navigator.getUserMedia = navigator.getUserMedia ||  navigator.webkitGetUserMedia || navigator.mozGetUserMedia;// Callback to be called in case of success...function successCallback(gotStream) {video.src = http://www.mamicode.com/window.URL.createObjectURL(stream);"navigator.getUserMedia error: ", error);}// Constraints object for low resolution videovar qvgaConstraints = { video: {    mandatory: {      maxWidth: 320,      maxHeight: 240} }};// Constraints object for standard resolution videovar vgaConstraints = { video: {    mandatory: {      maxWidth: 640,      maxHeight: 480} }};// Constraints object for high resolution videovar hdConstraints = { video: {    mandatory: {      minWidth: 1280,      minHeight: 960} }};function getMedia(constraints){if (!!stream) { video.src = http://www.mamicode.com/null; stream.stop();>

  1 function call() {  2   log("Starting call");  3   4   // Note well: getVideoTracks() and getAudioTracks() are not currently supported in Firefox...  5   // ...just use them with Chrome  6   if (navigator.webkitGetUserMedia) {  7       // Log info about video and audio device in use  8       if (localStream.getVideoTracks().length > 0) {  9         log(‘Using video device: ‘ + localStream.getVideoTracks()[0].label); 10       } 11       if (localStream.getAudioTracks().length > 0) { 12         log(‘Using audio device: ‘ + localStream.getAudioTracks()[0].label); 13       } 14   } 15    16   // Chrome 17   if (navigator.webkitGetUserMedia) { 18       RTCPeerConnection = webkitRTCPeerConnection; 19   // Firefox 20   }else if(navigator.mozGetUserMedia){ 21       RTCPeerConnection = mozRTCPeerConnection; 22       RTCSessionDescription = mozRTCSessionDescription; 23       RTCIceCandidate = mozRTCIceCandidate; 24   } 25   log("RTCPeerConnection object: " + RTCPeerConnection); 26    27   // This is an optional configuration string, associated with NAT traversal setup 28   var servers = null; 29  30   // Create the local PeerConnection object 31   localPeerConnection = new RTCPeerConnection(servers); 32   log("Created local peer connection object localPeerConnection"); 33   // Add a handler associated with ICE protocol events 34   localPeerConnection.onicecandidate = gotLocalIceCandidate; 35  36   // Create the remote PeerConnection object 37   remotePeerConnection = new RTCPeerConnection(servers); 38   log("Created remote peer connection object remotePeerConnection"); 39   // Add a handler associated with ICE protocol events... 40   remotePeerConnection.onicecandidate = gotRemoteIceCandidate; 41   // ...and a second handler to be activated as soon as the remote stream becomes available  42   remotePeerConnection.onaddstream = gotRemoteStream; 43  44   // Add the local stream (as returned by getUserMedia() to the local PeerConnection 45   localPeerConnection.addStream(localStream); 46   log("Added localStream to localPeerConnection"); 47    48   // We‘re all set! Create an Offer to be ‘sent‘ to the callee as soon as the local SDP is ready 49   localPeerConnection.createOffer(gotLocalDescription, onSignalingError); 50 } 51  52 function onSignalingError(error) { 53     console.log(‘Failed to create signaling message : ‘ + error.name); 54 } 55  56 // Handler to be called when the ‘local‘ SDP becomes available 57 function gotLocalDescription(description){ 58   // Add the local description to the local PeerConnection 59   localPeerConnection.setLocalDescription(description); 60   log("Offer from localPeerConnection: \n" + description.sdp); 61    62   // ...do the same with the ‘pseudo-remote‘ PeerConnection 63   // Note well: this is the part that will have to be changed if you want the communicating peers to become 64   // remote (which calls for the setup of a proper signaling channel) 65   remotePeerConnection.setRemoteDescription(description); 66    67   // Create the Answer to the received Offer based on the ‘local‘ description 68   remotePeerConnection.createAnswer(gotRemoteDescription, onSignalingError); 69 } 70  71 // Handler to be called when the ‘remote‘ SDP becomes available 72 function gotRemoteDescription(description){ 73   // Set the ‘remote‘ description as the local description of the remote PeerConnection 74   remotePeerConnection.setLocalDescription(description); 75   log("Answer from remotePeerConnection: \n" + description.sdp); 76   // Conversely, set the ‘remote‘ description as the remote description of the local PeerConnection  77   localPeerConnection.setRemoteDescription(description); 78 } 79  80 // Handler to be called as soon as the remote stream becomes available 81 function gotRemoteStream(event){     82   // Associate the remote video element with the retrieved stream 83   if (window.URL) { 84       // Chrome 85       remoteVideo.src = http://www.mamicode.com/window.URL.createObjectURL(event.stream);> 86   } else { 87       // Firefox 88       remoteVideo.src = http://www.mamicode.com/event.stream;> 89   }   90   log("Received remote stream"); 91 } 92  93 // Handler to be called whenever a new local ICE candidate becomes available 94 function gotLocalIceCandidate(event){ 95   if (event.candidate) { 96     // Add candidate to the remote PeerConnection  97     remotePeerConnection.addIceCandidate(new RTCIceCandidate(event.candidate)); 98     log("Local ICE candidate: \n" + event.candidate.candidate); 99   }100 }101 102 // Handler to be called whenever a new ‘remote‘ ICE candidate becomes available103 function gotRemoteIceCandidate(event){104   if (event.candidate) {105     // Add candidate to the local PeerConnection      106     localPeerConnection.addIceCandidate(new RTCIceCandidate(event.candidate));107     log("Remote ICE candidate: \n " + event.candidate.candidate);108   }