效果图： 整体效果:
视频加载：
拍照：
第一步：创建HTML元素
首先，我们要创建一个HTML5的文档。
<!doctype html> <html> <head> <meta charset="utf-8"> <title>无标题文档</title> </head> <body> </body> </html>
然后在<body></body>插入以下代码：
<video id="video" width="640" height="480" autoplay></video> <button id="snap">截图</button> <canvas id="canvas" width="640" height="480"></canvas>
第二步：创建JavaScript
首先，要在<head></head>里创建一个JavaScript：
<script language="javascript">
// Grab elements, create settings, etc.
var video = document.getElementById('video');
// Get access to the camera!
if(navigator.mediaDevices && navigator.mediaDevices.getUserMedia) {
// Not adding `{ audio: true }` since we only want video now
navigator.mediaDevices.getUserMedia({ video: true }).then(function(stream) {
//video.src = window.URL.createObjectURL(stream);
video.srcObject = stream;
video.play();
});
}
/* Legacy code below: getUserMedia
else if(navigator.getUserMedia) { // Standard
navigator.getUserMedia({ video: true }, function(stream) {
video.src = stream;
video.play();
}, errBack);
} else if(navigator.webkitGetUserMedia) { // WebKit-prefixed
navigator.webkitGetUserMedia({ video: true }, function(stream){
video.src = window.webkitURL.createObjectURL(stream);
video.play();
}, errBack);
} else if(navigator.mozGetUserMedia) { // Mozilla-prefixed
navigator.mozGetUserMedia({ video: true }, function(stream){
video.srcObject = stream;
video.play();
}, errBack);
}
*/
</script>
随后，要在刚才创建的HTML元素的后面插入以下代码：
<script language="javascript">
// Elements for taking the snapshot
var canvas = document.getElementById('canvas');
var context = canvas.getContext('2d');
var video = document.getElementById('video');
// Trigger photo take
document.getElementById("snap").addEventListener("click", function() {
context.drawImage(video, 0, 0, 640, 480);
});
</script>
现在，这个HTML就可以完成打开摄像头，和拍照的功能了！