关于移动端在canvas中播放视频

Question

1.已经在pc上实现了在canvas中播放video标签的视频，现在在手机上进行测试，发现无法播放了2.` var fps = 1000/30; // 1/30秒var videoObj = document.getElementById("sec4-video");var canvasObj = document.getElementById("sec4-canvas"); var ctx=canvasObj.getContext('2d'); videoObj.addEventListener('play', function() {    var i=window.setInterval(function() {         ctx.drawImage(videoObj,0,0,400,400);},fps); },true);`<div class="slide-wrap">                <video autoplay loop   id="sec4-video">                     <source src="video/world-home-flat.mp4" type="video/mp4">                 </video>                 <canvas id="sec4-canvas" width="400" height="400"></canvas>             </div>