// Code layout taken from http://www.mozbox.org/pub/green/main.js

var processor = {
	doLoad: function() {
		this.video = document.getElementById("video");
		
		this.c1 = document.createElement("canvas");
		this.c1.width = "160"
		this.c1.height = "96"
		this.ctx1 = this.c1.getContext("2d");
		
		this.c2 = document.getElementById("c2");
		this.ctx2 = this.c2.getContext("2d");
		
		var self = this;
		this.video.addEventListener("play", function() {
			self.width = self.video.videoWidth / 2;
			self.height = self.video.videoHeight / 2;
			self.len = self.width * self.height;
			
			self.video.addEventListener('timeupdate', function(event) {
				self.computeFrame()
			}, true);
		}, false);
	},

	computeFrame: function() {
		var frame, data, i, num, rgba
		
		this.ctx1.drawImage(this.video, 0, 0, this.width, this.height);
		frame = this.ctx1.getImageData(0, 0, this.width, this.height);
		data = frame.data;
		
		num = Math.floor(Math.random()*3)
		
		for (i = 0; i < this.len; i++) {
			rgba = data.getPixel(i);
			
			data.setPixel(i, 0, rgba[num]);
			data.setPixel(i, 1, rgba[num]);
			data.setPixel(i, 2, rgba[num]);
		}
		this.ctx2.putImageData(frame, 0, 0);
		return;
	}
};

Array.prototype.getPixel = function(number) {
	var real = number * 4;
	return this.slice(real, real + 4);
};

Array.prototype.setPixel = function(number, rgba, val) {
	var real = number * 4 + rgba;
	if (number < 0 || real > this.length)
		return;
	this[real] = val;
};