| /* |
| * Copyright 2014, The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef VIDEO_FRAME_SCHEDULER_H_ |
| #define VIDEO_FRAME_SCHEDULER_H_ |
| |
| #include <utils/RefBase.h> |
| #include <utils/Timers.h> |
| |
| #include <media/stagefright/foundation/ABase.h> |
| |
| namespace android { |
| |
| struct ISurfaceComposer; |
| |
| struct VideoFrameScheduler : public RefBase { |
| VideoFrameScheduler(); |
| |
| // (re)initialize scheduler |
| void init(float videoFps = -1); |
| // use in case of video render-time discontinuity, e.g. seek |
| void restart(); |
| // get adjusted nanotime for a video frame render at renderTime |
| nsecs_t schedule(nsecs_t renderTime); |
| |
| // returns the vsync period for the main display |
| nsecs_t getVsyncPeriod(); |
| |
| void release(); |
| |
| static const size_t kHistorySize = 8; |
| |
| protected: |
| virtual ~VideoFrameScheduler(); |
| |
| private: |
| struct PLL { |
| PLL(); |
| |
| // reset PLL to new PLL |
| void reset(float fps = -1); |
| // keep current estimate, but restart phase |
| void restart(); |
| // returns period |
| nsecs_t addSample(nsecs_t time); |
| |
| private: |
| nsecs_t mPeriod; |
| nsecs_t mPhase; |
| |
| bool mPrimed; // have an estimate for the period |
| size_t mSamplesUsedForPriming; |
| |
| nsecs_t mLastTime; // last input time |
| nsecs_t mRefitAt; // next input time to fit at |
| |
| size_t mNumSamples; // can go past kHistorySize |
| nsecs_t mTimes[kHistorySize]; |
| |
| void test(); |
| // returns whether fit was successful |
| bool fit(nsecs_t phase, nsecs_t period, size_t numSamples, |
| int64_t *a, int64_t *b, int64_t *err); |
| void prime(size_t numSamples); |
| }; |
| |
| void updateVsync(); |
| |
| nsecs_t mVsyncTime; // vsync timing from display |
| nsecs_t mVsyncPeriod; |
| nsecs_t mVsyncRefreshAt; // next time to refresh timing info |
| |
| nsecs_t mLastVsyncTime; // estimated vsync time for last frame |
| nsecs_t mTimeCorrection; // running adjustment |
| |
| PLL mPll; // PLL for video frame rate based on render time |
| |
| sp<ISurfaceComposer> mComposer; |
| |
| DISALLOW_EVIL_CONSTRUCTORS(VideoFrameScheduler); |
| }; |
| |
| } // namespace android |
| |
| #endif // VIDEO_FRAME_SCHEDULER_H_ |
| |