canvas todataurl()跨域报错

Question

客户端在new Image的时候已经设置了img.crossOrigin = 'Anonymous'，src是图片服务器上的图片地址，
drawImage和fillText之后调用todataurl，浏览器报错，转出来的dataURL不带图片，只有文字。服务端那边同事说服务端已经允许跨域，是哪里出了问题呢，该怎么解决？

Access to Image at 'http://cdn.img.mj188.com.cn/2,033c64c3a725.jpg' from origin 'http://weixin.mj188.com.cn' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://weixin.mj188.com.cn' is therefore not allowed access.