Camera2: Add hidden experimental tearDown method
Bug: 18949148
Change-Id: I6264d95a26ebf51cce6114c9a86b9561f7c60ab5
diff --git a/core/java/android/hardware/camera2/CameraCaptureSession.java b/core/java/android/hardware/camera2/CameraCaptureSession.java
index 46cafad..46ffe36 100644
--- a/core/java/android/hardware/camera2/CameraCaptureSession.java
+++ b/core/java/android/hardware/camera2/CameraCaptureSession.java
@@ -138,6 +138,45 @@
*/
public abstract void prepare(@NonNull Surface surface) throws CameraAccessException;
+
+ /**
+ * <p>Free all buffers allocated for an output Surface.</p>
+ *
+ * <p>Normally, once allocated, the image buffers for a given output Surface remain allocated
+ * for the lifetime of the capture session, to minimize latency of captures and to reduce
+ * memory allocation overhead.</p>
+ *
+ * <p>However, in some cases, it may be desirable for allocated buffers to be freed to reduce
+ * the application's memory consumption, if the particular output Surface will not be used by
+ * the application for some time.</p>
+ *
+ * <p>The tearDown() method can be used to perform this operation. After the call finishes, all
+ * unfilled image buffers will have been freed. Any future use of the target Surface may require
+ * allocation of additional buffers, as if the session had just been created. Buffers being
+ * held by the application (either explicitly as Image objects from ImageReader, or implicitly
+ * as the current texture in a SurfaceTexture or the current contents of a RS Allocation, will
+ * remain valid and allocated even when tearDown is invoked.</p>
+ *
+ * <p>A Surface that has had tearDown() called on it is eligible to have prepare() invoked on it
+ * again even if it was used as a request target before the tearDown() call, as long as it
+ * doesn't get used as a target of a request between the tearDown() and prepare() calls.</p>
+ *
+ * @param surface the output Surface for which buffers should be freed. Must be one of the
+ * the output Surfaces used to create this session.
+ *
+ * @throws CameraAccessException if the camera device is no longer connected or has
+ * encountered a fatal error.
+ * @throws IllegalStateException if this session is no longer active, either because the session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.
+ * @throws IllegalArgumentException if the Surface is invalid, not part of this Session, or has
+ * already been used as a target of a CaptureRequest in this
+ * session or immediately prior sessions.
+ *
+ * @hide
+ */
+ public abstract void tearDown(@NonNull Surface surface) throws CameraAccessException;
+
/**
* <p>Submit a request for an image to be captured by the camera device.</p>
*
diff --git a/core/java/android/hardware/camera2/ICameraDeviceUser.aidl b/core/java/android/hardware/camera2/ICameraDeviceUser.aidl
index 1574f93..7cb3673 100644
--- a/core/java/android/hardware/camera2/ICameraDeviceUser.aidl
+++ b/core/java/android/hardware/camera2/ICameraDeviceUser.aidl
@@ -100,4 +100,6 @@
int flush(out LongParcelable lastFrameNumber);
int prepare(int streamId);
+
+ int tearDown(int streamId);
}
diff --git a/core/java/android/hardware/camera2/impl/CameraCaptureSessionImpl.java b/core/java/android/hardware/camera2/impl/CameraCaptureSessionImpl.java
index 3c19cd2..d325c77 100644
--- a/core/java/android/hardware/camera2/impl/CameraCaptureSessionImpl.java
+++ b/core/java/android/hardware/camera2/impl/CameraCaptureSessionImpl.java
@@ -146,6 +146,11 @@
}
@Override
+ public void tearDown(Surface surface) throws CameraAccessException {
+ mDeviceImpl.tearDown(surface);
+ }
+
+ @Override
public synchronized int capture(CaptureRequest request, CaptureCallback callback,
Handler handler) throws CameraAccessException {
if (request == null) {
diff --git a/core/java/android/hardware/camera2/impl/CameraConstrainedHighSpeedCaptureSessionImpl.java b/core/java/android/hardware/camera2/impl/CameraConstrainedHighSpeedCaptureSessionImpl.java
index d732535..a920e2b 100644
--- a/core/java/android/hardware/camera2/impl/CameraConstrainedHighSpeedCaptureSessionImpl.java
+++ b/core/java/android/hardware/camera2/impl/CameraConstrainedHighSpeedCaptureSessionImpl.java
@@ -169,6 +169,11 @@
}
@Override
+ public void tearDown(Surface surface) throws CameraAccessException {
+ mSessionImpl.tearDown(surface);
+ }
+
+ @Override
public int capture(CaptureRequest request, CaptureCallback listener, Handler handler)
throws CameraAccessException {
throw new UnsupportedOperationException("Constrained high speed session doesn't support"
diff --git a/core/java/android/hardware/camera2/impl/CameraDeviceImpl.java b/core/java/android/hardware/camera2/impl/CameraDeviceImpl.java
index c594228..91d623e 100644
--- a/core/java/android/hardware/camera2/impl/CameraDeviceImpl.java
+++ b/core/java/android/hardware/camera2/impl/CameraDeviceImpl.java
@@ -679,6 +679,31 @@
}
}
+ public void tearDown(Surface surface) throws CameraAccessException {
+ if (surface == null) throw new IllegalArgumentException("Surface is null");
+
+ synchronized(mInterfaceLock) {
+ int streamId = -1;
+ for (int i = 0; i < mConfiguredOutputs.size(); i++) {
+ if (surface == mConfiguredOutputs.valueAt(i).getSurface()) {
+ streamId = mConfiguredOutputs.keyAt(i);
+ break;
+ }
+ }
+ if (streamId == -1) {
+ throw new IllegalArgumentException("Surface is not part of this session");
+ }
+ try {
+ mRemoteDevice.tearDown(streamId);
+ } catch (CameraRuntimeException e) {
+ throw e.asChecked();
+ } catch (RemoteException e) {
+ // impossible
+ return;
+ }
+ }
+ }
+
public int capture(CaptureRequest request, CaptureCallback callback, Handler handler)
throws CameraAccessException {
if (DEBUG) {
diff --git a/core/java/android/hardware/camera2/legacy/CameraDeviceUserShim.java b/core/java/android/hardware/camera2/legacy/CameraDeviceUserShim.java
index f5314da..e20eaa7 100644
--- a/core/java/android/hardware/camera2/legacy/CameraDeviceUserShim.java
+++ b/core/java/android/hardware/camera2/legacy/CameraDeviceUserShim.java
@@ -636,6 +636,20 @@
return CameraBinderDecorator.NO_ERROR;
}
+ public int tearDown(int streamId) {
+ if (DEBUG) {
+ Log.d(TAG, "tearDown called.");
+ }
+ if (mLegacyDevice.isClosed()) {
+ Log.e(TAG, "Cannot tear down stream, device has been closed.");
+ return CameraBinderDecorator.ENODEV;
+ }
+
+ // LEGACY doesn't support actual teardown, so just a no-op
+
+ return CameraBinderDecorator.NO_ERROR;
+ }
+
@Override
public IBinder asBinder() {
// This is solely intended to be used for in-process binding.
