Develop Reference

Camera2 MediaRecorder changes Frame Rate on Galaxy S9

I am not able to get a constant framerate with the camera2 API using MediaRecorder on the Galaxy S9 front camera.
Essentially I am using the example Project from https://github.com/googlesamples/android-Camera2Video but stripped it down to find the error. I removed the mTextureView and use only the mediaRecorder surface.
Here are the relevant code snippets:
#Override
protected void setUpMediaRecorder() throws IOException {
final Activity activity = getActivity();
if (null == activity) {
return;
}
// Camcorder Profile QUALITY_HIGH doenst work
mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.SURFACE);
mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
mMediaRecorder.setVideoEncodingBitRate(30000000);
mMediaRecorder.setVideoFrameRate(30);
mMediaRecorder.setVideoSize(2560, 1440);
mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264);
mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AAC);
mMediaRecorder.prepare();
}
#Override
protected void setUpCaptureRequestBuilder(CaptureRequest.Builder builder) {
Range<Integer> range = getRange();
builder.set(CaptureRequest.CONTROL_AE_TARGET_FPS_RANGE, range);
}
// get highest range
private Range<Integer> getRange() {
CameraManager mCameraManager = (CameraManager) getActivity().getSystemService(Context.CAMERA_SERVICE);
CameraCharacteristics chars = null;
try {
chars = mCameraManager.getCameraCharacteristics(mCameraManager.getCameraIdList()[1]);
} catch (CameraAccessException e) {
e.printStackTrace();
}
Range<Integer>[] ranges = chars.get(CameraCharacteristics.CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES);
Range<Integer> result = null;
for (Range<Integer> range : ranges) {
if (result == null) {
result = range;
} else {
int upper = range.getUpper();
int lower = range.getLower();
if (upper >= result.getUpper() && lower >= result.getLower()) {
result = range;
}
}
}
return result;
}
protected void startRecordingVideo() {
if (null == mCameraDevice) {
return;
}
try {
closeCaptureSession();
setUpMediaRecorder();
mPreviewBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_RECORD);
List<Surface> surfaces = new ArrayList<>();
// Set up Surface for the MediaRecorder
Surface recorderSurface = mMediaRecorder.getSurface();
surfaces.add(recorderSurface);
mPreviewBuilder.addTarget(recorderSurface);
// Start a capture session
// Once the session starts, we can update the UI and start recording
mCameraDevice.createCaptureSession(surfaces, new CameraCaptureSession.StateCallback() {
#Override
public void onConfigured(#NonNull CameraCaptureSession cameraCaptureSession) {
mCaptureSession = cameraCaptureSession;
setUpCaptureRequestBuilder(mPreviewBuilder);
if (null == mCameraDevice) {
return;
}
try {
mCaptureSession.setRepeatingRequest(mPreviewBuilder.build(), null, mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
getActivity().runOnUiThread(new Runnable() {
#Override
public void run() {
// UI
mButtonVideo.setText(R.string.stop);
mIsRecordingVideo = true;
// Start recording
mMediaRecorder.start();
}
});
}
#Override
public void onConfigureFailed(#NonNull CameraCaptureSession cameraCaptureSession) {
Activity activity = getActivity();
if (null != activity) {
Toast.makeText(activity, "Failed", Toast.LENGTH_SHORT).show();
}
}
}, mBackgroundHandler);
} catch (CameraAccessException | IOException e) {
e.printStackTrace();
}
}
getRange() returns a Range of [30,30]. So it should record at 30fps. If I move the camera to some darker areas the frame rate suddenly drops. If locking the AE while moving to a light area the framerate is stable, even in dark areas.
So it seems to have something to do with AE but can not figure out what. Any help?

android camera2 api - transfering preview frames via socket to server

I have gone through the android docs as well as the camera2basic repo and have been able to display camera preview frames on a TextureView. I have two buttons: one that can record the video, the other can capture still images and store it in the device's memory. What I wanna achieve is something different, I want to have all the camera frames being sent to the server in a sequence via sockets in real-time. I have broken down task into smaller chuncks and am presently trying to capture all the camera frames as jpeg images.
This is the CameraCaptureSession.CaptureCallback code whereby I am calling savePreviewShot() which actually replicates the original captureStillPicture() function of Camera2basic repo:
private CameraCaptureSession.CaptureCallback mCaptureCallback
= new CameraCaptureSession.CaptureCallback() {
private void process(CaptureResult result) {
switch (mState) {
case STATE_PREVIEW: {
// We have nothing to do when the camera preview is working normally.
savePreviewShot();
break;
}
case STATE_WAITING_LOCK: {
Integer afState = result.get(CaptureResult.CONTROL_AF_STATE);
if (afState == null) {
captureStillPicture();
} else if (CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED == afState ||
CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED == afState) {
// CONTROL_AE_STATE can be null on some devices
Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
if (aeState == null ||
aeState == CaptureResult.CONTROL_AE_STATE_CONVERGED) {
mState = STATE_PICTURE_TAKEN;
captureStillPicture();
} else {
runPrecaptureSequence();
}
}
break;
}
case STATE_WAITING_PRECAPTURE: {
// CONTROL_AE_STATE can be null on some devices
Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
if (aeState == null ||
aeState == CaptureResult.CONTROL_AE_STATE_PRECAPTURE ||
aeState == CaptureRequest.CONTROL_AE_STATE_FLASH_REQUIRED) {
mState = STATE_WAITING_NON_PRECAPTURE;
}
break;
}
case STATE_WAITING_NON_PRECAPTURE: {
// CONTROL_AE_STATE can be null on some devices
Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
if (aeState == null || aeState != CaptureResult.CONTROL_AE_STATE_PRECAPTURE) {
mState = STATE_PICTURE_TAKEN;
captureStillPicture();
}
break;
}
}
}
This is the savePreviewShot() function:
private void savePreviewShot(){
try {
final Activity activity = getActivity();
if (null == activity || null == mCameraDevice) {
return;
}
// This is the CaptureRequest.Builder that we use to take a picture.
final CaptureRequest.Builder captureBuilder =
mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
captureBuilder.addTarget(mImageReader.getSurface());
// Orientation
int rotation = activity.getWindowManager().getDefaultDisplay().getRotation();
captureBuilder.set(CaptureRequest.JPEG_ORIENTATION, ORIENTATIONS.get(rotation));
CameraCaptureSession.CaptureCallback CaptureCallback
= new CameraCaptureSession.CaptureCallback() {
#Override
public void onCaptureCompleted(CameraCaptureSession session, CaptureRequest request,
TotalCaptureResult result) {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd_HH:mm:ss:SSS");
Date resultdate = new Date(System.currentTimeMillis());
String mFileName = sdf.format(resultdate);
mFile = new File(getActivity().getExternalFilesDir(null), "pic "+mFileName+" preview.jpg");
Log.i("Saved file", ""+mFile.toString());
unlockFocus();
}
};
mCaptureSession.stopRepeating();
mCaptureSession.capture(captureBuilder.build(), CaptureCallback, null);
} catch (Exception e) {
e.printStackTrace();
}
};
However, as you might have figured it out already, such a call causes tremendous lag in displaying the preview on the map and moreover, I am not getting the frames saved as well. Hope you have got the aim I have and the problem I am facing. I have already gone through lots of stuffs on SO and Google but none of them did help.

Have the same exact problem and I was wondering if you got a fix. What I did was set an ImageReader;
private ImageReader videoReader;
private final ImageReader.OnImageAvailableListener onVideoFrameAvailableListener
Loaded it when i openned the camera
videoReader = ImageReader.newInstance(videoImageSize.getWidth(), videoImageSize.getHeight(), ImageFormat.JPEG, 2);
videoReader.setOnImageAvailableListener(onVideoFrameAvailableListener, backgroundHandler);
Added the Surface to the captureSession and processed the image in the listener usingframe = reader.acquireLatestImage();
But yeah, lags a lot the preview and don't know what the solution may be.

Android Camera2 focus state stuck

I need to use Camera2 API on my application. (Api21+)
I found the next sample:
https://github.com/googlesamples/android-Camera2Basic
I downloaded it and started on my phone. When I pressed the "Picture" Button, it's call the takePhoto method.
private void takePicture() {
lockFocus();
}
It is a State machine. Sometimes this machine stuck on STATE_WAITING_LOCK.
My device is waiting for Focus, but nothing happens! (Yes, my device is support auto focus)
case STATE_WAITING_LOCK: {
Integer afState = result.get(CaptureResult.CONTROL_AF_STATE);
if (afState == null) {
captureStillPicture();
} else if (CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED == afState ||
CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED == afState) {
// CONTROL_AE_STATE can be null on some devices
Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
if (aeState == null ||
aeState == CaptureResult.CONTROL_AE_STATE_CONVERGED) {
mState = STATE_PICTURE_TAKEN;
captureStillPicture();
} else {
runPrecaptureSequence();
}
}
break;
}
What is the good solution for this problem?
And this program sometimes crashed here:
private void unlockFocus() {
try {
// Reset the auto-focus trigger
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER,
CameraMetadata.CONTROL_AF_TRIGGER_CANCEL);
setAutoFlash(mPreviewRequestBuilder);
/*HERE*/ mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback,
mBackgroundHandler);
// After this, the camera will go back to the normal state of preview.
mState = STATE_PREVIEW;
mCaptureSession.setRepeatingRequest(mPreviewRequest, mCaptureCallback,
mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
Why can't focus my device?

It seems that your program stucks sometimes in CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED where according to documentation "The AF algorithm has been unable to focus. The lens is not moving." link
Try to cancel the AF_TRIGGER and start it again. Something like this:
if (afState == CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED) {
getRidOfNotFocusedLock();
}
And:
private void getRidOfNotFocusedLock(){
try {
mPreviewRequestBuilder.set(
CaptureRequest.CONTROL_AF_TRIGGER, CaptureRequest.CONTROL_AF_TRIGGER_CANCEL);
mCaptureSession.capture(
captureRequestBuilder.build(), captureSessionCaptureCallback, backgroundHandler);
mPreviewRequestBuilder.set(
CaptureRequest.CONTROL_AF_TRIGGER, CaptureRequest.CONTROL_AF_TRIGGER_START);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}

When I found Lautern's answer, I had to adjust it a little, as it wasn't working for me.
As the program stucks sometimes in CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED, you can try to restart the AF_TRIGGER:
if (afState == CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED) {
restartFocus();
}
private void restartFocus(){
try {
mPreviewRequestBuilder.set(
CaptureRequest.CONTROL_AF_TRIGGER,
CaptureRequest.CONTROL_AF_TRIGGER_CANCEL);
mCaptureSession.capture(
captureRequestBuilder.build(),
captureSessionCaptureCallback,
mBackgroundHandler);
lockFocus();
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
private void lockFocus() {
try {
mPreviewRequestBuilder.set(
CaptureRequest.CONTROL_AF_TRIGGER,
CaptureRequest.CONTROL_AF_TRIGGER_START);
mState = STATE_WAIT_LOCK;
mCaptureSession.capture(
mPreviewRequestBuilder.build(),
mPreviewCaptureCallback,
mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
As some time has passed, since I implemented this, I'm not entirely sure why I had to restart the capture session. But without it, it doesn't work for me.

Session has been closed; further changes are illegal

i was reading about many reports about this, but still couldn't find the answer for me.
Sometimes, after capturing with camera2, an exception is throwing: java.lang.IllegalStateException: Session has been closed; further changes are illegal.
I tried to check all the sessions not being null, when was doing something, but still get this.
Any suggestion ? anything else should i handle?=, which i didn't ?
private CameraCaptureSession.CaptureCallback mCaptureCallback
= new CameraCaptureSession.CaptureCallback() {
private void process(CaptureResult result) {
switch (mState) {
case STATE_PREVIEW: {
if(touchFocusEnabled) {
letSetCaptureSessionOnce = true;
mState = STATE_WAITING_LOCK;
try {
// Reset the auto-focus trigger
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER,
CameraMetadata.CONTROL_AF_TRIGGER_CANCEL);
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER,
CameraMetadata.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback,
mHandler);
} catch (CameraAccessException e) {
L.e("CameraLolipop --- CameraCaptureSession.CaptureCallback " + e);
}
} else {
if(letSetCaptureSessionOnce) {
try {
if ((null != mCaptureSession) && (isCameraOpen)) {
mState = STATE_PREVIEW;
mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback,
mHandler);
letSetCaptureSessionOnce = true;
}
} catch (CameraAccessException e) {
L.e("CameraLolipop --- CameraCaptureSession.CaptureCallback " + e);
}
}
}
break;
}
case STATE_WAITING_LOCK: {
if(touchFocusEnabled) {
mState = STATE_PICTURE_TAKEN;
touchFocusEnabled = false;
try {
if((mCaptureSession != null) && (isCameraOpen)){
mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback,
mHandler);
}
} catch (CameraAccessException e) {
L.e("CameraLolipop --- STATE_WAITING_LOCK " + e);
}
return;
}
Integer afState = result.get(CaptureResult.CONTROL_AF_STATE);
L.d("Focus state ", "STATE_WAITING_LOCK");
boolean fixedFocus = isFixedFocus();
if (afState == null) {
// if ((burstMode) && (getSupportedHardwareLevel() == CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_FULL)) {
// captureStillPictureBurst();
// } else {
captureStillPicture();
// }
} else if ((CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED == afState ||
CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED == afState) || fixedFocus) {
L.d("Focus state ", "CONTROL_AF_STATE_FOCUSED_LOCKED or CONTROL_AF_STATE_NOT_FOCUSED_LOCKED");
// CONTROL_AE_STATE can be null on some devices
Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
if (aeState == null ||
aeState == CaptureResult.CONTROL_AE_STATE_CONVERGED) {
mState = STATE_PICTURE_TAKEN;
if ((burstMode) && (getSupportedHardwareLevel() == CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_FULL)) {
// captureStillPictureBurst();
captureStillPicture();
} else {
captureStillPicture();
}
} else {
runPrecaptureSequence();
}
}
break;
}
case STATE_WAITING_PRECAPTURE: {
L.d("Focus state ", "STATE_WAITING_PRECAPTURE");
// CONTROL_AE_STATE can be null on some devices
Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
if (aeState == null ||
aeState == CaptureResult.CONTROL_AE_STATE_PRECAPTURE ||
aeState == CaptureRequest.CONTROL_AE_STATE_FLASH_REQUIRED || isFixedFocus()) {
mState = STATE_WAITING_NON_PRECAPTURE;
}
break;
}
case STATE_WAITING_NON_PRECAPTURE: {
L.d("Focus state ", "STATE_WAITING_NON_PRECAPTURE");
// CONTROL_AE_STATE can be null on some devices
Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
if (aeState == null || aeState != CaptureResult.CONTROL_AE_STATE_PRECAPTURE) {
mState = STATE_PICTURE_TAKEN;
if ((burstMode) && (getSupportedHardwareLevel() == CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_FULL)) {
// captureStillPictureBurst();
captureStillPicture();
} else {
captureStillPicture();
}
}
break;
}
case STATE_PICTURE_TAKEN: {
Integer afState = result.get(CaptureResult.CONTROL_AF_STATE);
L.d("TOUCH", " afState " + afState);
mState = STATE_PREVIEW;
if(afState == 4) {
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE,
CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
}
if(afState == 0) {
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
#Override
public void run() {
mPreviewRequestBuilder
.set(CaptureRequest.CONTROL_AF_REGIONS, null);
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE,
CameraMetadata.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
}
}, 2500);
}
break;
}
}
}
#Override
public void onCaptureProgressed(CameraCaptureSession session,
CaptureRequest request,
CaptureResult partialResult) {
super.onCaptureProgressed(session, request, partialResult);
// process(partialResult);
}
#Override
public void onCaptureCompleted(CameraCaptureSession session,
CaptureRequest request,
TotalCaptureResult result) {
// if ((mState != STATE_PREVIEW) || (touchFocusEnabled)) {
super.onCaptureCompleted(session, request, result);
if(session != null) {
process(result);
}
}
};
and here is where session is being created:
private CameraCaptureSession.StateCallback mSessionPreviewStateCallback = new CameraCaptureSession.StateCallback() {
#Override
public void onConfigured(CameraCaptureSession cameraCaptureSession) {
L.i("Thread", "onConfigured---->" + Thread.currentThread().getName());
// The camera is already closed
if(null == mCameraDevice) {
return;
}
try {
mCaptureSession = cameraCaptureSession;
mCameraSessionIsClosed = false;
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE,
CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
if((isCameraOpen) && (mCaptureSession != null)){
mPreviewRequest = mPreviewRequestBuilder.build();
mCaptureSession.setRepeatingRequest(mPreviewRequest, mCaptureCallback, mHandler);
}
L.d("ex0003", "Test... mSessionPreviewStateCallback ");
} catch (CameraAccessException e) {
L.e("CameraLolipop --- openCamera() " + e);
}
}
#Override
public void onConfigureFailed(CameraCaptureSession cameraCaptureSession) {
Toast.makeText(getActivity(), "onConfigureFailed---Preview", Toast.LENGTH_SHORT).show();
}
};
and in onPause closeCamera() is being called:
try {
if(mCameraDevice == null && mCameraIsClosed) {
return;
}
if((mCaptureSession != null) && (isCameraOpen)) {
try {
mCaptureSession.abortCaptures();
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
mCameraOpenCloseLock.acquire();
if (null != mCaptureSession) {
mCaptureSession.close();
mCaptureSession = null;
mCameraSessionIsClosed = true;
}
if (null != mCameraDevice) {
mCameraDevice.close();
mCameraDevice = null;
isCameraOpen = false;
mCameraIsClosed = true;
}
if (null != mImageReader) {
mImageReader.close();
mImageReader = null;
}
} catch (InterruptedException e) {
throw new RuntimeException("Interrupted while trying to lock camera closing.", e);
} finally {
mCameraOpenCloseLock.release();
}
and after stopBackgroundThread() and super.onPause() are being called.

In my case problem was createCaptureRequest being called multiple when another is already in process(onConfigured/onConfigureFailed called). What I end up was creating a boolean variable that keeps track if camera_preview is already in process, if so then do not make another createCaptureRequest.

Check if all the camera configurations have been set with a flag, as #Rohit suggested or give some delay to the repeatingRequest of your mCaptureSession while it setting the configuration for you in parallel in the background. In my case I solved this exception by giving a delay of 500 mS to set the repeatingRequest like this:
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
try {
mCaptureSession.setRepeatingRequest(mPreviewRequestBuilder.build(),
mCaptureCallback, null);
} catch (CameraAccessException e) {
Log.e(TAG, "Failed to start camera preview because it couldn't access camera", e);
} catch (IllegalStateException e) {
Log.e(TAG, "Failed to start camera preview.", e);
}
}
}, 500);
Also, the same problem occurs when you first time grant permissions and initially start your camera preview(app crashes), but there you will get CameraAccessException stating "Failed to start camera session". In that case, you should give the same amount of delay while creating capture sessions like below:
void startCaptureSession() {
if (!isCameraOpened() || !mPreview.isReady() || mImageReader == null) {
return;
}
previewSize = chooseOptimalSize();
mPreview.setBufferSize(previewSize.getWidth(), previewSize.getHeight());
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
try {
Surface surface = mPreview.getSurface();
mPreviewRequestBuilder = mCamera.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
mPreviewRequestBuilder.addTarget(surface);
mCamera.createCaptureSession(Arrays.asList(surface, mImageReader.getSurface()),
mSessionCallback, mBackgroundHandler);
} catch (CameraAccessException e) {
throw new RuntimeException("Failed to start camera session");
}
}
}, 500);
}
I hope it helps.

In the documentation it says:
if this session is no longer active, either because the session was explicitly closed, a new session has been created or the camera device has been closed.
If you are using the camera2api sample-project, this means: You either call openCamera(), createCameraPreviewSession() or closeCamera() while another createCameraPreviewSession() was called aswell.
I solved this with a global variable, that is always set to true, when the function createCameraPreviewSession() is called; and is set to false, 10MS after createCameraPreviewSession() was finished. If this variable is true, I block all new createCameraPreviewSession() calls and also all closeCamera() calls.
This solution worked for me. However, I don't know if there is a fundamental reason, why you should not use this. If somebody knows better, please let me know.

I'm not sure if this will work, but try it and let me know if it worked.
private CameraCaptureSession.StateCallback mSessionPreviewStateCallback = new CameraCaptureSession.StateCallback() {
#Override
public void onConfigured(CameraCaptureSession cameraCaptureSession) {
L.i("Thread", "onConfigured---->" + Thread.currentThread().getName());
// The camera is already closed
if(null == mCameraDevice) {
return;
}
try {
mCaptureSession = cameraCaptureSession;
mCameraSessionIsClosed = false;
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE,
CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
if((isCameraOpen) && (mCaptureSession != null)){
mPreviewRequest = mPreviewRequestBuilder.build();
mCaptureSession.setRepeatingRequest(mPreviewRequest, mCaptureCallback, mHandler);
}
L.d("ex0003", "Test... mSessionPreviewStateCallback ");
} catch (CameraAccessException e) {
Log.e(TAG, "Failed to start camera preview because it couldn't access camera", e);
} catch (IllegalStateException e) {
Log.e(TAG, "Failed to start camera preview.", e);
}
}
#Override
public void onConfigureFailed(CameraCaptureSession cameraCaptureSession) {
Toast.makeText(getActivity(), "onConfigureFailed---Preview", Toast.LENGTH_SHORT).show();
}
#Override
public void onClosed(#NonNull CameraCaptureSession session) {
if (mCaptureSession != null && mCaptureSession.equals(session)) {
mCaptureSession = null;
}
}
};

This error occurs if the camera is opened before setting all the configuration to the preview request builder. Hence you must first set all the parameters like the TextureView size, camera output size etc.
Here is code from google's sample app:
setUpCameraOutputs(width, height);
configureTransform(width, height);
Activity activity = getActivity();
CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE);
manager.openCamera(mCameraId, mStateCallback, mBackgroundHandler);

Enable a preview during a capture session on Camera2

I'm building a camera app based on Camera2, but the picture I save is not matching the latest one I saw on my surface view. It seems that the Preview session works but when I ask for a capture, the new request stop the preview and capture the image. The surface view freeze on the latest pic and that create a gap between the time I press the shutter button (preview running and request capture) and the onCaptureCompleted from the capture request.
Here is the preview session
private void createCameraPreviewSession() {
try {
SurfaceTexture texture = mTextureView.getSurfaceTexture();
assert texture != null;
texture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight());
Log.d(TAG, "here is the width of texture" + mPreviewSize.getWidth());
Log.d(TAG, "here is the height of texture" +mPreviewSize.getHeight());
Surface surface = new Surface(texture);
mPreviewRequestBuilder
= mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
mPreviewRequestBuilder.addTarget(surface);
mCameraDevice.createCaptureSession(Arrays.asList(surface, mImageReader.getSurface()),
new CameraCaptureSession.StateCallback() {
#Override
public void onConfigured(#NonNull CameraCaptureSession cameraCaptureSession) {
if (null == mCameraDevice) {
return;
}
mCaptureSession = cameraCaptureSession;
try {
mPreviewRequest = mPreviewRequestBuilder.build();
mCaptureSession.setRepeatingRequest(mPreviewRequest,
mCaptureCallback, mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
#Override
public void onConfigureFailed(
#NonNull CameraCaptureSession cameraCaptureSession) {
showToast("Failed");
}
}, null
);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
the mCaptureCallback is defined as below :
private CameraCaptureSession.CaptureCallback mCaptureCallback
= new CameraCaptureSession.CaptureCallback() {
private void process(CaptureResult result) {
switch (mState) {
case STATE_PREVIEW:
break;
case STATE_CAPTURE:
mState = STATE_PREVIEW;
capturePicture();
break;
}
}
#Override
public void onCaptureProgressed(#NonNull CameraCaptureSession session,
#NonNull CaptureRequest request,
#NonNull CaptureResult partialResult) {
process(partialResult);
}
#Override
public void onCaptureCompleted(#NonNull CameraCaptureSession session,
#NonNull CaptureRequest request,
#NonNull TotalCaptureResult result) {
TotalCaptureResult iResult = result;
Log.d(TAG, "Frame on Completed: "+result.getFrameNumber());
process(result);
}
}
What's happening is that I repeating the preview and it works. the process is just used to keep it running and nothing happened until the mState is set to CAPTURE.
It's set to capture when we click on the shutter button. When I click on the button, I call:
private void takePicture(){
try {
mFile = ImageSaver.generateNewFileImage();
mState = STATE_CAPTURE;
mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback,
mBackgroundHandler);
} catch (CameraAccessException e) {
Log.e(TAG,"Camera exception",e);
}
}
I call then CapturePicture as mState is in Capture as defined in the mCaptureCallback
private void capturePicture() {
mTakePictureRunnable = new Runnable() {
#Override
public void run() {
takePictureNow();
}
};
mBackgroundHandler.post(mTakePictureRunnable);
}
the takePicutreNow is defined
private void takePictureNow() {
Log.d(TAG, "Running captureStillPicture");
try {
if (null == mCameraDevice) {
return;
}
// This is the CaptureRequest.Builder that we use to take a picture.
final CaptureRequest.Builder captureBuilder =
mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);
captureBuilder.addTarget(mImageReader.getSurface());
SurfaceTexture texture = mTextureView.getSurfaceTexture();
assert texture != null;
texture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight());
Log.d(TAG, "here is the width of texture" + mPreviewSize.getWidth());
Log.d(TAG, "here is the height of texture" + mPreviewSize.getHeight());
Surface surface = new Surface(texture);
captureBuilder.addTarget(surface);
// Orientation
int rotation = getWindowManager().getDefaultDisplay().getRotation();
captureBuilder.set(CaptureRequest.JPEG_ORIENTATION, ORIENTATIONS.get(rotation));
//Location if needed
boolean Location_Saved = CameraSettings.Instance().getBoolean(CameraSettings.SAVE_LOCATION,
getResources().getBoolean(R.bool.action_camera_settings_dflt_location));
if(Location_Saved == true) {
captureBuilder.set(CaptureRequest.JPEG_GPS_LOCATION, mLocationManager.getCurrentLocation());
} else {
captureBuilder.set(CaptureRequest.JPEG_GPS_LOCATION, null);
}
CameraCaptureSession.CaptureCallback CaptureCallback
= new CameraCaptureSession.CaptureCallback() {
#Override
public void onCaptureStarted(#NonNull CameraCaptureSession session,
#NonNull CaptureRequest request,
#NonNull long timestamp,
#NonNull long framenumber) {
playShutterSound();
showShutterAnimation();
}
#Override
public void onCaptureCompleted(#NonNull CameraCaptureSession session,
#NonNull CaptureRequest request,
#NonNull TotalCaptureResult result) {
Log.d(TAG, mFile.toString());
mState = STATE_PREVIEW;
}
};
mCaptureSession.capture(captureBuilder.build(), CaptureCallback, null);
mCaptureSession.stopRepeating();
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
This process is working but I got a lag between the press and the imagesave and the latest pic I saw on the screen from the preview is not exactly the same saved if I move quickly.
It seems that the capture do not update the surface and the surface only show when we were in Preview
Any idea to see what I save ?
Thanks

The surface will freeze when you take an image, that might not be the image that gets saved. If you still want to show camera preview on the screen, you just have to restart the camera preview by calling the function you used to create preview at the first time.