如何从WebRTC中获取当前图片作为图像？

// 获取视频流
navigator.mediaDevices.getUserMedia({ video: true })
  .then(function(stream) {
    // 创建画布
    var canvas = document.createElement('canvas');
    document.body.appendChild(canvas);
    
    // 绘制视频帧
    var context = canvas.getContext('2d');
    var video = document.createElement('video');
    video.srcObject = stream;
    video.addEventListener('play', function() {
      context.drawImage(video, 0, 0, canvas.width, canvas.height);
      
      // 获取图像数据
      var imageData = canvas.toDataURL();
      
      // 在此处进行图像数据的处理或传输
    });
    video.play();
  })
  .catch(function(error) {
    console.error('Error accessing video stream:', error);
  });