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, 101 insertions, 0 deletions

diff --git a/include/camera/ICameraRecordingProxy.h b/include/camera/ICameraRecordingProxy.h
new file mode 100644
index 0000000..2aac284
--- /dev/null
+++ b/include/camera/ICameraRecordingProxy.h
@@ -0,0 +1,101 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_HARDWARE_ICAMERA_RECORDING_PROXY_H
+#define ANDROID_HARDWARE_ICAMERA_RECORDING_PROXY_H
+
+#include <binder/IInterface.h>
+#include <utils/RefBase.h>
+
+namespace android {
+
+class ICameraRecordingProxyListener;
+class IMemory;
+class Parcel;
+
+/*
+ * 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().
+ */
+
+class ICameraRecordingProxy: public IInterface
+{
+public:
+    DECLARE_META_INTERFACE(CameraRecordingProxy);
+
+    virtual status_t        startRecording(const sp<ICameraRecordingProxyListener>& listener) = 0;
+    virtual void            stopRecording() = 0;
+    virtual void            releaseRecordingFrame(const sp<IMemory>& mem) = 0;
+};
+
+// ----------------------------------------------------------------------------
+
+class BnCameraRecordingProxy: public BnInterface<ICameraRecordingProxy>
+{
+public:
+    virtual status_t    onTransact( uint32_t code,
+                                    const Parcel& data,
+                                    Parcel* reply,
+                                    uint32_t flags = 0);
+};
+
+}; // namespace android
+
+#endif