SurfaceMediaSource.h revision 66e72bc85fb762876baff60ef29de729da93cf26
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_GUI_SURFACEMEDIASOURCE_H 18#define ANDROID_GUI_SURFACEMEDIASOURCE_H 19 20#include <gui/ISurfaceTexture.h> 21#include <gui/BufferQueue.h> 22 23#include <utils/threads.h> 24#include <utils/Vector.h> 25#include <media/stagefright/MediaSource.h> 26#include <media/stagefright/MediaBuffer.h> 27 28namespace android { 29// ---------------------------------------------------------------------------- 30 31class IGraphicBufferAlloc; 32class String8; 33class GraphicBuffer; 34 35// ASSUMPTIONS 36// 1. SurfaceMediaSource is initialized with width*height which 37// can never change. However, deqeueue buffer does not currently 38// enforce this as in BufferQueue, dequeue can be used by SurfaceTexture 39// which can modify the default width and heght. Also neither the width 40// nor height can be 0. 41// 2. setSynchronousMode is never used (basically no one should call 42// setSynchronousMode(false) 43// 3. setCrop, setTransform, setScalingMode should never be used 44// 4. queueBuffer returns a filled buffer to the SurfaceMediaSource. In addition, a 45// timestamp must be provided for the buffer. The timestamp is in 46// nanoseconds, and must be monotonically increasing. Its other semantics 47// (zero point, etc) are client-dependent and should be documented by the 48// client. 49// 5. Once disconnected, SurfaceMediaSource can be reused (can not 50// connect again) 51// 6. Stop is a hard stop, the last few frames held by the encoder 52// may be dropped. It is possible to wait for the buffers to be 53// returned (but not implemented) 54 55class SurfaceMediaSource : public MediaSource, 56 public MediaBufferObserver, 57 protected BufferQueue::ConsumerListener { 58public: 59 enum { MIN_UNDEQUEUED_BUFFERS = 4}; 60 61 struct FrameAvailableListener : public virtual RefBase { 62 // onFrameAvailable() is called from queueBuffer() is the FIFO is 63 // empty. You can use SurfaceMediaSource::getQueuedCount() to 64 // figure out if there are more frames waiting. 65 // This is called without any lock held can be called concurrently by 66 // multiple threads. 67 virtual void onFrameAvailable() = 0; 68 }; 69 70 SurfaceMediaSource(uint32_t bufferWidth, uint32_t bufferHeight); 71 72 virtual ~SurfaceMediaSource(); 73 74 // For the MediaSource interface for use by StageFrightRecorder: 75 virtual status_t start(MetaData *params = NULL); 76 virtual status_t stop(); 77 virtual status_t read(MediaBuffer **buffer, 78 const ReadOptions *options = NULL); 79 virtual sp<MetaData> getFormat(); 80 81 // Get / Set the frame rate used for encoding. Default fps = 30 82 status_t setFrameRate(int32_t fps) ; 83 int32_t getFrameRate( ) const; 84 85 // The call for the StageFrightRecorder to tell us that 86 // it is done using the MediaBuffer data so that its state 87 // can be set to FREE for dequeuing 88 virtual void signalBufferReturned(MediaBuffer* buffer); 89 // end of MediaSource interface 90 91 // getTimestamp retrieves the timestamp associated with the image 92 // set by the most recent call to read() 93 // 94 // The timestamp is in nanoseconds, and is monotonically increasing. Its 95 // other semantics (zero point, etc) are source-dependent and should be 96 // documented by the source. 97 int64_t getTimestamp(); 98 99 // setFrameAvailableListener sets the listener object that will be notified 100 // when a new frame becomes available. 101 void setFrameAvailableListener(const sp<FrameAvailableListener>& listener); 102 103 // dump our state in a String 104 void dump(String8& result) const; 105 void dump(String8& result, const char* prefix, char* buffer, 106 size_t SIZE) const; 107 108 // isMetaDataStoredInVideoBuffers tells the encoder whether we will 109 // pass metadata through the buffers. Currently, it is force set to true 110 bool isMetaDataStoredInVideoBuffers() const; 111 112 sp<BufferQueue> getBufferQueue() const { return mBufferQueue; } 113 114 // To be called before start() 115 status_t setMaxAcquiredBufferCount(size_t count); 116 117protected: 118 119 // Implementation of the BufferQueue::ConsumerListener interface. These 120 // calls are used to notify the SurfaceTexture of asynchronous events in the 121 // BufferQueue. 122 virtual void onFrameAvailable(); 123 124 // Used as a hook to BufferQueue::disconnect() 125 // This is called by the client side when it is done 126 // TODO: Currently, this also sets mStopped to true which 127 // is needed for unblocking the encoder which might be 128 // waiting to read more frames. So if on the client side, 129 // the same thread supplies the frames and also calls stop 130 // on the encoder, the client has to call disconnect before 131 // it calls stop. 132 // In the case of the camera, 133 // that need not be required since the thread supplying the 134 // frames is separate than the one calling stop. 135 virtual void onBuffersReleased(); 136 137 static bool isExternalFormat(uint32_t format); 138 139private: 140 // mBufferQueue is the exchange point between the producer and 141 // this consumer 142 sp<BufferQueue> mBufferQueue; 143 144 // mBufferSlot caches GraphicBuffers from the buffer queue 145 sp<GraphicBuffer> mBufferSlot[BufferQueue::NUM_BUFFER_SLOTS]; 146 147 148 // The permenent width and height of SMS buffers 149 int mWidth; 150 int mHeight; 151 152 // mCurrentSlot is the buffer slot index of the buffer that is currently 153 // being used by buffer consumer 154 // (e.g. StageFrightRecorder in the case of SurfaceMediaSource or GLTexture 155 // in the case of SurfaceTexture). 156 // It is initialized to INVALID_BUFFER_SLOT, 157 // indicating that no buffer slot is currently bound to the texture. Note, 158 // however, that a value of INVALID_BUFFER_SLOT does not necessarily mean 159 // that no buffer is bound to the texture. A call to setBufferCount will 160 // reset mCurrentTexture to INVALID_BUFFER_SLOT. 161 int mCurrentSlot; 162 163 // mCurrentBuffers is a list of the graphic buffers that are being used by 164 // buffer consumer (i.e. the video encoder). It's possible that these 165 // buffers are not associated with any buffer slots, so we must track them 166 // separately. Buffers are added to this list in read, and removed from 167 // this list in signalBufferReturned 168 Vector<sp<GraphicBuffer> > mCurrentBuffers; 169 170 // mCurrentTimestamp is the timestamp for the current texture. It 171 // gets set to mLastQueuedTimestamp each time updateTexImage is called. 172 int64_t mCurrentTimestamp; 173 174 // mFrameAvailableListener is the listener object that will be called when a 175 // new frame becomes available. If it is not NULL it will be called from 176 // queueBuffer. 177 sp<FrameAvailableListener> mFrameAvailableListener; 178 179 // mMutex is the mutex used to prevent concurrent access to the member 180 // variables of SurfaceMediaSource objects. It must be locked whenever the 181 // member variables are accessed. 182 mutable Mutex mMutex; 183 184 ////////////////////////// For MediaSource 185 // Set to a default of 30 fps if not specified by the client side 186 int32_t mFrameRate; 187 188 // mStopped is a flag to check if the recording is going on 189 bool mStopped; 190 191 // mNumFramesReceived indicates the number of frames recieved from 192 // the client side 193 int mNumFramesReceived; 194 // mNumFramesEncoded indicates the number of frames passed on to the 195 // encoder 196 int mNumFramesEncoded; 197 198 // mFirstFrameTimestamp is the timestamp of the first received frame. 199 // It is used to offset the output timestamps so recording starts at time 0. 200 int64_t mFirstFrameTimestamp; 201 // mStartTimeNs is the start time passed into the source at start, used to 202 // offset timestamps. 203 int64_t mStartTimeNs; 204 205 // mFrameAvailableCondition condition used to indicate whether there 206 // is a frame available for dequeuing 207 Condition mFrameAvailableCondition; 208 209 // Avoid copying and equating and default constructor 210 DISALLOW_IMPLICIT_CONSTRUCTORS(SurfaceMediaSource); 211}; 212 213// ---------------------------------------------------------------------------- 214}; // namespace android 215 216#endif // ANDROID_GUI_SURFACEMEDIASOURCE_H 217