HTML5视频 - 文件加载完成事件?

时间:2011-02-28 04:09:05

标签: javascript html5 video buffer preload

我需要检测视频文件何时完成加载。我想我应该使用progress->缓冲区,但在我的脑海里,我记得读到这是不可靠的。有更好的方法,还是这样安全?

注意,我将保留每个用户已完全下载的视频的localStorage缓存,因此我事先知道视频是否已加载,并且可能会绕过进度 - >缓冲区,如果这是一个坚持点。

提前致谢。

3 个答案:

答案 0 :(得分:20)

你可以绑定“缓冲”事件,但(至少在Chrome中)这样可以正常工作,除了它不会调用最后一个“缓冲”事件(即它会检测到90%...... 94%... 98%......但不会拨打100%)。

注意:最新版本的jQuery应该使用.prop()而不是.attr()

为了解决这个问题,我使用setInterval()每500毫秒检查一次缓冲区(其中$ html5Video是你的<video>元素:

var videoDuration = $html5Video.attr('duration');

var updateProgressBar = function(){
    if ($html5Video.attr('readyState')) {
        var buffered = $html5Video.attr("buffered").end(0);
        var percent = 100 * buffered / videoDuration;

        //Your code here

        //If finished buffering buffering quit calling it
        if (buffered >= videoDuration) {
                clearInterval(this.watchBuffer);
        }
    }
};
var watchBuffer = setInterval(updateProgressBar, 500);

答案 1 :(得分:3)

我遇到了同样的问题,并使用了附加到progress事件的计时器。这是一个黑客,但我没有看到任何其他方式这样做。 (我在Chome 10上测试了这个 - Windows)。

var video = document.getElementById('#example-video-element');
var timer = 0;
video.addEventListener('progress', function (e) {
    if (this.buffered.length > 0) {

        if (timer != 0) {
            clearTimeout(timer);
        }

        timer = setTimeout(function () {            
            if(parseInt(video.buffered.end() / video.duration * 100) == 100) {
                // video has loaded.... 
            };          
        }, 1500);

    }
}, false); 

这看起来像你想要采用的方法类型,但我想会为那些可能正在寻找快速代码示例的匿名用户发布一个示例= p
GJ

答案 2 :(得分:0)

这是一个使用Google's MDC-Web's mdc-linear-progress UI组件的充实实现。

&#13;
&#13;
var doc = document;
var bufferLengthDetector;
var linearProgress;
var mdc = window.mdc;
mdc.autoInit();
var video = doc.querySelector('video');

if(doc.getElementById("footer-progress")){
    linearProgress = mdc.linearProgress.MDCLinearProgress.attachTo(doc.getElementById("footer-progress"));
}

if(video){
    
    video.addEventListener('timeupdate', function() {
        var percent = Math.floor((100 / video.duration) * video.currentTime);
        linearProgress.progress = percent/100;
    }, false);
    
    video.addEventListener('progress', function() {
        var duration = video.duration;
        if (duration > 0) {
            bufferLengthDetector = setInterval(readBuffer, 500);
        }
    });
}

function readBuffer(){
    var percent = video.buffered.end(video.buffered.length - 1) / video.duration;
    if (percent >= .9) {
        linearProgress.buffer = 1;
        clearInterval(bufferLengthDetector);
    }
    else {
        linearProgress.buffer = percent;
    }
}
&#13;
html {
    height:100%;
}
body{
    margin: 0;
}

#footer-progress{
    position: fixed;
    bottom: 0;
    width: 100%;
    visibility: visible;
    opacity: 1;    
}

video {
    position: fixed;
    top: 50%;
    left: 50%;
    min-width: 100%;
    min-height: 100%;
    width: auto;
    height: auto;
    z-index: -100;
    transform: translateX(-50%) translateY(-50%);
    background: #212121;
    background-size: cover;
    transition: visibility 1s, opacity 1s linear;
    visibility: visible;
    opacity: 1;
}
&#13;
<head>
<link rel="stylesheet" href="https://unpkg.com/material-components-web@latest/dist/material-components-web.min.css">
<script src="https://unpkg.com/material-components-web@latest/dist/material-components-web.min.js"></script>
</head>

<body>

    <video class="bg-video" playsinline autoplay>
        <source src="//rack.pub/media/do-not.webm" type="video/webm">
        <source src="//rack.pub/media/do-not.mp4" type="video/mp4">            
        I'm sorry your browser doesn't support HTML5 video in WebM with VP8/VP9 or MP4 with H.264.
    </video>
    
    <div role="progressbar" class="mdc-linear-progress" data-buffer="true" id="footer-progress">
        <div class="mdc-linear-progress__buffering-dots"></div>
        <div class="mdc-linear-progress__buffer"></div>
        <div class="mdc-linear-progress__bar mdc-linear-progress__primary-bar">
            <span class="mdc-linear-progress__bar-inner"></span>
        </div>
        <div class="mdc-linear-progress__bar mdc-linear-progress__secondary-bar">
            <span class="mdc-linear-progress__bar-inner"></span>
        </div>
    </div>  

</body>
&#13;
&#13;
&#13;