QRCode

jQuery

(function ($) {
    $.fn.qrcode = function (options) {
        // if options is string, 
        if (typeof options === 'string') {
            options = {
                text: options
            };
        }

        // set default values
        options = $.extend({}, {
            width: 100,
            height: 100,
            background: "#ffffff",
            foreground: "#000000"
        }, options);

        var create = function () {
            // create the qrcode itself
            var qrcode = new QRCode(-1, QRErrorCorrectLevel.H),
				canvas,
				ctx,
				tileW = 0,
				tileH = 0,
				row =  0,
				col = 0,
				w = 0,
				h = 0;
				
            qrcode.addData(options.text);
            qrcode.make();

            // create canvas element
            canvas = document.createElement('canvas');
            canvas.width = options.width;
            canvas.height = options.height;
            ctx = canvas.getContext('2d');

            // compute tileW/tileH based on options.width/options.height
            tileW = options.width / qrcode.getModuleCount();
            tileH = options.height / qrcode.getModuleCount();

            // draw in the canvas
            for (row = 0; row < qrcode.getModuleCount(); row += 1) {
                for (col = 0; col < qrcode.getModuleCount(); col += 1) {
                    ctx.fillStyle = qrcode.isDark(row, col) ? options.foreground : options.background;
                    w = (Math.ceil((col + 1) * tileW) - Math.floor(col * tileW));
                    h = (Math.ceil((row + 1) * tileW) - Math.floor(row * tileW));
                    ctx.fillRect(Math.round(col * tileW), Math.round(row * tileH), w, h);
                }
            }
			
            // return just built canvas
            return canvas;
        }

        return this.each(function () {
            var element = create();
            jQuery(element).appendTo(this);
        });
    };
})(jQuery);