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VideoCapturer switch camera

I am using a webrtc sample Code to stream from my Android device to a Webpage.
The sample Code does not have the function to Switch the camera. I tried to solve it but I failed. The sample uses a VideoCapturerAndroid class all of the Suggestions I found switching the camera used a different type.
The main part of the sample Looks like this:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_video_chat);
ButterKnife.bind(this);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
Bundle extras = getIntent().getExtras();
if (extras == null || !extras.containsKey(Constants.USER_NAME)) {
Intent intent = new Intent(this, MainActivity.class);
startActivity(intent);
Toast.makeText(this, "Need to pass username to VideoChatActivity in intent extras (Constants.USER_NAME).", Toast.LENGTH_SHORT).show();
finish();
return;
}
this.username = extras.getString(Constants.USER_NAME, "");
this.mCallStatus = (TextView) findViewById(R.id.call_status);
// First, we initiate the PeerConnectionFactory with our application context and some options.
PeerConnectionFactory.initializeAndroidGlobals(
this, // Context
true, // Audio Enabled
true, // Video Enabled
true, // Hardware Acceleration Enabled
null); // Render EGL Context
pcFactory = new PeerConnectionFactory();
this.pnRTCClient = new PnRTCClient(Constants.PUB_KEY, Constants.SUB_KEY, this.username);
List<PeerConnection.IceServer> servers = getXirSysIceServers();
if (!servers.isEmpty()) {
this.pnRTCClient.setSignalParams(new de.kevingleason.pnwebrtc.PnSignalingParams());
}
backFacingCam = VideoCapturerAndroid.getNameOfBackFacingDevice();
frontFacingCam = VideoCapturerAndroid.getNameOfFrontFacingDevice();
// Creates a VideoCapturerAndroid instance for the device name
//VideoCapturer capturer = VideoCapturerAndroid.create(frontFacingCam);
capturer = VideoCapturerAndroid.create(facingCam);
// First create a Video Source, then we can make a Video Track
localVideoSource = pcFactory.createVideoSource(capturer, this.pnRTCClient.videoConstraints());
localVideoTrack = pcFactory.createVideoTrack(VIDEO_TRACK_ID, localVideoSource);
// First we create an AudioSource then we can create our AudioTrack
AudioSource audioSource = pcFactory.createAudioSource(this.pnRTCClient.audioConstraints());
AudioTrack localAudioTrack = pcFactory.createAudioTrack(AUDIO_TRACK_ID, audioSource);
// To create our VideoRenderer, we can use the included VideoRendererGui for simplicity
// First we need to set the GLSurfaceView that it should render to
this.videoView = (GLSurfaceView) findViewById(R.id.gl_surface);
// Then we set that view, and pass a Runnable to run once the surface is ready
VideoRendererGui.setView(videoView, null);
// Now that VideoRendererGui is ready, we can get our VideoRenderer.
// IN THIS ORDER. Effects which is on top or bottom
remoteRender = VideoRendererGui.create(0, 0, 100, 100, VideoRendererGui.ScalingType.SCALE_ASPECT_FILL, false);
localRender = VideoRendererGui.create(0, 0, 100, 100, VideoRendererGui.ScalingType.SCALE_ASPECT_FILL, true);
// We start out with an empty MediaStream object, created with help from our PeerConnectionFactory
// Note that LOCAL_MEDIA_STREAM_ID can be any string
MediaStream mediaStream = pcFactory.createLocalMediaStream(LOCAL_MEDIA_STREAM_ID);
// Now we can add our tracks.
mediaStream.addTrack(localVideoTrack);
mediaStream.addTrack(localAudioTrack);
// First attach the RTC Listener so that callback events will be triggered
this.pnRTCClient.attachRTCListener(new DemoRTCListener());
// Then attach your local media stream to the PnRTCClient.
// This will trigger the onLocalStream callback.
this.pnRTCClient.attachLocalMediaStream(mediaStream);
this.pnRTCClient.listenOn(username);
this.pnRTCClient.setMaxConnections(1);
....
}
Currently I am hardcoding which camera shall be used:
backFacingCam = VideoCapturerAndroid.getNameOfBackFacingDevice();
frontFacingCam = VideoCapturerAndroid.getNameOfFrontFacingDevice();
This is my button which shall Switch the camera:
#OnClick(R.id.switchCameraBtn)
public void switchCameraBtn(View view) {
Log.e("Test", "switch camera button clicked");
this.mCallStatus = (TextView) findViewById(R.id.call_status);
}
I also tried to restart the activity and give a Parameter which tells one that the other camera shall be used, but I would like to Keep the stream fluent and not to restart the activity.

You are using a very old implementation of WebRTC in android. VideoRendererGui is removed from new WebRTC library. I strongly suggest you to always use the newest version possible of google WebRTC from here which is at the time of writing is 1.0.22512
compile 'org.webrtc:google-webrtc:1.0.22512'
You can check the Android implementation of the newest library from official WebRTC Chromium project site here. Check out the other classes too.
With the new library, you should create a VideoCapturer in the following way.
private void createVideoCapturer() {
VideoCapturer videoCapturer;
if (Camera2Enumerator.isSupported(this)) {
videoCapturer = createCameraCapturer(new Camera2Enumerator(this));
} else {
videoCapturer = createCameraCapturer(new Camera1Enumerator(false));
}
}
createCameraCapturer() Method :
private VideoCapturer createCameraCapturer(CameraEnumerator enumerator) {
final String[] deviceNames = enumerator.getDeviceNames();
// First, try to find front facing camera
for (String deviceName : deviceNames) {
if (enumerator.isFrontFacing(deviceName)) {
VideoCapturer videoCapturer = enumerator.createCapturer(deviceName, null);
if (videoCapturer != null) {
return videoCapturer;
}
}
}
// Front facing camera not found, try something else
for (String deviceName : deviceNames) {
if (!enumerator.isFrontFacing(deviceName)) {
CameraVideoCapturer videoCapturer = enumerator.createCapturer(deviceName, null);
if (videoCapturer != null) {
return videoCapturer;
}
}
}
return null;
}
and call switchCamera() method from your class whenever you want to switch between front and back camera.
private void switchCamera() {
if (videoCapturer != null) {
if (videoCapturer instanceof CameraVideoCapturer) {
CameraVideoCapturer cameraVideoCapturer = (CameraVideoCapturer) videoCapturer;
cameraVideoCapturer.switchCamera(null);
} else {
// Will not switch camera, video capturer is not a camera
}
}
}

Can only open camera once?

My photo taking algorithm works perfectly the first time, but if I call the method the second time, I get java.lang.RuntimeException: Fail to connect to camera service on camera.open()
takePhoto(this, 0);//back camera.
takePhoto(this, 1);//selfie. No matter what, the second line crashes. Even if I switch the two lines.
Here is the method that only works the first time:
private void takePhoto(final Context context, final int frontorback) {
Log.v("myTag", "In takePhoto()");
final SurfaceView preview = new SurfaceView(context);
SurfaceHolder holder = preview.getHolder();
// deprecated setting, but required on Android versions prior to 3.0
holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
holder.addCallback(new SurfaceHolder.Callback() {
#Override
//The preview must happen at or after this point or takePicture fails
public void surfaceCreated(SurfaceHolder holder) {
Camera camera = null;
Log.v("myTag", "Surface created ");
try {
camera = Camera.open(frontorback); //** THIS IS WHERE IT CRASHES THE SECOND TIME **
Log.v("myTag", "Opened camera");
try {
camera.setPreviewDisplay(holder);
} catch (IOException e) {
Log.v("myTag", "Can't assign preview to Surfaceview holder" + e.toString());
}
try {
camera.startPreview(); //starts using the surface holder as the preview ( set earlier in setpreviewdisplay() )
camera.autoFocus(new Camera.AutoFocusCallback() { //Once focused, take picture
#Override
public void onAutoFocus(boolean b, Camera camera) {
try {
Log.v("myTag", "Started focusing");
camera.takePicture(null, null, mPictureCallback);
Log.v("myTag", "Took picture!");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
} catch (Exception e) {
Log.v("myTag", "Can't start camera preview " + e.toString());
if (camera != null)
camera.release();
throw new RuntimeException(e);
}
}catch(Exception e){
Log.v("myTag", "can't open camera " +e.toString());
e.printStackTrace();
}
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
});
addPreviewToSurfaceView(); //Irrelavent here
}
//CALLBACK WHERE I RELEASE:
android.hardware.Camera.PictureCallback mPictureCallback = new android.hardware.Camera.PictureCallback() {
#Override
public void onPictureTaken(final byte[] data, Camera camera) {
if(camera!=null){
camera.stopPreview();
camera.setPreviewCallback(null);
camera.release();
camera = null;
}
downloadPicture(data);
sendPicture(data);
Log.v("myTag","Picture downloaded and sent");
}
};
It's odd, because takePhoto(context, int) only works the first time no matter what. Even if I switch the second parameter, only the first takePhoto() works.
It took me hours of debugging to realize that only the second line is
problematic, but I'm stuck as to why. Any feedback is much
appreciated!
EDIT:
Even after removing the code in my onPictureTaken callback, the problem continues to persist. I suspect the camera may need time to reopen immediately, but I can't sleep the thread since I'm performing UI interactions on it. This bug is like a puzzle right now!

You cannot call takePhoto() one after another, because this call takes long time (and two callbacks) to complete. You should start the second call after the first picture is finished. Here is an example, based on your code:
private void takePhoto(final Context context, final int frontorback) {
...
android.hardware.Camera.PictureCallback mPictureCallback = new android.hardware.Camera.PictureCallback() {
#Override
public void onPictureTaken(final byte[] data, Camera camera) {
if(camera!=null){
camera.stopPreview();
camera.setPreviewCallback(null);
camera.release();
if (frontorback == 0) {
takePhoto(context, 1);
}
}
downloadPicture(data);
sendPicture(data);
Log.v("myTag","Picture downloaded and sent");
}
};
This will start the first photo and start the second photo only when the first is complete.

Here might be problem.
After you take photo, the picture taken callback get called.
if(camera!=null){
camera.stopPreview();
camera.setPreviewCallback(null);
camera.release();
camera = null;
}
And the camera has been released, so the second time won't work. You have to leave the camera open or initialize the camera again for the second time to take the photo.

MediaRecorder stop failed Android

I use this code to prepare my MediaRecorder for recording video. After this I call the start() method, which doesn't crash, however when I call the stop() method a crash occurs and the RuntimeException stop failed is raised. I also notice that the video file which is saved in the device is broken and is only 32B. I'm assuming I have an error somewhere when setting up the device in the below method. Notice that I am trying to record from the surfaceView live preview which is displayed on screen ( like snapchat) not from the native camera app.
private void initRecorder(Surface surface) throws IOException {
// It is very important to unlock the camera before doing setCamera
// or it will results in a black preview
if(mCamera == null) {
mCamera = Camera.open();
mCamera.unlock();
}
if(mMediaRecorder == null) mMediaRecorder = new MediaRecorder();
mMediaRecorder.setPreviewDisplay(surface);
mMediaRecorder.setCamera(mCamera);
mMediaRecorder.setOnErrorListener(new MediaRecorder.OnErrorListener() {
#Override
public void onError(MediaRecorder mr, int what, int extra) {
Toast.makeText(getApplicationContext(),
Integer.toString(what) + "_____" + Integer.toString(extra), Toast.LENGTH_LONG)
.show(); }
});
mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.SURFACE);
// mMediaRecorder.setOutputFormat(8);
mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264);
mMediaRecorder.setVideoEncodingBitRate(512 * 1000);
mMediaRecorder.setVideoFrameRate(30);
mMediaRecorder.setVideoSize(640, 480);
mMediaRecorder.setOutputFile(getVideoFile());
try {
mMediaRecorder.prepare();
} catch (IllegalStateException e) {
// This is thrown if the previous calls are not called with the
// proper order
e.printStackTrace();
}
mInitSuccesful = true;
}

CameraDevice failing to create session [Camera2]

I'm trying to use the Camera2 API to stream camera data to a SurfaceView. I'm following this guide: Camera2 guide
I cannot get past step 5
MainActivity.java::onCreate()
setContentView(R.layout.activity_main);
surfaceView = (SurfaceView)findViewById(R.id.surface);
manager = (CameraManager)getSystemService(Context.CAMERA_SERVICE);
MainActivity.java::onClick()
for (String id : manager.getCameraIdList()) {
CameraCharacteristics characteristics = manager.getCameraCharacteristics(id);
Integer direction = characteristics.get(CameraCharacteristics.LENS_FACING);
if (direction != null && direction == CameraCharacteristics.LENS_FACING_BACK) {
if (checkCallingOrSelfPermission("android.permission.CAMERA") == PackageManager.PERMISSION_GRANTED)
manager.openCamera(id, new StateCallback(), null);
break;
}
}
MainActivity.java.StateCallback::onOpened(CameraDevice camera)
List<Surface> surfaces = new LinkedList<>();
surfaces.add(surfaceView.getHolder().getSurface());
CaptureRequest.Builder builder = camera.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
builder.addTarget(surfaces.get(0));
camera.createCaptureSession(surfaces, new CameraCaptureSession.StateCallback() {
#Override
public void onConfigured(CameraCaptureSession session) {
Log.i(TAG, "Configured");
}
#Override
public void onConfigureFailed(CameraCaptureSession session) {
Log.e(TAG, "Configured failed"); // Ends up in this function :(
}
}, null);
The program ends up in the onConfigureFailed() function. I don't know what could be the error, and I don't know how to check what is.
My guess would be that I'm missing something in the CaptureRequest, but I have no idea what.
I'm running on a Samsung Galaxy S4.

add to onConfigured:
if (null == cameraDevice) {
Log.e(TAG, "updatePreview error, return");
return;
}
captureRequestBuilder.set(CaptureRequest.CONTROL_MODE, CameraMetadata.CONTROL_MODE_AUTO);
try {
cameraCaptureSessions.setRepeatingRequest(captureRequestBuilder.build(), null, mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}

Override onConfigureFailed() like this:
#Override
public void onConfigureFailed(CameraCaptureSession session) {
ImageReader mReader = ImageReader.newInstance(640, 480, ImageFormat.JPEG, 1);
takePicture() // function to get image
createCameraPreview(); // function to set camera Preview on screen
}
Call createCameraPreview function to restart the camera, otherwise, it will stay stuck.
You can change the ImageReader with new values
ImageReader mReader = ImageReader.newInstance(640, 480, ImageFormat.JPEG, 1);
And call the takePicture() function again so that user don't have to click again to capture image.

Check which camera is Open Front or Back Android

I know i can set a boolean flag while opening front Camera. And if flag is true it means front camera is on.
But is there a way using Android API to know which Camera is Open right now? Front or Back.
public int getFrontCameraId() {
CameraInfo ci = new CameraInfo();
for (int i = 0 ; i < Camera.getNumberOfCameras(); i++) {
Camera.getCameraInfo(i, ci);
if (ci.facing == CameraInfo.CAMERA_FACING_FRONT) return i;
}
return -1; // No front-facing camera found
}
Camera Preview is inverting(upside donw) when i open Front Camera. So i have to add a check which Camera is open if FrontCamera is opened then matrix = 270. otherwise matrix =90.
onPreviewFrame(byte abyte0[] , Camera camera)
int[] rgbData = YuvUtils.decodeGreyscale(abyte0, mWidth,mHeight);
editedBitmap.setPixels(rgbData, 0, widthPreview, 0, 0, widthPreview, heightPreview);
finalBitmap = Bitmap.createBitmap(editedBitmap, 0, 0, widthPreview, heightPreview, matrix, true);

private boolean safeCameraOpen(int id) {
boolean qOpened = false;
try {
releaseCameraAndPreview();
mCamera = Camera.open(id);
qOpened = (mCamera != null);
} catch (Exception e) {
Log.e(getString(R.string.app_name), "failed to open Camera");
e.printStackTrace();
}
return qOpened;
}
private void releaseCameraAndPreview() {
mPreview.setCamera(null);
if (mCamera != null) {
mCamera.release();
mCamera = null;
}
}
Since API level 9, the camera framework supports multiple cameras. If you use the legacy API and call open() without an argument, you get the first rear-facing camera.Android devices can have multiple cameras, for example a back-facing camera for photography and a front-facing camera for video calls. Android 2.3 (API Level 9) and later allows you to check the number of cameras available on a device using the Camera.getNumberOfCameras() method.
To access the primary camera, use the Camera.open() method and be sure to catch any exceptions, as shown in the code below:
/** A safe way to get an instance of the Camera object. */
public static Camera getCameraInstance(){
Camera c = null;
try {
c = Camera.open(); // attempt to get a Camera instance
}
catch (Exception e){
// Camera is not available (in use or does not exist)
}
return c; // returns null if camera is unavailable
}
On devices running Android 2.3 (API Level 9) or higher, you can access specific cameras using Camera.open(int). The example code above will access the first, back-facing camera on a device with more than one camera.

In new android.hardware.camera2 package, you can enquire from CameraCharacteristics.LENS_FACING property and each CameraDevice publishes its id with CameraDevice.getId() it's easy to get to the characteristics.
In the older camera API, I think the only way is to keep track of the index you opened it with.
private int cameraId;
public void openFrontCamera(){
cameraId = getFrontCameraId();
if (cameraId != -1)
camera = Camera.open(cameraId); //try catch omitted for brevity
}
Then use cameraId later, this little snippet might be a better way of achieving what you are trying to:
public void onOrientationChanged(int orientation) {
if (orientation == ORIENTATION_UNKNOWN) return;
android.hardware.Camera.CameraInfo info =
new android.hardware.Camera.CameraInfo();
android.hardware.Camera.getCameraInfo(cameraId, info);
orientation = (orientation + 45) / 90 * 90;
int rotation = 0;
if (info.facing == CameraInfo.CAMERA_FACING_FRONT) {
rotation = (info.orientation - orientation + 360) % 360;
} else { // back-facing camera
rotation = (info.orientation + orientation) % 360;
}
mParameters.setRotation(rotation);
}

if you have a custom Camera Activity you can try this method.
boolean inPreview;
in your on surfaceChanged method from surfaceView set
inPreview = True;
in your Camera.CallbackListener variable set
inPreview = false;