//pokaz slajdów
$(document).ready( function(){

    $('#logo').innerfade({
        speed: 'slow',
        timeout: 15000,
        type: 'sequence',
        containerheight: '325px'
    });


    //$('#logo li').corner("round");
    //$('.thumb_gallery').corner("round");
    $('.category_thumb').corner("round");
    Cufon.replace('.logo');

    $('#present_list').liScroll({travelocity: 0.05});


} );

function GrayScale() {
    var canvas = document.createElement('canvas');
    var canvasContext = canvas.getContext('2d');
    var imgW = imgObj.width;
    var imgH = imgObj.height;
    canvas.width = imgW;
    canvas.height = imgH;
    canvasContext.drawImage(imgObj, 0, 0);
    var imgPixels = canvasContext.getImageData(0, 0, imgW, imgH);
    for(var y = 0; y < imgPixels.height; y++){
         for(var x = 0; x < imgPixels.width; x++){
              var i = (y * 4) * imgPixels.width + x * 4;
              var avg = (imgPixels.data[i] + imgPixels.data[i + 1] + imgPixels.data[i + 2]) / 3;
              imgPixels.data[i] = avg;
              imgPixels.data[i + 1] = avg;
              imgPixels.data[i + 2] = avg;
         }
    }
    canvasContext.putImageData(imgPixels, 0, 0, 0, 0, imgPixels.width, imgPixels.height);
    return canvas.toDataURL();

}