<!
DOCTYPE
html>
<
html
>
<
head
>
<
title
>Photo</
title
>
<
style
>
video {transform: rotateY(180deg);}
</
style
>
</
head
>
<
body
>
<
button
onclick="showCamera()">开启摄像头</
button
>
<
div
class="bg-content" style="display: none;">
<
div
class="show-photo">
<
video
id="video" width="600px" height="600px" autoplay="autoplay"></
video
>
<
canvas
id="canvas" width="600px" height="600px" style="display: none;"></
canvas
>
<
a
id="downloadA"></
a
>
</
div
>
<
div
class="take-photo">
<
button
type="button" onclick="takePhoto()">
拍照
</
button
>
</
div
>
<
div
class="close-photo">
<
button
type="button" onclick="closePhoto()">
关闭
</
button
>
</
div
>
</
div
>
<
script
type="text/javascript">
/**
* 开启摄像头
*/
let mediaStreamTrack = null; // 视频对象(全局)
function showCamera() {
$(".bg-content").css("display", "block");
let constraints = {
video: {width: 600, height: 600},
audio: true
};
//获得video摄像头区域
let video = document.getElementById("video");
//这里介绍新的方法,返回一个 Promise对象
// 这个Promise对象返回成功后的回调函数带一个 MediaStream 对象作为其参数
// then()是Promise对象里的方法
// then()方法是异步执行,当then()前的方法执行完后再执行then()内部的程序
// 避免数据没有获取到
let promise = navigator.mediaDevices.getUserMedia(constraints);
promise.then(function (MediaStream) {
mediaStreamTrack = typeof MediaStream.stop === 'function' ? MediaStream : MediaStream.getTracks()[1];
video.srcObject = MediaStream;
video.muted = true;
video.play();
});
}
/**
* 拍摄照片
*/
function takePhoto() {
let video = document.getElementById("video");
let canvas = document.getElementById("canvas");
let ctx = canvas.getContext('2d');
ctx.drawImage(video, 0,
ctx.translate(canvas.width, 0);
ctx.scale(-1, 1);、
let img = document.getElementById("canvas").toDataURL("image/png");
var triggerDownload = $("#downloadA").attr("href", img).attr("download", "micro-blog.png");
triggerDownload[0].click();
}
/**
* 关闭摄像头
*/
function closePhoto() {
mediaStreamTrack.stop();
$(".bg-content").css("display", "none");
}
</
script
>
</
body
>
</
html
>