html5 更新圖片顏色示例代碼

 代碼如下:

<canvas id="c1" width="1220" height = "880" style="background: none repeat scroll 0% 0% transparent; "></canvas>
<script>
var cID = "c1";
var image = new Image();
image.src = "Eye/item_eye_1.png";
image.onload = function () {
recolorImage(cID,image, 0, 0, 0, 255, 0, 0);
}
function recolorImage(c,img, oldRed, oldGreen, oldBlue, newRed, newGreen, newBlue) {
var c = document.getElementById(c);
var ctx = c.getContext("2d");
var w = img.width;
var h = img.height;
c.width = w;
c.height = h;
// draw the image on the temporary canvas
ctx.drawImage(img, 0, 0, w, h);
// pull the entire image into an array of pixel data
var imageData = ctx.getImageData(0, 0, w, h);
// examine every pixel,
// change any old rgb to the new-rgb
for (var i = 0; i < imageData.data.length; i += 4) {
// is this pixel the old rgb?
if (imageData.data[i] == oldRed && imageData.data[i + 1] == oldGreen && imageData.data[i + 2] == oldBlue) {
// change to your new rgb
imageData.data[i] = newRed;
imageData.data[i + 1] = newGreen;
imageData.data[i + 2] = newBlue;
}
}
// put the altered data back on the canvas
ctx.putImageData(imageData, 0, 0);
}
</script>