canvas 跨域

DOMException: Failed to execute 'toDataURL' 
on 'HTMLCanvasElement': Tainted canvases may not be exported.
at convertCanvasToImage 

  this.state.image.setAttribute("crossOrigin",'Anonymous')
        this.state.image.src = "http://p7whtc26y.bkt.clouddn.com/18-4-29/34552105.jpg";