图片转base64

html:

<img src="img1.png">

js:

 1  //海报转base64
 2                 function getBase64Image(img) {
 3                     var canvas = document.createElement("canvas");
 4                     canvas.width = img.width;
 5                     canvas.height = img.height;
 6                     var ctx = canvas.getContext("2d");
 7                     ctx.drawImage(img, 0, 0, img.width, img.height);
 8                     var ext = img.src.substring(img.src.lastIndexOf(".") + 1).toLowerCase();
 9                     var dataURL = canvas.toDataURL("image/" + ext);
10                     return dataURL;
11                 }
12 
13           var img = $("img").prop("src");
14                 var image = new Image();
15                 image.src = img;
16            var small_base64 = getBase64Image(image);