
		}
	} else {
		this.size = (this.data ? this.data.length : 0);
		this.writeHeader(stream);
		if (this.data) {
			stream.writeUint8Array(this.data);
		}
	}
}

BoxParser.ContainerBox.prototype.write = function(stream) {
	this.size = 0;
	this.writeHeader(stream);
	for (var i=0; i<this.boxes.length; i++) {
		if (this.boxes[i]) {
			this.boxes[i].write(stream);
			this.size += this.boxes[i].size;
		}
	}
	/* adjusting the size, now that all sub-boxes are known */
	Log.debug("BoxWriter", "Adjusting box "+this.type+" with new size "+this.size);
	stream.adjustUint32(this.sizePosition, this.size);
}

BoxParser.TrackReferenceTypeBox.prototype.write = function(stream) {
	this.size = this.track_ids.length*4;
	this.writeHeader(stream);
	stream.writeUint32Array(this.track_ids);
}