Add framework support for camcorder zoom.

The purpose of ICameraRecordingProxy and ICameraRecordingProxyListener is to
allow applications using the camera during recording.

Camera service allows only one client at a time. Since camcorder application
needs to own the camera to do things like zoom, the media recorder cannot
access the camera directly during recording. So ICameraRecordingProxy is a proxy
of ICamera, which allows the media recorder to start/stop the recording and
release recording frames. ICameraRecordingProxyListener is an interface that
allows the recorder to receive video frames during recording.

ICameraRecordingProxy
  startRecording()
  stopRecording()
  releaseRecordingFrame()

ICameraRecordingProxyListener
  dataCallbackTimestamp()

The camcorder app opens the camera and starts the preview. The app passes
ICamera and ICameraRecordingProxy to the media recorder by
MediaRecorder::setCamera(). The recorder uses ICamera to setup the camera in
MediaRecorder::start(). After setup, the recorder disconnects from camera
service. The recorder calls ICameraRecordingProxy::startRecording() and
passes a ICameraRecordingProxyListener to the app. The app connects back to
camera service and starts the recording. The app owns the camera and can do
things like zoom. The media recorder receives the video frames from the
listener and releases them by ICameraRecordingProxy::releaseRecordingFrame.
The recorder calls ICameraRecordingProxy::stopRecording() to stop the
recording.

The call sequences are as follows:
1. The app: Camera.unlock().
2. The app: MediaRecorder.setCamera().
3. Start recording
   (1) The app: MediaRecorder.start().
   (2) The recorder: ICamera.unlock() and ICamera.disconnect().
   (3) The recorder: ICameraRecordingProxy.startRecording().
   (4) The app: ICamera.reconnect().
   (5) The app: ICamera.startRecording().
4. During recording
   (1) The recorder: receive frames from ICameraRecordingProxyListener.dataCallbackTimestamp()
   (2) The recorder: release frames by ICameraRecordingProxy.releaseRecordingFrame().
5. Stop recording
   (1) The app: MediaRecorder.stop()
   (2) The recorder: ICameraRecordingProxy.stopRecording().
   (3) The app: ICamera.stopRecording().

bug:2644213

Change-Id: I15269397defc25cbbcae16abc071c8349c123122

1 files changed, 109 insertions, 0 deletions

diff --git a/camera/ICameraRecordingProxy.cpp b/camera/ICameraRecordingProxy.cpp
new file mode 100644
index 0000000..64b6a5c
--- /dev/null
+++ b/camera/ICameraRecordingProxy.cpp
@@ -0,0 +1,109 @@
+/*
+ * Copyright (C) 2011 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.
+ */
+
+//#define LOG_NDEBUG 0
+#define LOG_TAG "ICameraRecordingProxy"
+#include <camera/ICameraRecordingProxy.h>
+#include <camera/ICameraRecordingProxyListener.h>
+#include <binder/IMemory.h>
+#include <binder/Parcel.h>
+#include <stdint.h>
+#include <utils/Log.h>
+
+namespace android {
+
+enum {
+    START_RECORDING = IBinder::FIRST_CALL_TRANSACTION,
+    STOP_RECORDING,
+    RELEASE_RECORDING_FRAME,
+};
+
+
+class BpCameraRecordingProxy: public BpInterface<ICameraRecordingProxy>
+{
+public:
+    BpCameraRecordingProxy(const sp<IBinder>& impl)
+        : BpInterface<ICameraRecordingProxy>(impl)
+    {
+    }
+
+    status_t startRecording(const sp<ICameraRecordingProxyListener>& listener)
+    {
+        LOGV("startRecording");
+        Parcel data, reply;
+        data.writeInterfaceToken(ICameraRecordingProxy::getInterfaceDescriptor());
+        data.writeStrongBinder(listener->asBinder());
+        remote()->transact(START_RECORDING, data, &reply);
+        return reply.readInt32();
+    }
+
+    void stopRecording()
+    {
+        LOGV("stopRecording");
+        Parcel data, reply;
+        data.writeInterfaceToken(ICameraRecordingProxy::getInterfaceDescriptor());
+        remote()->transact(STOP_RECORDING, data, &reply);
+    }
+
+    void releaseRecordingFrame(const sp<IMemory>& mem)
+    {
+        LOGV("releaseRecordingFrame");
+        Parcel data, reply;
+        data.writeInterfaceToken(ICameraRecordingProxy::getInterfaceDescriptor());
+        data.writeStrongBinder(mem->asBinder());
+        remote()->transact(RELEASE_RECORDING_FRAME, data, &reply);
+    }
+};
+
+IMPLEMENT_META_INTERFACE(CameraRecordingProxy, "android.hardware.ICameraRecordingProxy");
+
+// ----------------------------------------------------------------------
+
+status_t BnCameraRecordingProxy::onTransact(
+    uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags)
+{
+    switch(code) {
+        case START_RECORDING: {
+            LOGV("START_RECORDING");
+            CHECK_INTERFACE(ICameraRecordingProxy, data, reply);
+            sp<ICameraRecordingProxyListener> listener =
+                interface_cast<ICameraRecordingProxyListener>(data.readStrongBinder());
+            reply->writeInt32(startRecording(listener));
+            return NO_ERROR;
+        } break;
+        case STOP_RECORDING: {
+            LOGV("STOP_RECORDING");
+            CHECK_INTERFACE(ICameraRecordingProxy, data, reply);
+            stopRecording();
+            return NO_ERROR;
+        } break;
+        case RELEASE_RECORDING_FRAME: {
+            LOGV("RELEASE_RECORDING_FRAME");
+            CHECK_INTERFACE(ICameraRecordingProxy, data, reply);
+            sp<IMemory> mem = interface_cast<IMemory>(data.readStrongBinder());
+            releaseRecordingFrame(mem);
+            return NO_ERROR;
+        } break;
+
+        default:
+            return BBinder::onTransact(code, data, reply, flags);
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+}; // namespace android
+