将 poster="placeholder.png"添加到 video 标记中。

<video width="470" height="255" poster="placeholder.png" controls>
<source src="video.mp4" type="video/mp4">
<source src="video.ogg" type="video/ogg">
<source src="video.webm" type="video/webm">
<object data="video.mp4" width="470" height="255">
<embed src="video.swf" width="470" height="255">
</object>
</video>

有用吗？

这似乎是一个额外的图像显示在那里。

你可以试试用这个

<img src="/images/image_of_video.png" alt="image" />
/* write your code for the video here */

现在使用 jQuery 播放视频并将图像隐藏为

$('img').click(function () {
$(this).hide();
// use the parameters to play the video now..
})

我从你的例子和其他例子中找到了解决方案，并且做了这个:

<video id="video1" width="470" height="264"  poster="video_poster.jpg" onclick="playPause()">
<source src="video.mp4" width="470" height="264" type="video/mp4" >
<source src="video.webm" type="video/webm" >
<source src="video.ogv" type="video/ogg" >
<object id="FlashID" classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" width="470" height="264" >
<param name="movie" value="video.swf" >
<param name="quality" value="high">
<param name="wmode" value="opaque">
<param name="swfversion" value="11.0.0.0">
<!-- This param tag prompts users with Flash Player 6.0 r65 and higher to download the latest version of Flash Player. Delete it if you don’t want users to see the prompt. -->
<param name="expressinstall" value="../../Scripts/expressInstall.swf">
<!-- Next object tag is for non-IE browsers. So hide it from IE using IECC. -->
<!--[if !IE]>-->
<object type="application/x-shockwave-flash" data="video.swf" width="500" height="500">
<!--<![endif]-->
<param name="quality" value="high">
<param name="wmode" value="opaque">
<param name="swfversion" value="11.0.0.0">
<param name="expressinstall" value="../../Scripts/expressInstall.swf">
<!-- The browser displays the following alternative content for users with Flash Player 6.0 and older. -->
<div>
<h4>Content on this page requires a newer version of Adobe Flash Player.</h4>
<p><a href="http://www.adobe.com/go/getflashplayer"><img src="http://www.adobe.com/images/shared/download_buttons/get_flash_player.gif" alt="Get Adobe Flash player" width="112" height="33" /></a></p>
</div>
<!--[if !IE]>-->
</object>
<!--<![endif]-->
Unfortunately Your browser is old and does not support full video experience.
</object>




</video>
<script>
var myVideo=document.getElementById("video1");
var att=document.createAttribute("poster");
if (myVideo.error) {
switch (myVideo.error.code) {
case MEDIA_ERR_NETWORK:alert("Network error - please try again later.");break;
case MEDIA_ERR_DECODE:alert("Video is broken.."); break;
case MEDIA_ERR_SRC_NOT_SUPPORTED:alert("Sorry, your browser can't play this video."); break;
}
}
else
{
function playPause()
{
if (myVideo.paused)
{
myVideo.play();
att.value="";
myVideo.setAttributeNode(att);
}
else myVideo.pause();
}
}
</script>

干得漂亮，谢谢！

如果您希望将视频第一帧作为缩略图，那么可以使用

Add #t=0.1 to your video source, like below


<video width="320" height="240" controls>
<source src="video.mp4#t=0.1" type="video/mp4">
</video>

注意: 确保您的视频类型(例如: mp4，ogg，webm 等)

将视频第一帧显示为缩略图:

将 preload="metadata"加入到你的 视频标签，将第一帧 #t=0.5的第二帧加入到你的 视频源:

<video width="400" controls="controls" preload="metadata">
<source src="https://www.w3schools.com/html/mov_bbb.mp4#t=0.5" type="video/mp4">
</video>

<?php
$thumbs_dir = 'E:/xampp/htdocs/uploads/thumbs/';
$videos = array();
if (isset($_POST["name"])) {
if (!preg_match('/data:([^;]*);base64,(.*)/', $_POST['data'], $matches)) {
die("error");
}
$data = $matches[2];
$data = str_replace(' ', '+', $data);
$data = base64_decode($data);
$file = 'text.jpg';
$dataname = file_put_contents($thumbs_dir . $file, $data);
}
?>
//jscode
<script type="text/javascript">
var videos = <?= json_encode($videos); ?>;
var video = document.getElementById('video');
video.addEventListener('canplay', function () {
this.currentTime = this.duration / 2;
}, false);
var seek = true;
video.addEventListener('seeked', function () {
if (seek) {
getThumb();
}
}, false);


function getThumb() {
seek = false;
var filename = video.src;
var w = video.videoWidth;//video.videoWidth * scaleFactor;
var h = video.videoHeight;//video.videoHeight * scaleFactor;
var canvas = document.createElement('canvas');
canvas.width = w;
canvas.height = h;
var ctx = canvas.getContext('2d');
ctx.drawImage(video, 0, 0, w, h);
var data = canvas.toDataURL("image/jpg");
var xmlhttp = new XMLHttpRequest;
xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
}
}
xmlhttp.open("POST", location.href, true);
xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xmlhttp.send('name=' + encodeURIComponent(filename) + '&data=' + data);
}
function failed(e) {
// video playback failed - show a message saying why
switch (e.target.error.code) {
case e.target.error.MEDIA_ERR_ABORTED:
console.log('You aborted the video playback.');
break;
case e.target.error.MEDIA_ERR_NETWORK:
console.log('A network error caused the video download to fail part-way.');
break;
case e.target.error.MEDIA_ERR_DECODE:
console.log('The video playback was aborted due to a corruption problem or because the video used features your browser did not support.');
break;
case e.target.error.MEDIA_ERR_SRC_NOT_SUPPORTED:
console.log('The video could not be loaded, either because the server or network failed or because the format is not supported.');
break;
default:
console.log('An unknown error occurred.');
break;
}




}
</script>
//Html
<div>
<video   id="video" src="1499752288.mp4" autoplay="true"  onerror="failed(event)" controls="controls" preload="none"></video>
</div>

1)添加以下 jquery:

$thumbnail.on('click', function(e){
e.preventDefault();
src = src+'&autoplay=1'; // src: the original URL for embedding
$videoContainer.empty().append( $iframe.clone().attr({'src': src}) ); // $iframe: the original iframe for embedding
}
);

注意: 在第一个 src (如图所示)中添加原来的 youtube 链接。

2)按以下方式编辑 iframe 标签:

<iframe width="1280" height="720" src="https://www.youtube.com/embed/nfQHF87vY0s?autoplay=1" frameborder="0" allowfullscreen></iframe>

注意: 复制粘贴 youtube 视频 ID 后嵌入/在 iframe src。