1 /*
2  * Copyright (C) 2011 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ANDROID_HARDWARE_ICAMERA_RECORDING_PROXY_H
18 #define ANDROID_HARDWARE_ICAMERA_RECORDING_PROXY_H
19 
20 #include <vector>
21 #include <binder/IInterface.h>
22 #include <cutils/native_handle.h>
23 #include <utils/RefBase.h>
24 
25 namespace android {
26 
27 class Parcel;
28 
29 /*
30  * The purpose of ICameraRecordingProxy is to
31  * allow applications to use the camera during recording with the old camera API.
32  *
33  * Camera service allows only one client at a time. Since camcorder application
34  * needs to own the camera to do things like zoom, the media recorder cannot
35  * access the camera directly during recording. So ICameraRecordingProxy is a
36  * proxy of ICamera, which allows the media recorder to start/stop the recording
37  * and release recording frames. ICameraRecordingProxyListener is an interface
38  * that allows the recorder to receive video frames during recording.
39  *
40  * ICameraRecordingProxy
41  *   startRecording()
42  *   stopRecording()
43  *
44  * The camcorder app opens the camera and starts the preview. The app passes
45  * ICamera and ICameraRecordingProxy to the media recorder by
46  * MediaRecorder::setCamera(). The recorder uses ICamera to setup the camera in
47  * MediaRecorder::start(). After setup, the recorder disconnects from camera
48  * service. The recorder calls ICameraRecordingProxy::startRecording() and The
49  * app owns the camera and can do things like zoom. The media recorder receives
50  * the video frames via a buffer queue.  The recorder calls
51  * ICameraRecordingProxy::stopRecording() to stop the recording.
52  *
53  * The call sequences are as follows:
54  * 1. The app: Camera.unlock().
55  * 2. The app: MediaRecorder.setCamera().
56  * 3. Start recording
57  *    (1) The app: MediaRecorder.start().
58  *    (2) The recorder: ICamera.setVideoTarget(buffer queue).
59  *    (3) The recorder: ICamera.unlock() and ICamera.disconnect().
60  *    (4) The recorder: ICameraRecordingProxy.startRecording().
61  *    (5) The app: ICamera.reconnect().
62  *    (6) The app: ICamera.startRecording().
63  * 4. During recording
64  *    (1) The recorder: receive frames via a buffer queue
65  *    (2) The recorder: release frames via a buffer queue
66  * 5. Stop recording
67  *    (1) The app: MediaRecorder.stop()
68  *    (2) The recorder: ICameraRecordingProxy.stopRecording().
69  *    (3) The app: ICamera.stopRecording().
70  */
71 
72 class ICameraRecordingProxy: public IInterface
73 {
74 public:
75     DECLARE_META_INTERFACE(CameraRecordingProxy);
76 
77     virtual status_t        startRecording() = 0;
78     virtual void            stopRecording() = 0;
79 };
80 
81 // ----------------------------------------------------------------------------
82 
83 class BnCameraRecordingProxy: public BnInterface<ICameraRecordingProxy>
84 {
85 public:
86     virtual status_t    onTransact( uint32_t code,
87                                     const Parcel& data,
88                                     Parcel* reply,
89                                     uint32_t flags = 0);
90 };
91 
92 }; // namespace android
93 
94 #endif
95