canvas调节视频颜色

 <!DOCTYPE html>

 <html lang="en">

 <head>

     <meta charset="UTF-8">

     <title>Title</title>

 </head>

 <body>

 <canvas id="canvas" width="400" height="300"></canvas>

 <script src="main.js"></script>

 </body>

 </html>

 (function () {

     var videoWidth = 320;

     var videoHeight = 240;

     var canvas = document.getElementById("canvas");

     var memoryCanvas = document.createElement("canvas");

     memoryCanvas.width = 400;

     memoryCanvas.height = 300;

     var context = canvas.getContext("2d");

     var memoryContext = memoryCanvas.getContext("2d");

     var targetBitmap = memoryContext.createImageData(videoWidth, videoHeight);

     /**

      * @type {HTMLVideoElement}

      */

     var video;

     function loadVideo() {

         video = document.createElement("video");

         video.autoplay = true;

         video.src = "12.mp4";

     }

     function render() {

         // context.drawImage(video, 0, 0);

         memoryContext.drawImage(video, 0, 0);

         var sourceImageData = memoryContext.getImageData(0, 0, videoWidth, videoHeight);

         for (var i = 0; i < sourceImageData.data.length; i += 4) {

             var r = sourceImageData.data[i];

             var g = sourceImageData.data[i + 1];

             var b = sourceImageData.data[i + 2];

             var c = (r + g + b) / 3;

             targetBitmap.data[i] = c;

             targetBitmap.data[i + 1] = c;

             targetBitmap.data[i + 2] = c;

             targetBitmap.data[i + 3] = 255;

         }

         context.putImageData(targetBitmap, 0, 0);

         requestAnimationFrame(render);

     }

     function init() {

         loadVideo();

         render();

     }

     init();

 })();

巴特西

canvas调节视频颜色

最新文章

热门文章