调用本地摄像头使用HTML5 Canvas拍照并转为base64格式的图片
利用navigator对象
navigator.mediaDevices.getUserMedia({ audio:true, video:true })
说明：
navigator.mediaDevices.getUserMedia({
audio: false, video: true
}).then(function (result) {
video.srcObject = result;
})
h5利用canvas摄像拍照及转成base64格式，完成例子代码见下：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>调用本地摄像头使用HTML5 Canvas拍照并转为base64格式的图片</title>
</head>
<body>
<video muted autoplay='autoplay' id='video'></video>
<canvas id="canvas4" width="484px" height="484px" hidden></canvas>
<button id='control'>拍照</button>
<script>
var video = document.getElementById('video');
var audio, audioType;
var canvas4 = document.getElementById('canvas4');
var context4 = canvas4.getContext('2d');
navigator.getUserMedia = navigator.getUserMedia || navigator.webkitGetUserMedia || navigator.mozGetUserMedia || navigator.msGetUserMedia || navigator.mediaDevices;
window.URL = window.URL || window.webkitURL || window.mozURL || window.msURL;
// var exArray = []; //存储设备源ID
// MediaStreamTrack.getSources(function (sourceInfos) {
// for (var i = 0; i != sourceInfos.length; ++i) {
// var sourceInfo = sourceInfos[i];
// //这里会遍历audio,video，所以要加以区分
// if (sourceInfo.kind === 'video') {
// exArray.push(sourceInfo.id);
// }
// }
// });
function getMedia(){
if (navigator.getUserMedia) {
navigator.getUserMedia({
'video': true,
}, successFunc, errorFunc); //success是获取成功的回调函数
}
else {
alert('Native device media streaming (getUserMedia) not supported in this browser.');
}
}
function successFunc(stream) {
//alert('Succeed to get media!');
if (video.mozSrcObject !== undefined) {
//Firefox中，video.mozSrcObject最初为null，而不是未定义的，我们可以靠这个来检测Firefox的支持
video.mozSrcObject = stream;
}
else {
video.srcObject = stream;
// video.src = window.URL && window.URL.createObjectURL(stream) || stream;
}
}
function errorFunc(e) {
alert('Error！' + e);
}
// 将视频帧绘制到Canvas对象上,Canvas每60ms切换帧，形成肉眼视频效果
function drawVideoAtCanvas(video, context) {
window.setInterval(function () {
context.drawImage(video, 0, 0, 800, 600);
}, 60);
}
//拍照
function getPhoto() {
context4.drawImage(video, 0, 0, 484 ,484); //将video对象内指定的区域捕捉绘制到画布上指定的区域，实现拍照。
var new_img = document.createElement('img');
new_img.setAttribute('crossOrigin', 'anonymous');
new_img.src = canvas4.toDataURL("image/jpeg");//图片转为base64格式
new_img.setAttribute('width',300)
new_img.setAttribute('height',300)
console.log(canvas4.toDataURL("image/jpeg"))
document.body.appendChild(new_img)
}
getMedia()
control.addEventListener('click',function(){
getPhoto()
// drawVideoAtCanvas()
})
</script>
</body>
</html>
效果截图：
自拍照想想还是删了。。。
结束。
参考自：https://blog.csdn.net/qq_40678503/article/details/96318365
例子代码亲测可用。
