是否可以替换基本64位编码图像中的颜色？

Question

有没有办法采用base 64字符串,例如:

.copyIcon {background: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAAW0lEQVR42mNgQALCi7//J4QZcAFiNOM1hJANBA0h1QC83iHFizDJ/dgww/7/LAQNwKUZbkjDfya8YQZXiCqJagilBmAzhLYGYDNsJBhAMD3gS854NS/6vg+fZgDKvmW19S7PRAAAAABJRU5ErkJggg==") center center no-repeat;}

用JavaScript替换另一种纯色的纯色？

在这个具体的例子中,我在icon(#13A3F7)中有一个纯色,我想用另一个纯色(#ff6400)代替.

这样做的原因是它不是一次性的.我希望能够通过设置将图标更改为任何颜色.

有什么方法可以做到这一点吗？

Answer 1

这是一个小功能,它有3个参数:data,colorFrom,colorTo(两种颜色应以十六进制提供)

function changeColInUri(data,colfrom,colto) {
    // create fake image to calculate height / width
    var img = document.createElement("img");
    img.src = data;
    img.style.visibility = "hidden";
    document.body.appendChild(img);

    var canvas = document.createElement("canvas");
    canvas.width = img.offsetWidth;
    canvas.height = img.offsetHeight;

    var ctx = canvas.getContext("2d");
    ctx.drawImage(img,0,0);

    // remove image
    img.parentNode.removeChild(img);

    // do actual color replacement
    var imageData = ctx.getImageData(0,0,canvas.width,canvas.height);
    var data = imageData.data;

    var rgbfrom = hexToRGB(colfrom);
    var rgbto = hexToRGB(colto);

    var r,g,b;
    for(var x = 0, len = data.length; x < len; x+=4) {
        r = data[x];
        g = data[x+1];
        b = data[x+2];

        if((r == rgbfrom.r) &&
           (g == rgbfrom.g) &&
           (b == rgbfrom.b)) {

            data[x] = rgbto.r;
            data[x+1] = rgbto.g;
            data[x+2] = rgbto.b;

        } 
    }

    ctx.putImageData(imageData,0,0);

    return canvas.toDataURL();
}

将十六进制颜色转换为RGB需要一个附加功能(正确匹配)

function hexToRGB(hexStr) {
    var col = {};
    col.r = parseInt(hexStr.substr(1,2),16);
    col.g = parseInt(hexStr.substr(3,2),16);
    col.b = parseInt(hexStr.substr(5,2),16);
    return col;
}

用法如下:

changeColInUri(
    "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAAW0lEQVR42mNgQALCi7//J4QZcAFiNOM1hJANBA0h1QC83iHFizDJ/dgww/7/LAQNwKUZbkjDfya8YQZXiCqJagilBmAzhLYGYDNsJBhAMD3gS854NS/6vg+fZgDKvmW19S7PRAAAAABJRU5ErkJggg==",
    "#13A3F7",
    "#ff6400"
);

它将返回一个新数据:image/png; 具有交换颜色的URI,这是最终结果的工作jsfiddle

http://jsfiddle.net/V5dU2/

(在Chrome,Firefox和IE10上测试过)