写一个简易的HTML网页，其中JS读取本地H264文件，并可以像ffplay一样将其播放到网页上-Go服务器开发

下面是一个简易的HTML网页示例，其中使用JavaScript读取本地H264文件，并通过canvas元素将其播放到网页上：

<!DOCTYPE html>
<html>
<head>
    <title>播放H264文件</title>
</head>
<body>
    <canvas id="videoCanvas"></canvas>
    <script>
        // 创建视频元素
        var video = document.createElement('video');
        video.autoplay = true;
        
        // 创建画布元素
        var canvas = document.getElementById('videoCanvas');
        var context = canvas.getContext('2d');
        // 读取本地H264文件
        function readH264File(file) {
            var reader = new FileReader();
            reader.onload = function(e) {
                playH264File(new Uint8Array(e.target.result));
            }
            reader.readAsArrayBuffer(file);
        }
        // 解析并播放H264文件
        function playH264File(data) {
            var codec = new Module.Codec();
            
            codec.onPictureDecoded = function(y, u, v, width, height) {
                context.clearRect(0, 0, canvas.width, canvas.height);
                context.drawImage(yuv420ToCanvas(y, u, v, width, height), 0, 0);
                
                codec.decode();
            };
            codec.init(canvas.width, canvas.height);
            for (var i = 0; i < data.length; i++) {
                codec.appendFrame(data[i]);
            }
            
            codec.decode();
        }
        // YUV420转换为Canvas图像数据
        function yuv420ToCanvas(yData, uData, vData, width , height){
            var canvasTmpY = document.createElement("canvas");
		    var ctxY       = canvasTmpY.getContext("2d");
		    var imageDataY = ctxY.createImageData(width, height);
		    for (var i=0;i<yData.length;i++)
		        imageDataY.data[i]=yData[i];
            canvasTmpY.width  = width;
            canvasTmpY.height = height;
            ctxY.putImageData(imageDataY,0,0);
            var canvasTmpU = document.createElement("canvas");
		    var ctxU       = canvasTmpU.getContext("2d");
		    var imageDataU = ctxU.createImageData(width / 2, height / 2);
		    for (var i=0;i<uData.length;i++)
		        imageDataU.data[i]=uData[i];
            canvasTmpU.width  = width / 2;
            canvasTmpU.height = height / 2;
            ctxU.putImageData(imageDataU,0,0);
             var canvasTmpV = document.createElement("canvas");
		     var ctxV       = canvasTmpV.getContext("2d");
		     var imageDataV = ctxV.createImageData(width / 2 , height / 2 );
		     for (var i=0;i<vData.length;i++)
		         imageDataV.data[i]=vData[i];
             canvasTmpV.width  = width / 2 ;
             canvasTmpV.height = height / 2 ;
             ctxV.putImageData(imageDataV,0,0);
	         // 将 YUV420 转换为 RGB
             yuvToRgb(canvas.width ,canvas.height ,
                     [canvasTmpY ,canvasTmpU ,canvasTmpV ],
                     [ctxY        ,ctxU        ,ctxV ]);
		      return createRGBImageFrom3Canvas(canvas.width ,canvas.height,
                                        [canvasTmpY ,canvasTmpU ,canvasTmpV ]);
        }
		function yuvToRgb(width,height,yuvArray,cavansArray){
			var tmpArr=[];
			for(var j=0;j<height;j++){
				for(var i=0;i<width;i++){
					var Y = yuvArray[0].getContext("2d").getImageData(i,j,1,1).data[0] -16;
					var U = yuvArray[1].getContext("2d").getImageData(i/2,j/2,1,1).data[0] - 128;
					var V = yuvArray[2].getContext("2d").getImageData(i/2,j/2,1,1).data[0] - 128;
                    var R = (Y + 1.402 * V);
                    var G = (Y - 0.344 * U - 0.714 * V);
                    var B = (Y + 1.772 * U);
		            if(R<0)R=0;if(R>255)R=255;
		            if(G<0)G=0;if(G>255)G=255;
		            if(B<0)B=0;if(B>255)B=255;
				    tmpArr.push([parseInt(R),parseInt(G),parseInt(B)]);
		        }
	        }
            for(var j=0;j<height;j++)
			    for(var i=0;i<width;i++){
			        cavansArray.getContext("2d")
			                  .fillStyle="rgb("+tmpArr[i+j*width][0]+","
											 +tmpArr[i+j*width][1]+","
											 +tmpArr[i+j*width][2]+")";
			    	cavansArray.getContext("2d")
			    		      .fillRect( i ,j , 4 ,4 );
	        }
        }
		function createRGBImageFrom3Canvas(width,height,cavansArray){
			var canvasTmp     = document.createElement("canvas");
		    var ctxTmp        = canvasTmp.getContext('2d');
		    canvasTmp.width   = width ;
		    canvasTmp.height  = height;
		    var imageDataTmp = ctxTmp.createImageData(width, height);
		    for (var j=0;j<height;j++){
		        for(var i=0;i<width;i++){
		            imageDataTmp.data[4*(i+j*width)  ]=cavansArray[0].getContext("2d").getImageData(i,j,1,1).data[0];
		            imageDataTmp.data[4*(i+j*width)+1]=cavansArray[0].getContext("2d").getImageData(i,j,1,1).data[1];
		            imageDataTmp.data[4*(i+j*width)+2]=cavansArray[0].getContext("2d").getImageData(i,j,1,1).data[2];
		            imageDataTmp.data[4*(i+j*width)+3]=255;
		        }
		    }
	        ctxTmp.putImageData(imageDataTmp , 0 , 0 );
	    	return canvasTmp
		}
        // 监听文件选择事件
        document.querySelector('input[type="file"]').addEventListener('change', function(e) {
            var file = e.target.files[0];
            readH264File(file);
        });
    </script>
    <input type="file" accept=".h264">
</body>
</html>