CameraSourceTimeLapse.h revision 40e2f3f9b41f44bdb59f7708a421b87f169a6ede 
1/*
2 * Copyright (C) 2010 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 CAMERA_SOURCE_TIME_LAPSE_H_
18
19#define CAMERA_SOURCE_TIME_LAPSE_H_
20
21#include <pthread.h>
22
23#include <utils/RefBase.h>
24#include <utils/threads.h>
25
26namespace android {
27
28class ICamera;
29class IMemory;
30class Camera;
31
32class CameraSourceTimeLapse : public CameraSource {
33public:
34    static CameraSourceTimeLapse *Create(bool useStillCameraForTimeLapse,
35        int64_t timeBetweenTimeLapseFrameCaptureUs,
36        int32_t width, int32_t height,
37        int32_t videoFrameRate);
38
39    static CameraSourceTimeLapse *CreateFromCamera(const sp<Camera> &camera,
40        bool useStillCameraForTimeLapse,
41        int64_t timeBetweenTimeLapseFrameCaptureUs,
42        int32_t width, int32_t height,
43        int32_t videoFrameRate);
44
45    virtual ~CameraSourceTimeLapse();
46
47private:
48    // If true, will use still camera takePicture() for time lapse frames
49    // If false, will use the videocamera frames instead.
50    bool mUseStillCameraForTimeLapse;
51
52    // Size of picture taken from still camera. This may be larger than the size
53    // of the video, as still camera may not support the exact video resolution
54    // demanded. See setPictureSizeToClosestSupported().
55    int32_t mPictureWidth;
56    int32_t mPictureHeight;
57
58    // size of the encoded video.
59    int32_t mVideoWidth;
60    int32_t mVideoHeight;
61
62    // True if we need to crop the still camera image to get the video frame.
63    bool mNeedCropping;
64
65    // Start location of the cropping rectangle.
66    int32_t mCropRectStartX;
67    int32_t mCropRectStartY;
68
69    // Time between capture of two frames during time lapse recording
70    // Negative value indicates that timelapse is disabled.
71    int64_t mTimeBetweenTimeLapseFrameCaptureUs;
72
73    // Time between two frames in final video (1/frameRate)
74    int64_t mTimeBetweenTimeLapseVideoFramesUs;
75
76    // Real timestamp of the last encoded time lapse frame
77    int64_t mLastTimeLapseFrameRealTimestampUs;
78
79    // Thread id of thread which takes still picture and sleeps in a loop.
80    pthread_t mThreadTimeLapse;
81
82    // Variable set in dataCallbackTimestamp() to help skipCurrentFrame()
83    // to know if current frame needs to be skipped.
84    bool mSkipCurrentFrame;
85
86    // True if camera is in preview mode and ready for takePicture().
87    bool mCameraIdle;
88
89    CameraSourceTimeLapse(const sp<Camera> &camera,
90        bool useStillCameraForTimeLapse,
91        int64_t timeBetweenTimeLapseFrameCaptureUs,
92        int32_t width, int32_t height,
93        int32_t videoFrameRate);
94
95    // For still camera case starts a thread which calls camera's takePicture()
96    // in a loop. For video camera case, just starts the camera's video recording.
97    virtual void startCameraRecording();
98
99    // For still camera case joins the thread created in startCameraRecording().
100    // For video camera case, just stops the camera's video recording.
101    virtual void stopCameraRecording();
102
103    // For still camera case don't need to do anything as memory is locally
104    // allocated with refcounting.
105    // For video camera case just tell the camera to release the frame.
106    virtual void releaseRecordingFrame(const sp<IMemory>& frame);
107
108    // mSkipCurrentFrame is set to true in dataCallbackTimestamp() if the current
109    // frame needs to be skipped and this function just returns the value of mSkipCurrentFrame.
110    virtual bool skipCurrentFrame(int64_t timestampUs);
111
112    // Handles the callback to handle raw frame data from the still camera.
113    // Creates a copy of the frame data as the camera can reuse the frame memory
114    // once this callback returns. The function also sets a new timstamp corresponding
115    // to one frame time ahead of the last encoded frame's time stamp. It then
116    // calls dataCallbackTimestamp() of the base class with the copied data and the
117    // modified timestamp, which will think that it recieved the frame from a video
118    // camera and proceed as usual.
119    virtual void dataCallback(int32_t msgType, const sp<IMemory> &data);
120
121    // In the video camera case calls skipFrameAndModifyTimeStamp() to modify
122    // timestamp and set mSkipCurrentFrame.
123    // Then it calls the base CameraSource::dataCallbackTimestamp()
124    virtual void dataCallbackTimestamp(int64_t timestampUs, int32_t msgType,
125            const sp<IMemory> &data);
126
127    // The still camera may not support the demanded video width and height.
128    // We look for the supported picture sizes from the still camera and
129    // choose the smallest one with either dimensions higher than the corresponding
130    // video dimensions. The still picture will be cropped to get the video frame.
131    // The function returns true if the camera supports picture sizes greater than
132    // or equal to the passed in width and height, and false otherwise.
133    bool setPictureSizeToClosestSupported(int32_t width, int32_t height);
134
135    // Computes the offset of the rectangle from where to start cropping the
136    // still image into the video frame. We choose the center of the image to be
137    // cropped. The offset is stored in (mCropRectStartX, mCropRectStartY).
138    bool computeCropRectangleOffset();
139
140    // Crops the source data into a smaller image starting at
141    // (mCropRectStartX, mCropRectStartY) and of the size of the video frame.
142    // The data is returned into a newly allocated IMemory.
143    sp<IMemory> cropYUVImage(const sp<IMemory> &source_data);
144
145    // When video camera is used for time lapse capture, returns true
146    // until enough time has passed for the next time lapse frame. When
147    // the frame needs to be encoded, it returns false and also modifies
148    // the time stamp to be one frame time ahead of the last encoded
149    // frame's time stamp.
150    bool skipFrameAndModifyTimeStamp(int64_t *timestampUs);
151
152    // Wrapper to enter threadTimeLapseEntry()
153    static void *ThreadTimeLapseWrapper(void *me);
154
155    // Runs a loop which sleeps until a still picture is required
156    // and then calls mCamera->takePicture() to take the still picture.
157    // Used only in the case mUseStillCameraForTimeLapse = true.
158    void threadTimeLapseEntry();
159
160    // Wrapper to enter threadStartPreview()
161    static void *ThreadStartPreviewWrapper(void *me);
162
163    // Starts the camera's preview.
164    void threadStartPreview();
165
166    // Starts thread ThreadStartPreviewWrapper() for restarting preview.
167    // Needs to be done in a thread so that dataCallback() which calls this function
168    // can return, and the camera can know that takePicture() is done.
169    void restartPreview();
170
171    // Creates a copy of source_data into a new memory of final type MemoryBase.
172    sp<IMemory> createIMemoryCopy(const sp<IMemory> &source_data);
173
174    CameraSourceTimeLapse(const CameraSourceTimeLapse &);
175    CameraSourceTimeLapse &operator=(const CameraSourceTimeLapse &);
176};
177
178}  // namespace android
179
180#endif  // CAMERA_SOURCE_TIME_LAPSE_H_
181