1.input的change事件可以拿到event.target.files
2.读取文件
let reader = new FileReader();reader.readAsDataURL(img);
3.在reader.onload里面可以拿到e.target.result
4.读取图片
let image = new Image(); image.src = e.target.result;
5.在image.onload里面可以设置canvas
this.context.drawImage(image, 0, 0, this.imageWidth, this.imageHeight);
6.获取canvas的图片算相似度
let imageData = this.context.getImageData(0, 0, this.imageWidth, this.imageHeight);
7.canvas转base64
this.canvasSrc = this.canvas.toDataURL("image/png");
8.base64转png
