html5 更新图片颜色

<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>