GIF图片分解和合成

[hankliu62]

• https://github.com/jnordberg/gif.js 合并GIF
• https://github.com/antimatter15/jsgif 分解GIF
• https://article.juejin.cn/post/7170221606415892511 打包下载
• https://github.com/renzhezhilu/gifsicle-wasm-browser 压缩GIF

案例

• https://tools.kalvinbg.cn/image/gif2img

分解GIF

import SuperGif from 'libgif'

var file = e.target.files[0];
 console.log(file.type.indexOf('image/gif'));
 load_gif(file);
function load_gif(gif_source) {
  var gifImg = document.getElementById('gifImg');
  // gif库需要img标签配置下面两个属性
  gifImg.setAttribute('rel:animated_src', URL.createObjectURL(gif_source))
  gifImg.setAttribute('rel:auto_play', '0')
  
  // 新建gif实例
  var rub = new SuperGif({ gif: gifImg } );
  
  var running = false;
  rub.load(function(){
  var img_list = [];
  var j = 0;
  console.log(rub.get_length());
  for (var i=1; i <= rub.get_length(); i++) {
  // 遍历gif实例的每一帧
  rub.move_to(i);
  
  var imgImage = new Image();
  //canvas生成base64图片数据
  imgImage.src = rub.get_canvas().toDataURL('image/jpeg',0.8);
  }
 }

图片合成

import GIF from 'gif.js'
var gif = new GIF({
  workers: 2,
  quality: 10,
  workerScript: 'js/gif.worker.js'
});
var j = 0;
  
var canvas= document.createElement("canvas");
var ctx = tCanvas.getContext('2d');
  
for (var i=1; i <= len; i++) {
  
 var imgImage = new Image();
 imgImage.src = img;
 imgImage.onload = function (e) {
  
 //Canvas绘制图片
 canvas.width = width;
 canvas.height = height;
 console.log(width,height)
 //铺底色
 ctx.fillStyle = "#fff";
 ctx.fillRect(0, 0, canvas.width, canvas.height);
 ctx.drawImage(imgImage, 0, 0, width, height);
  
  
 gif.addFrame(canvas,{copy:true,delay:50});
 j++;
 //图片
 if(j>=len) {
 gif.render()
 };
 }
}
gif.on('finished', function(blob) {
 //生成图片链接
  var url = URL.createObjectURL(blob);
}