html5worker实例(二)图片变换效果_html5教程技巧

onmessage = function(e) {
postMessage(filter(e.data))
};
function filter(imgd) {
var pix = imgd.pixels.data;
var xcord = imgd.x / 1000;
var ycord = imgd.y / 1000;
for ( var i = 0, n = pix.length; i < n; i += 4) {
var grayscale = pix[i] * xcord + pix[i + 1] * .59 + pix[i + 2] * .11;
pix[i] = grayscale; // red
pix[i + 1] = grayscale; // green
pix[i + 2] = grayscale; // blue
}
imgd['pixels'].data = pix;
return imgd;
}