Canvas与Image互转

function fImageToCanvas(image){
　　var oCanvas = document.createElement("canvas");
　　oCanvas.width = image.width;
　　oCanvas.height = image.height;
　　oCanvas.getContext("2d").drawImage(image,0,0);
　　return oCanvas;
}

function fCanvasToImage(canvas){
　　var oImage = new Image();
　　image.src = canvas.toDataURL("image/png");
　　return image;
}

参考：http://blog.csdn.net/renfufei/article/details/9855519