# 纯启动摄像头：

        使用摄像头            function accessCamera() {            const video = document.getElementById("video");            // 创建一个媒体流请求对象            const constraints = {                video: true,                audio: false            };            // 使用getUserMedia方法访问摄像头            navigator.mediaDevices.getUserMedia(constraints)                .then(function(stream) {                    // 将视频流赋值给video元素的src属性，以显示摄像头的视频                    video.srcObject = stream;                    video.onloadedmetadata = function(e) {                        video.play();                    };                })                .catch(function(error) {                    console.error("访问摄像头失败：", error);                });        }    
使用摄像头
访问摄像头

启动摄像头并拍照保存本地：

        使用摄像头            function accessCamera() {            const video = document.getElementById("video");            // 创建一个媒体流请求对象            const constraints = { video: true, audio: false };            // 使用getUserMedia方法访问摄像头            navigator.mediaDevices.getUserMedia(constraints)                .then(function(stream) {                    // 将视频流赋值给video元素的src属性，以显示摄像头的视频                    video.srcObject = stream;                    video.onloadedmetadata = function(e) {                        video.play();                    };                })                .catch(function(error) {                    console.error("访问摄像头失败：", error);                });        }        function takePhoto() {            const video = document.getElementById("video");            // 使用canvas捕获图像数据            const canvas = document.createElement("canvas");            canvas.width = video.videoWidth;            canvas.height = video.videoHeight;            const ctx = canvas.getContext("2d");            ctx.drawImage(video, 0, 0);            // 将图像数据保存为图片文件            const dataUrl = canvas.toDataURL();            saveAs(canvas.toDataURL(), "photo.jpg");        }        function saveAs(data, filename) {            const link = document.createElement("a");            link.href = data;            link.download = filename;            document.body.appendChild(link);            link.click();            document.body.removeChild(link);        }    
使用摄像头
访问摄像头拍照保存

 录制视频并保存：

      Video Recorder
Video Recorder
  Start Recording  Stop Recording    let mediaRecorder;  let recordedChunks = [];  const startButton = document.getElementById('startRecord');  const stopButton = document.getElementById('stopRecord');  const videoPlayer = document.getElementById('videoPlayer');  startButton.addEventListener('click', startRecording);  stopButton.addEventListener('click', stopRecording);  async function startRecording() {    const stream = await navigator.mediaDevices.getUserMedia({ video: true, audio: true });    mediaRecorder = new MediaRecorder(stream);    mediaRecorder.ondataavailable = function(event) {      if (event.data.size > 0) {        recordedChunks.push(event.data);      }    };    mediaRecorder.onstop = function() {      const blob = new Blob(recordedChunks, { type: 'video/webm' });      const url = URL.createObjectURL(blob);      videoPlayer.src = url;    };    mediaRecorder.start();    startButton.disabled = true;    stopButton.disabled = false;  }  function stopRecording() {    mediaRecorder.stop();    startButton.disabled = false;    stopButton.disabled = true;  }

共享屏幕和录频并保存在本地：

      Screen Recorder
Screen Recorder
  Start Recording  Stop Recording    Save Video  let mediaRecorder;  let recordedChunks = [];  const startButton = document.getElementById('startRecord');  const stopButton = document.getElementById('stopRecord');  const videoPlayer = document.getElementById('videoPlayer');  const saveButton = document.getElementById('saveVideo');  startButton.addEventListener('click', startRecording);  stopButton.addEventListener('click', stopRecording);  saveButton.addEventListener('click', saveVideo);  async function startRecording() {    const stream = await navigator.mediaDevices.getDisplayMedia({ video: true, audio: true });    mediaRecorder = new MediaRecorder(stream);    mediaRecorder.ondataavailable = function(event) {      if (event.data.size > 0) {        recordedChunks.push(event.data);      }    };    mediaRecorder.onstop = function() {      const blob = new Blob(recordedChunks, { type: 'video/mp4' });      const url = URL.createObjectURL(blob);      videoPlayer.src = url;    };    mediaRecorder.start();    startButton.disabled = true;    stopButton.disabled = false;  }  function stopRecording() {    mediaRecorder.stop();    startButton.disabled = false;    stopButton.disabled = true;  }  function saveVideo() {    const blob = new Blob(recordedChunks, { type: 'video/mp4' });    const url = URL.createObjectURL(blob);    const a = document.createElement('a');    a.href = url;    a.download = 'screen_recording.mp4';    const clickHandler = () => {      setTimeout(() => {        URL.revokeObjectURL(url);        a.removeEventListener('click', clickHandler);      }, 150);    };    a.addEventListener('click', clickHandler, false);    a.click();  }