代码:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>将canvas获取的图片下载到本地</title>
</head>
<body>
<style>
video, canvas {
outline: 1px solid red;
}
</style>
<p>这里通过拍照来获取你的图像，然后将其下载到本地。如果开启摄像头时有提示，请点击允许</p>
<button onclick="startVideo()">点击启用摄像头</button>
<button onclick="Shoot()">点击拍照</button>
<button onclick="download()">点击下载</button>
<br>
<p>左侧是摄像头当前拍摄中区域，右侧图片是已拍摄的图像，下载的内容是右边已拍摄的图像</p>
<video width="640" height="480" autoplay></video>
<canvas width="640" height="480"></canvas>
<script>
var video = document.querySelector('video');
var canvas = document.querySelector('canvas');
//启用摄像头，开始拍摄
function startVideo() {
// video捕获摄像头画面
navigator.mediaDevices.getUserMedia({
video: true,
}).then(success).catch(error)
function success(stream) {
video.src = window.webkitURL.createObjectURL(stream);
video.play();
}
function error(err) {
alert('video error: ' + err)
}
}
function Shoot() {
var context = canvas.getContext('2d');
//把当前视频帧内容渲染到画布上
context.drawImage(self.video, 0, 0, 640, 480);
}
//将图片下载到本地
function download() {
var dom = document.createElement("a");
dom.href = this.canvas.toDataURL("image/png");
dom.download = new Date().getTime() + ".png";
dom.click();
}
</script>
</body>
</html>