SurfaceMediaSource.h revision 2cd25a9056cc150b9fd3ac9b0bca37a1334ffd47
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 77 virtual status_t stop() { return reset(); } 78 virtual status_t read( 79 MediaBuffer **buffer, const ReadOptions *options = NULL); 80 virtual sp<MetaData> getFormat(); 81 82 // Get / Set the frame rate used for encoding. Default fps = 30 83 status_t setFrameRate(int32_t fps) ; 84 int32_t getFrameRate( ) const; 85 86 // The call for the StageFrightRecorder to tell us that 87 // it is done using the MediaBuffer data so that its state 88 // can be set to FREE for dequeuing 89 virtual void signalBufferReturned(MediaBuffer* buffer); 90 // end of MediaSource interface 91 92 // getTimestamp retrieves the timestamp associated with the image 93 // set by the most recent call to read() 94 // 95 // The timestamp is in nanoseconds, and is monotonically increasing. Its 96 // other semantics (zero point, etc) are source-dependent and should be 97 // documented by the source. 98 int64_t getTimestamp(); 99 100 // setFrameAvailableListener sets the listener object that will be notified 101 // when a new frame becomes available. 102 void setFrameAvailableListener(const sp<FrameAvailableListener>& listener); 103 104 // dump our state in a String 105 void dump(String8& result) const; 106 void dump(String8& result, const char* prefix, char* buffer, 107 size_t SIZE) const; 108 109 // isMetaDataStoredInVideoBuffers tells the encoder whether we will 110 // pass metadata through the buffers. Currently, it is force set to true 111 bool isMetaDataStoredInVideoBuffers() const; 112 113 sp<BufferQueue> getBufferQueue() const { return mBufferQueue; } 114 115protected: 116 117 // Implementation of the BufferQueue::ConsumerListener interface. These 118 // calls are used to notify the SurfaceTexture of asynchronous events in the 119 // BufferQueue. 120 virtual void onFrameAvailable(); 121 122 // Used as a hook to BufferQueue::disconnect() 123 // This is called by the client side when it is done 124 // TODO: Currently, this also sets mStopped to true which 125 // is needed for unblocking the encoder which might be 126 // waiting to read more frames. So if on the client side, 127 // the same thread supplies the frames and also calls stop 128 // on the encoder, the client has to call disconnect before 129 // it calls stop. 130 // In the case of the camera, 131 // that need not be required since the thread supplying the 132 // frames is separate than the one calling stop. 133 virtual void onBuffersReleased(); 134 135 static bool isExternalFormat(uint32_t format); 136 137private: 138 // mBufferQueue is the exchange point between the producer and 139 // this consumer 140 sp<BufferQueue> mBufferQueue; 141 142 // mBufferSlot caches GraphicBuffers from the buffer queue 143 sp<GraphicBuffer> mBufferSlot[BufferQueue::NUM_BUFFER_SLOTS]; 144 145 146 // The permenent width and height of SMS buffers 147 int mWidth; 148 int mHeight; 149 150 // mCurrentSlot is the buffer slot index of the buffer that is currently 151 // being used by buffer consumer 152 // (e.g. StageFrightRecorder in the case of SurfaceMediaSource or GLTexture 153 // in the case of SurfaceTexture). 154 // It is initialized to INVALID_BUFFER_SLOT, 155 // indicating that no buffer slot is currently bound to the texture. Note, 156 // however, that a value of INVALID_BUFFER_SLOT does not necessarily mean 157 // that no buffer is bound to the texture. A call to setBufferCount will 158 // reset mCurrentTexture to INVALID_BUFFER_SLOT. 159 int mCurrentSlot; 160 161 // mCurrentBuffers is a list of the graphic buffers that are being used by 162 // buffer consumer (i.e. the video encoder). It's possible that these 163 // buffers are not associated with any buffer slots, so we must track them 164 // separately. Buffers are added to this list in read, and removed from 165 // this list in signalBufferReturned 166 Vector<sp<GraphicBuffer> > mCurrentBuffers; 167 168 // mCurrentTimestamp is the timestamp for the current texture. It 169 // gets set to mLastQueuedTimestamp each time updateTexImage is called. 170 int64_t mCurrentTimestamp; 171 172 // mFrameAvailableListener is the listener object that will be called when a 173 // new frame becomes available. If it is not NULL it will be called from 174 // queueBuffer. 175 sp<FrameAvailableListener> mFrameAvailableListener; 176 177 // mMutex is the mutex used to prevent concurrent access to the member 178 // variables of SurfaceMediaSource objects. It must be locked whenever the 179 // member variables are accessed. 180 mutable Mutex mMutex; 181 182 ////////////////////////// For MediaSource 183 // Set to a default of 30 fps if not specified by the client side 184 int32_t mFrameRate; 185 186 // mStopped is a flag to check if the recording is going on 187 bool mStopped; 188 189 // mNumFramesReceived indicates the number of frames recieved from 190 // the client side 191 int mNumFramesReceived; 192 // mNumFramesEncoded indicates the number of frames passed on to the 193 // encoder 194 int mNumFramesEncoded; 195 196 // mFirstFrameTimestamp is the timestamp of the first received frame. 197 // It is used to offset the output timestamps so recording starts at time 0. 198 int64_t mFirstFrameTimestamp; 199 // mStartTimeNs is the start time passed into the source at start, used to 200 // offset timestamps. 201 int64_t mStartTimeNs; 202 203 // mFrameAvailableCondition condition used to indicate whether there 204 // is a frame available for dequeuing 205 Condition mFrameAvailableCondition; 206 207 status_t reset(); 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