getUserMedia-multiple-camera/index.html at main · DogPo/getUserMedia-multiple-camera · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Multiple Camera Simple Example</title>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=no">
    <style>
    </style>
  </head>
  <body>
    <div>
      <label>
        Camera 1:
        <select id="select-camera-1"></select>
      </label>
      <label>
        Camera 2:
        <select id="select-camera-2"></select>
      </label>
    </div>
    <div>
      <video id="camera1" controls autoplay playsinline></video>
    </div>
    <div>
      <video id="camera2" controls autoplay playsinline></video>
    </div>
    <button id="btn-open-camera">Open Cameras</button>
    <script>
      var devices;
      var camSelect1 = document.getElementById("select-camera-1");
      var camSelect2 = document.getElementById("select-camera-2");
      window.onload = async function(){
        await listDevices()
      }

      async function listDevices(){
        devices = await getCameraDevices()
        for (let index = 0; index < devices.length; index++) {
          const device = devices[index];
          camSelect1.appendChild(new Option(device.label ?? "Camera "+index,device.deviceId));
          camSelect2.appendChild(new Option(device.label ?? "Camera "+index,device.deviceId));
        }
        camSelect2.selectedIndex = 1;
      }

      async function getCameraDevices(){
        await askForPermissions();
        var allDevices = await navigator.mediaDevices.enumerateDevices();
        var cameraDevices = [];
        for (var i=0;i<allDevices.length;i++){
          var device = allDevices[i];
          if (device.kind == 'videoinput'){
            cameraDevices.push(device);
          }
        }
        return cameraDevices;
      }

      async function askForPermissions(){
        var stream;
        try {
          var constraints = {video: true, audio: false}; //ask for camera permission
          stream = await navigator.mediaDevices.getUserMedia(constraints);
        } catch (error) {
          console.log(error);
        }
        closeStream(stream);
      }

      function closeStream(stream){
        try{
          if (stream){
            stream.getTracks().forEach(track => track.stop());
          }
        } catch (e){
          alert(e.message);
        }
      }

      document.getElementById("btn-open-camera").addEventListener("click",function(){
        captureCamera(document.getElementById("camera1"),camSelect1.selectedOptions[0].value);
        captureCamera(document.getElementById("camera2"),camSelect2.selectedOptions[0].value);
      });

      function captureCamera(video, selectedCamera) {
        var constraints = {
          audio:false,
          video:true
        }
        if (selectedCamera) {
          constraints = {
            video: {deviceId: selectedCamera},
            audio: false
          }
        }
        navigator.mediaDevices.getUserMedia(constraints).then(function(camera) {
          video.srcObject = camera;
        }).catch(function(error) {
          alert('Unable to capture your camera. Please check console logs.');
          console.error(error);
        });
      }
    </script>
  </body>
</html>