在chrome中，呼叫本地攝像頭
阿新 • • 發佈：2018-11-15
原文地址：https://blog.csdn.net/journey191/article/details/40744015
<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>HTML5 GetUserMedia Demo</title> <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0" />在chrome中呼叫本地攝像頭</head> <body> <input type="button" title="開啟攝像頭" value="開啟攝像頭" onclick="getMedia();" /><br /> <video height="120px" autoplay="autoplay"></video><hr /> <input type="button" title="拍照" value="拍照" onclick="getPhoto();" /><br /> <canvasid="canvas1" height="120px" ></canvas><hr /> <input type="button" title="視訊" value="視訊" onclick="getVedio();" /><br /> <canvas id="canvas2" height="120px"></canvas> <script type="text/javascript"> var video = document.querySelector('video');var audio, audioType; var canvas1 = document.getElementById('canvas1'); var context1 = canvas1.getContext('2d'); var canvas2 = document.getElementById('canvas2'); var context2 = canvas2.getContext('2d'); navigator.getUserMedia = navigator.getUserMedia || navigator.webkitGetUserMedia || navigator.mozGetUserMedia || navigator.msGetUserMedia; window.URL = window.URL || window.webkitURL || window.mozURL || window.msURL; var exArray = []; //儲存裝置源ID MediaStreamTrack.getSources(function (sourceInfos) { for (var i = 0; i != sourceInfos.length; ++i) { var sourceInfo = sourceInfos[i]; //這裡會遍歷audio,video，所以要加以區分 if (sourceInfo.kind === 'video') { exArray.push(sourceInfo.id); } } }); function getMedia() { if (navigator.getUserMedia) { navigator.getUserMedia({ 'video': { 'optional': [{ 'sourceId': exArray[1] //0為前置攝像頭，1為後置 }] }, 'audio':true }, successFunc, errorFunc); //success是獲取成功的回撥函式 } 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最初為null，而不是未定義的，我們可以靠這個來檢測Firefox的支援 video.mozSrcObject = stream; } else { video.src = window.URL && window.URL.createObjectURL(stream) || stream; } //video.play(); // 音訊 audio = new Audio(); audioType = getAudioType(audio); if (audioType) { audio.src = 'polaroid.' + audioType; audio.play(); } } function errorFunc(e) { alert('Error！'+e); } // 將視訊幀繪製到Canvas物件上,Canvas每60ms切換幀，形成肉眼視訊效果 function drawVideoAtCanvas(video,context) { window.setInterval(function () { context.drawImage(video, 0, 0,90,120); }, 60); } //獲取音訊格式 function getAudioType(element) { if (element.canPlayType) { if (element.canPlayType('audio/mp4; codecs="mp4a.40.5"') !== '') { return ('aac'); } else if (element.canPlayType('audio/ogg; codecs="vorbis"') !== '') { return ("ogg"); } } return false; } // vedio播放時觸發，繪製vedio幀影象到canvas // video.addEventListener('play', function () { // drawVideoAtCanvas(video, context2); // }, false); //拍照 function getPhoto() { context1.drawImage(video, 0, 0,90,120); //將video物件內指定的區域捕捉繪製到畫布上指定的區域，實現拍照。 } //視訊 function getVedio() { drawVideoAtCanvas(video, context2); } </script> </body> </html>