Issue:- Camera Preview different from Image Captured using Camera2 Api. And the problem occurs only in landscape mode.
Requirement:- My requirement is to capture an image in landscape mode using camera2 api.Camera Preview should be in full screen.
I have followed the following github sample :- https://github.com/googlesamples/android-Camera2Basic
This sample works fine in portrait mode as well as in landscape mode if Texture View is wrap_content as the aspect ratio is maintained.
But to display the camera preview in full screen, i changed TextureView to match_parent. By doing that the output got changed. Now preview of camera is different from the image captured.
Please check the images attached here.
1.Camera Preview:-Screenshot of camera preview
2.Image Captured:-On Tapping Picture button
Following is my code snippet:-
fragment_camera2_basic.xml
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.example.android.camera2basic.AutoFitTextureView
android:id="@+id/texture"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true" />
<FrameLayout
android:id="@+id/control"
android:layout_width="match_parent"
android:layout_height="112dp"
android:layout_alignParentBottom="true"
android:layout_alignParentStart="true"
android:background="@color/control_background">
<Button
android:id="@+id/picture"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="@string/picture" />
<ImageButton
android:id="@+id/info"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical|right"
android:padding="20dp"
android:src="@drawable/ic_action_info" />
</FrameLayout>
</RelativeLayout>
Following is the code to capture image:-
/**
* Initiate a still image capture.
*/
private void takePicture() {
lockFocus();
}
/**
* Lock the focus as the first step for a still image capture.
*/
private void lockFocus() {
try {
// This is how to tell the camera to lock focus.
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER,
CameraMetadata.CONTROL_AF_TRIGGER_START);
// Tell #mCaptureCallback to wait for the lock.
mState = STATE_WAITING_LOCK;
mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback,
mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
/**
* Run the precapture sequence for capturing a still image. This method should be called when
* we get a response in {@link #mCaptureCallback} from {@link #lockFocus()}.
*/
private void runPrecaptureSequence() {
try {
// This is how to tell the camera to trigger.
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER,
CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER_START);
// Tell #mCaptureCallback to wait for the precapture sequence to be set.
mState = STATE_WAITING_PRECAPTURE;
mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback,
mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
/**
* Capture a still picture. This method should be called when we get a response in
* {@link #mCaptureCallback} from both {@link #lockFocus()}.
*/
private void captureStillPicture() {
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_STILL_CAPTURE);
captureBuilder.addTarget(mImageReader.getSurface());
// Use the same AE and AF modes as the preview.
captureBuilder.set(CaptureRequest.CONTROL_AF_MODE,
CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
setAutoFlash(captureBuilder);
// Orientation
int rotation = activity.getWindowManager().getDefaultDisplay().getRotation();
captureBuilder.set(CaptureRequest.JPEG_ORIENTATION, getOrientation(rotation));
CameraCaptureSession.CaptureCallback CaptureCallback
= new CameraCaptureSession.CaptureCallback() {
@Override
public void onCaptureCompleted(@NonNull CameraCaptureSession session,
@NonNull CaptureRequest request,
@NonNull TotalCaptureResult result) {
showToast("Saved: " + mFile);
Log.d(TAG, mFile.toString());
unlockFocus();
}
};
mCaptureSession.stopRepeating();
mCaptureSession.abortCaptures();
mCaptureSession.capture(captureBuilder.build(), CaptureCallback, null);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
/**
* Retrieves the JPEG orientation from the specified screen rotation.
*
* @param rotation The screen rotation.
* @return The JPEG orientation (one of 0, 90, 270, and 360)
*/
private int getOrientation(int rotation) {
// Sensor orientation is 90 for most devices, or 270 for some devices (eg. Nexus 5X)
// We have to take that into account and rotate JPEG properly.
// For devices with orientation of 90, we simply return our mapping from ORIENTATIONS.
// For devices with orientation of 270, we need to rotate the JPEG 180 degrees.
return (ORIENTATIONS.get(rotation) + mSensorOrientation + 270) % 360;
}
/**
* Unlock the focus. This method should be called when still image capture sequence is
* finished.
*/
private void unlockFocus() {
try {
// Reset the auto-focus trigger
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER,
CameraMetadata.CONTROL_AF_TRIGGER_CANCEL);
setAutoFlash(mPreviewRequestBuilder);
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();
}
}
I tried to set CaptureRequest.SCALER_CROP_REGION in camera preview builder and image reader as well but it did not work as expected.
