在学习h5的时候,canvas标签中getImageData()报错:security error!
具体代码如下(chrome浏览器):
var c=ctx.getImageData(0,img.width,img.height);
for(var i=0;i<c.height;i++){
for(var j=0;j<c.width;j++){
var x=(i4)c.height+(j*4);
var r=c.data[x];
var g=c.data[x+1];
var b=c.data[x+2];
c.data[x]=c.data[x+1]=c.data[x+2]=(r+g+b)/3;
for(var i=0;i<c.height;i++){
for(var j=0;j<c.width;j++){
var x=(i4)c.height+(j*4);
var r=c.data[x];
var g=c.data[x+1];
var b=c.data[x+2];
c.data[x]=c.data[x+1]=c.data[x+2]=(r+g+b)/3;
}
}
ctx.putImageData(c,c.width,c.height);
return canvas.toDataURL();
}
报错信息如下:Uncaught SecurityError: Failed to execute 'getImageData' on 'CanvasRenderingContext2D': The canvas has been tainted by cross-origin data.