qrdecode.js

/*
       QR-Logo: http://qrlogo.kaarposoft.dk

       Copyright (C) 2011 Henrik Kaare Poulsen

       Licensed under the Apache License, Version 2.0 (the "License");
       you may not use this file except in compliance with the License.
       You may obtain a copy of the License at

	 http://www.apache.org/licenses/LICENSE-2.0

       Unless required by applicable law or agreed to in writing, software
       distributed under the License is distributed on an "AS IS" BASIS,
       WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
       See the License for the specific language governing permissions and
       limitations under the License.
*/


/* ************************************************************ */
/* Settings for http://www.jslint.com/
** Note that we do NOT adhere to all jslint proposals
*/

/*jslint
	white,
	single,
	this,
	for,
	long,
	browser,
*/
/*global
	alert,
	QRCodeDecode,
	Logger,
	canvas_loader,
	Modernizr,
*/


/* ************************************************************ */
/* JavaScript STRICT mode
*/

"use strict";


/* ************************************************************ */
function qrdecode_onload() {
	document.getElementById("nojs").style.display = "none";
	if (Modernizr.canvas && Modernizr.filereader) { document.getElementById("noHTML5canvas").style.display = "none"; }
	var qparms = getQueryParams(document.location.search);
	var url = qparms.url;
	if (url) {
		setTimeout(function () {
			canvas_url_loader(url, document.getElementById("qrlogo_canvas"), on_logo_loaded);
		}, 0);
	}
}


/* ************************************************************ */
function on_logo_loaded() {
	document.getElementById("ondecode_button").disabled = false;
	document.getElementById("div_decoded").style.display = "none";
	document.getElementById("div_debug").style.display = "none";
}



/* ************************************************************ */
function on_logo_file_upload(evt) {

	canvas_loader(evt, document.getElementById("qrlogo_canvas"), on_logo_loaded);
}


/* ************************************************************ */
function qrdecode_ondecode() {

	console.info("qrdecode_ondecode: Decoding QR Code");
	console.time("qrdecode_ondecode");

	document.getElementById("qrlogo_text").value = "";

	var qr = new QRCodeDecode();

	var debug = document.getElementById("qrlogo_debug_checkbox").checked;
	var logger;
	if (debug) {
		logger = new Logger("div_debug_output");
		logger.init();
		qr.logger = logger;
		document.getElementById("div_debug").style.display = "block";
	}

	var canvas = document.getElementById("qrlogo_canvas");
	var ctx = canvas.getContext("2d");
	var imagedata = ctx.getImageData(0, 0, canvas.width, canvas.height);

	var decoded = qr.decodeImageData(imagedata, canvas.width, canvas.height);

	document.getElementById("qrlogo_text").value = decoded;

	document.getElementById("div_decoded").style.display = "block";

	console.timeEnd("qrdecode_ondecode");
}