ICameraRecordingProxy.h revision b5df547bce900fa5764d735bee304e79c001d60d 
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
25namespace android {
26
27class ICameraRecordingProxyListener;
28class IMemory;
29class Parcel;
30
31/*
32 * The purpose of ICameraRecordingProxy and ICameraRecordingProxyListener is to
33 * allow applications using the camera during recording.
34 *
35 * Camera service allows only one client at a time. Since camcorder application
36 * needs to own the camera to do things like zoom, the media recorder cannot
37 * access the camera directly during recording. So ICameraRecordingProxy is a
38 * proxy of ICamera, which allows the media recorder to start/stop the recording
39 * and release recording frames. ICameraRecordingProxyListener is an interface
40 * that allows the recorder to receive video frames during recording.
41 *
42 * ICameraRecordingProxy
43 *   startRecording()
44 *   stopRecording()
45 *   releaseRecordingFrame()
46 *
47 * ICameraRecordingProxyListener
48 *   dataCallbackTimestamp()
49
50 * The camcorder app opens the camera and starts the preview. The app passes
51 * ICamera and ICameraRecordingProxy to the media recorder by
52 * MediaRecorder::setCamera(). The recorder uses ICamera to setup the camera in
53 * MediaRecorder::start(). After setup, the recorder disconnects from camera
54 * service. The recorder calls ICameraRecordingProxy::startRecording() and
55 * passes a ICameraRecordingProxyListener to the app. The app connects back to
56 * camera service and starts the recording. The app owns the camera and can do
57 * things like zoom. The media recorder receives the video frames from the
58 * listener and releases them by ICameraRecordingProxy::releaseRecordingFrame.
59 * The recorder calls ICameraRecordingProxy::stopRecording() to stop the
60 * recording.
61 *
62 * The call sequences are as follows:
63 * 1. The app: Camera.unlock().
64 * 2. The app: MediaRecorder.setCamera().
65 * 3. Start recording
66 *    (1) The app: MediaRecorder.start().
67 *    (2) The recorder: ICamera.unlock() and ICamera.disconnect().
68 *    (3) The recorder: ICameraRecordingProxy.startRecording().
69 *    (4) The app: ICamera.reconnect().
70 *    (5) The app: ICamera.startRecording().
71 * 4. During recording
72 *    (1) The recorder: receive frames from ICameraRecordingProxyListener.dataCallbackTimestamp()
73 *    (2) The recorder: release frames by ICameraRecordingProxy.releaseRecordingFrame().
74 * 5. Stop recording
75 *    (1) The app: MediaRecorder.stop()
76 *    (2) The recorder: ICameraRecordingProxy.stopRecording().
77 *    (3) The app: ICamera.stopRecording().
78 */
79
80class ICameraRecordingProxy: public IInterface
81{
82public:
83    DECLARE_META_INTERFACE(CameraRecordingProxy);
84
85    virtual status_t        startRecording(const sp<ICameraRecordingProxyListener>& listener) = 0;
86    virtual void            stopRecording() = 0;
87    virtual void            releaseRecordingFrame(const sp<IMemory>& mem) = 0;
88    virtual void            releaseRecordingFrameHandle(native_handle_t *handle) = 0;
89    virtual void            releaseRecordingFrameHandleBatch(
90                                    const std::vector<native_handle_t*>& handles) = 0;
91};
92
93// ----------------------------------------------------------------------------
94
95class BnCameraRecordingProxy: public BnInterface<ICameraRecordingProxy>
96{
97public:
98    virtual status_t    onTransact( uint32_t code,
99                                    const Parcel& data,
100                                    Parcel* reply,
101                                    uint32_t flags = 0);
102};
103
104}; // namespace android
105
106#endif
107