Camera2CameraControl.java
/*
* Copyright 2019 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.camera.camera2.impl;
import android.graphics.Rect;
import android.hardware.camera2.CameraCaptureSession;
import android.hardware.camera2.CameraCaptureSession.CaptureCallback;
import android.hardware.camera2.CameraCharacteristics;
import android.hardware.camera2.CameraDevice;
import android.hardware.camera2.CaptureRequest;
import android.hardware.camera2.TotalCaptureResult;
import android.util.Rational;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.RestrictTo;
import androidx.annotation.VisibleForTesting;
import androidx.annotation.WorkerThread;
import androidx.camera.camera2.impl.annotation.CameraExecutor;
import androidx.camera.core.CameraControlInternal;
import androidx.camera.core.CaptureConfig;
import androidx.camera.core.Config;
import androidx.camera.core.FlashMode;
import androidx.camera.core.FocusMeteringAction;
import androidx.camera.core.FocusMeteringResult;
import androidx.camera.core.SessionConfig;
import androidx.camera.core.impl.utils.futures.Futures;
import androidx.core.util.Preconditions;
import com.google.common.util.concurrent.ListenableFuture;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.Executor;
import java.util.concurrent.ScheduledExecutorService;
/**
* A Camera2 implementation for CameraControlInternal interface
*
* @hide
*/
@RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
public final class Camera2CameraControl implements CameraControlInternal {
@VisibleForTesting
final CameraControlSessionCallback mSessionCallback;
@SuppressWarnings("WeakerAccess") /* synthetic accessor */
@CameraExecutor
final Executor mExecutor;
private final CameraCharacteristics mCameraCharacteristics;
private final ControlUpdateCallback mControlUpdateCallback;
private final SessionConfig.Builder mSessionConfigBuilder = new SessionConfig.Builder();
@SuppressWarnings("WeakerAccess") /* synthetic accessor */
volatile Rational mPreviewAspectRatio = null;
private final FocusMeteringControl mFocusMeteringControl;
private final ZoomControl mZoomControl;
private final TorchControl mTorchControl;
// use volatile modifier to make these variables in sync in all threads.
private volatile boolean mIsTorchOn = false;
@FlashMode
private volatile int mFlashMode = FlashMode.OFF;
private volatile boolean mIsActive = false;
//******************** Should only be accessed by executor *****************************//
private Rect mCropRect = null;
//**************************************************************************************//
/**
* Constructor for a Camera2CameraControl.
*
* <p>All {@code controlUpdateListener} invocations will be on the provided {@code executor}.
*
* <p>All tasks scheduled by {@code scheduler} will be immediately executed by {@code executor}.
*
* @param cameraCharacteristics Characteristics for the camera being controlled.
* @param scheduler Scheduler used for scheduling tasks in the future.
* @param executor Camera executor for synchronizing and offloading all commands.
* @param controlUpdateCallback Listener which will be notified of control changes.
*/
public Camera2CameraControl(@NonNull CameraCharacteristics cameraCharacteristics,
@NonNull ScheduledExecutorService scheduler,
@NonNull @CameraExecutor Executor executor,
@NonNull ControlUpdateCallback controlUpdateCallback) {
mCameraCharacteristics = cameraCharacteristics;
mControlUpdateCallback = controlUpdateCallback;
mExecutor = executor;
mSessionCallback = new CameraControlSessionCallback(mExecutor);
mSessionConfigBuilder.setTemplateType(getDefaultTemplate());
mSessionConfigBuilder.addRepeatingCameraCaptureCallback(
CaptureCallbackContainer.create(mSessionCallback));
mFocusMeteringControl = new FocusMeteringControl(this, scheduler, mExecutor);
mZoomControl = new ZoomControl(this, mCameraCharacteristics);
mTorchControl = new TorchControl(this);
// Initialize the session config
mExecutor.execute(this::updateSessionConfig);
}
@NonNull
public ZoomControl getZoomControl() {
return mZoomControl;
}
@NonNull
public TorchControl getTorchControl() {
return mTorchControl;
}
/**
* Set current active state. Set active if it is ready to trigger camera control operation.
*
* <p>Most operations during inactive state do nothing. Some states are reset to default
* once it is changed to inactive state.
*/
void setActive(boolean isActive) {
mIsActive = isActive;
mFocusMeteringControl.setActive(isActive);
mZoomControl.setActive(isActive);
}
@WorkerThread
public void setPreviewAspectRatio(@Nullable Rational previewAspectRatio) {
mPreviewAspectRatio = previewAspectRatio;
}
@NonNull
@Override
public ListenableFuture<FocusMeteringResult> startFocusAndMetering(
@NonNull FocusMeteringAction action) {
return mFocusMeteringControl.startFocusAndMetering(action, mPreviewAspectRatio);
}
@NonNull
@Override
public ListenableFuture<Void> cancelFocusAndMetering() {
mExecutor.execute(mFocusMeteringControl::cancelFocusAndMetering);
return Futures.immediateFuture(null);
}
@NonNull
@Override
public ListenableFuture<Void> setZoomRatio(float ratio) {
return mZoomControl.setZoomRatio(ratio);
}
@NonNull
@Override
public ListenableFuture<Void> setLinearZoom(float linearZoom) {
return mZoomControl.setLinearZoom(linearZoom);
}
/** {@inheritDoc} */
@Override
public void setCropRegion(@Nullable final Rect crop) {
mExecutor.execute(() -> setCropRegionInternal(crop));
}
@FlashMode
@Override
public int getFlashMode() {
return mFlashMode;
}
/** {@inheritDoc} */
@Override
public void setFlashMode(@FlashMode int flashMode) {
// update mFlashMode immediately so that following getFlashMode() returns correct value.
mFlashMode = flashMode;
mExecutor.execute(this::updateSessionConfig);
}
/** {@inheritDoc} */
@Override
@NonNull
public ListenableFuture<Void> enableTorch(final boolean torch) {
// update isTorchOn immediately so that following isTorchOn() returns correct value.
mIsTorchOn = torch;
mExecutor.execute(() -> enableTorchInternal(torch));
// TODO(b/143514107): implement #enableTorch which returns ListenableFuture.
return mTorchControl.enableTorch(torch);
}
/** {@inheritDoc} */
@Override
public boolean isTorchOn() {
return mIsTorchOn;
}
/**
* Issues a {@link CaptureRequest#CONTROL_AF_TRIGGER_START} request to start auto focus scan.
*/
@Override
public void triggerAf() {
mExecutor.execute(mFocusMeteringControl::triggerAf);
}
/**
* Issues a {@link CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER_START} request to start auto
* exposure scan.
*/
@Override
public void triggerAePrecapture() {
mExecutor.execute(mFocusMeteringControl::triggerAePrecapture);
}
/**
* Issues {@link CaptureRequest#CONTROL_AF_TRIGGER_CANCEL} or {@link
* CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER_CANCEL} request to cancel auto focus or auto
* exposure scan.
*/
@Override
public void cancelAfAeTrigger(final boolean cancelAfTrigger,
final boolean cancelAePrecaptureTrigger) {
mExecutor.execute(() -> mFocusMeteringControl.cancelAfAeTrigger(cancelAfTrigger,
cancelAePrecaptureTrigger));
}
/** {@inheritDoc} */
@Override
public void submitCaptureRequests(@NonNull final List<CaptureConfig> captureConfigs) {
mExecutor.execute(() -> submitCaptureRequestsInternal(captureConfigs));
}
@WorkerThread
private int getDefaultTemplate() {
return CameraDevice.TEMPLATE_PREVIEW;
}
@WorkerThread
void updateSessionConfig() {
mSessionConfigBuilder.setImplementationOptions(getSessionOptions());
mControlUpdateCallback.onCameraControlUpdateSessionConfig(mSessionConfigBuilder.build());
}
@SuppressWarnings("WeakerAccess") /* synthetic accessor */
@WorkerThread
void setCropRegionInternal(final Rect crop) {
mCropRect = crop;
updateSessionConfig();
}
@WorkerThread
@NonNull
Rect getCropSensorRegion() {
Rect cropRect = mCropRect;
if (cropRect == null) {
cropRect = getSensorRect();
}
return cropRect;
}
@WorkerThread
@NonNull
Rect getSensorRect() {
return Preconditions.checkNotNull(
mCameraCharacteristics.get(CameraCharacteristics.SENSOR_INFO_ACTIVE_ARRAY_SIZE));
}
@WorkerThread
void removeCaptureResultListener(@NonNull CaptureResultListener listener) {
mSessionCallback.removeListener(listener);
}
@WorkerThread
void addCaptureResultListener(@NonNull CaptureResultListener listener) {
mSessionCallback.addListener(listener);
}
@SuppressWarnings("WeakerAccess") /* synthetic accessor */
@WorkerThread
void enableTorchInternal(boolean torch) {
if (!torch) {
// Send capture request with AE_MODE_ON + FLASH_MODE_OFF to turn off torch.
CaptureConfig.Builder singleRequestBuilder = new CaptureConfig.Builder();
singleRequestBuilder.setTemplateType(getDefaultTemplate());
singleRequestBuilder.setUseRepeatingSurface(true);
Camera2ImplConfig.Builder configBuilder = new Camera2ImplConfig.Builder();
configBuilder.setCaptureRequestOption(CaptureRequest.CONTROL_AE_MODE,
getSupportedAeMode(CaptureRequest.CONTROL_AE_MODE_ON));
configBuilder.setCaptureRequestOption(CaptureRequest.FLASH_MODE,
CaptureRequest.FLASH_MODE_OFF);
singleRequestBuilder.addImplementationOptions(configBuilder.build());
submitCaptureRequestsInternal(Collections.singletonList(singleRequestBuilder.build()));
}
updateSessionConfig();
}
@WorkerThread
void submitCaptureRequestsInternal(final List<CaptureConfig> captureConfigs) {
mControlUpdateCallback.onCameraControlCaptureRequests(captureConfigs);
}
/**
* Gets session options by current status.
*
* <p>The session options are based on the current torch status, flash mode, focus area, crop
* area, etc... They should be appended to the repeat request.
*/
@VisibleForTesting
@WorkerThread
Config getSessionOptions() {
Camera2ImplConfig.Builder builder = new Camera2ImplConfig.Builder();
builder.setCaptureRequestOption(
CaptureRequest.CONTROL_MODE, CaptureRequest.CONTROL_MODE_AUTO);
// AF Mode is assigned in mFocusMeteringControl.
mFocusMeteringControl.addFocusMeteringOptions(builder);
int aeMode = CaptureRequest.CONTROL_AE_MODE_ON;
if (mIsTorchOn) {
builder.setCaptureRequestOption(CaptureRequest.FLASH_MODE,
CaptureRequest.FLASH_MODE_TORCH);
} else {
switch (mFlashMode) {
case FlashMode.OFF:
aeMode = CaptureRequest.CONTROL_AE_MODE_ON;
break;
case FlashMode.ON:
aeMode = CaptureRequest.CONTROL_AE_MODE_ON_ALWAYS_FLASH;
break;
case FlashMode.AUTO:
aeMode = CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH;
break;
}
}
builder.setCaptureRequestOption(CaptureRequest.CONTROL_AE_MODE, getSupportedAeMode(aeMode));
builder.setCaptureRequestOption(
CaptureRequest.CONTROL_AWB_MODE,
getSupportedAwbMode(CaptureRequest.CONTROL_AWB_MODE_AUTO));
if (mCropRect != null) {
builder.setCaptureRequestOption(CaptureRequest.SCALER_CROP_REGION, mCropRect);
}
return builder.build();
}
/**
* Returns a supported AF mode which will be preferredMode if it is supported.
*
* <p><pre>If preferredMode is not supported, fallback with the following priority (highest to
* lowest).
* 1) {@link CaptureRequest#CONTROL_AF_MODE_CONTINUOUS_PICTURE}
* 2) {@link CaptureRequest#CONTROL_AF_MODE_AUTO)}
* 3) {@link CaptureRequest#CONTROL_AF_MODE_OFF}
* </pre>
*/
@WorkerThread
int getSupportedAfMode(int preferredMode) {
int[] modes = mCameraCharacteristics.get(CameraCharacteristics.CONTROL_AF_AVAILABLE_MODES);
if (modes == null) {
return CaptureRequest.CONTROL_AF_MODE_OFF;
}
// if preferredMode is supported, use it
if (isModeInList(preferredMode, modes)) {
return preferredMode;
}
// if not found, priority is CONTINUOUS_PICTURE > AUTO > OFF
if (isModeInList(CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE, modes)) {
return CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE;
} else if (isModeInList(CaptureRequest.CONTROL_AF_MODE_AUTO, modes)) {
return CaptureRequest.CONTROL_AF_MODE_AUTO;
}
return CaptureRequest.CONTROL_AF_MODE_OFF;
}
/**
* Returns a supported AE mode which will be preferredMode if it is supported.
*
* <p><pre>If preferredMode is not supported, fallback with the following priority (highest to
* lowest).
* 1) {@link CaptureRequest#CONTROL_AE_MODE_ON}
* 2) {@link CaptureRequest#CONTROL_AE_MODE_OFF)}
* </pre>
*/
@WorkerThread
private int getSupportedAeMode(int preferredMode) {
int[] modes = mCameraCharacteristics.get(CameraCharacteristics.CONTROL_AE_AVAILABLE_MODES);
if (modes == null) {
return CaptureRequest.CONTROL_AE_MODE_OFF;
}
// if preferredMode is supported, use it
if (isModeInList(preferredMode, modes)) {
return preferredMode;
}
// if not found, priority is AE_ON > AE_OFF
if (isModeInList(CaptureRequest.CONTROL_AE_MODE_ON, modes)) {
return CaptureRequest.CONTROL_AE_MODE_ON;
}
return CaptureRequest.CONTROL_AE_MODE_OFF;
}
/**
* Returns a supported AWB mode which will be preferredMode if it is supported.
*
* <p><pre>If preferredMode is not supported, fallback with the following priority (highest to
* lowest).
* 1) {@link CaptureRequest#CONTROL_AWB_MODE_AUTO}
* 2) {@link CaptureRequest#CONTROL_AWB_MODE_OFF)}
* </pre>
*/
@WorkerThread
private int getSupportedAwbMode(int preferredMode) {
int[] modes = mCameraCharacteristics.get(CameraCharacteristics.CONTROL_AWB_AVAILABLE_MODES);
if (modes == null) {
return CaptureRequest.CONTROL_AWB_MODE_OFF;
}
// if preferredMode is supported, use it
if (isModeInList(preferredMode, modes)) {
return preferredMode;
}
// if not found, priority is AWB_AUTO > AWB_OFF
if (isModeInList(CaptureRequest.CONTROL_AWB_MODE_AUTO, modes)) {
return CaptureRequest.CONTROL_AWB_MODE_AUTO;
}
return CaptureRequest.CONTROL_AWB_MODE_OFF;
}
@WorkerThread
private boolean isModeInList(int mode, int[] modeList) {
for (int m : modeList) {
if (mode == m) {
return true;
}
}
return false;
}
/** An interface to listen to camera capture results. */
interface CaptureResultListener {
/**
* Callback to handle camera capture results.
*
* @param captureResult camera capture result.
* @return true to finish listening, false to continue listening.
*/
boolean onCaptureResult(@NonNull TotalCaptureResult captureResult);
}
static final class CameraControlSessionCallback extends CaptureCallback {
/* synthetic accessor */final Set<CaptureResultListener> mResultListeners = new HashSet<>();
@CameraExecutor
private final Executor mExecutor;
CameraControlSessionCallback(@NonNull @CameraExecutor Executor executor) {
mExecutor = executor;
}
@WorkerThread
void addListener(@NonNull CaptureResultListener listener) {
mResultListeners.add(listener);
}
@WorkerThread
void removeListener(@NonNull CaptureResultListener listener) {
mResultListeners.remove(listener);
}
@Override
public void onCaptureCompleted(
@NonNull CameraCaptureSession session,
@NonNull CaptureRequest request,
@NonNull final TotalCaptureResult result) {
mExecutor.execute(() -> {
Set<CaptureResultListener> removeSet = new HashSet<>();
for (CaptureResultListener listener : mResultListeners) {
boolean isFinished = listener.onCaptureResult(result);
if (isFinished) {
removeSet.add(listener);
}
}
if (!removeSet.isEmpty()) {
mResultListeners.removeAll(removeSet);
}
});
}
}
}