1 /* 2 * Copyright (C) 2017 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 EVS_VTS_FRAMEHANDLER_H 18 #define EVS_VTS_FRAMEHANDLER_H 19 20 #include <queue> 21 22 #include <android/hardware/automotive/evs/1.0/IEvsCameraStream.h> 23 #include <android/hardware/automotive/evs/1.0/IEvsCamera.h> 24 #include <android/hardware/automotive/evs/1.0/IEvsDisplay.h> 25 26 using namespace ::android::hardware::automotive::evs::V1_0; 27 using ::android::hardware::Return; 28 using ::android::hardware::Void; 29 using ::android::hardware::hidl_vec; 30 using ::android::hardware::hidl_handle; 31 using ::android::sp; 32 33 34 /* 35 * FrameHandler: 36 * This class can be used to receive camera imagery from an IEvsCamera implementation. Given an 37 * IEvsDisplay instance at startup, it will forward the received imagery to the display, 38 * providing a trivial implementation of a rear vew camera type application. 39 * Note that the video frames are delivered on a background thread, while the control interface 40 * is actuated from the applications foreground thread. 41 */ 42 class FrameHandler : public IEvsCameraStream { 43 public: 44 enum BufferControlFlag { 45 eAutoReturn, 46 eNoAutoReturn, 47 }; 48 49 FrameHandler(android::sp <IEvsCamera> pCamera, CameraDesc cameraInfo, 50 android::sp <IEvsDisplay> pDisplay = nullptr, 51 BufferControlFlag mode = eAutoReturn); 52 void shutdown(); 53 54 bool startStream(); 55 void asyncStopStream(); 56 void blockingStopStream(); 57 58 bool returnHeldBuffer(); 59 60 bool isRunning(); 61 62 void waitForFrameCount(unsigned frameCount); 63 void getFramesCounters(unsigned* received, unsigned* displayed); 64 void getFrameDimension(unsigned* width, unsigned* height); 65 66 private: 67 // Implementation for ::android::hardware::automotive::evs::V1_0::ICarCameraStream 68 Return<void> deliverFrame(const BufferDesc& buffer) override; 69 70 // Local implementation details 71 bool copyBufferContents(const BufferDesc& tgtBuffer, const BufferDesc& srcBuffer); 72 73 // Values initialized as startup 74 android::sp <IEvsCamera> mCamera; 75 CameraDesc mCameraInfo; 76 android::sp <IEvsDisplay> mDisplay; 77 BufferControlFlag mReturnMode; 78 79 // Since we get frames delivered to us asnchronously via the ICarCameraStream interface, 80 // we need to protect all member variables that may be modified while we're streaming 81 // (ie: those below) 82 std::mutex mLock; 83 std::condition_variable mSignal; 84 85 std::queue<BufferDesc> mHeldBuffers; 86 bool mRunning = false; 87 unsigned mFramesReceived = 0; // Simple counter -- rolls over eventually! 88 unsigned mFramesDisplayed = 0; // Simple counter -- rolls over eventually! 89 unsigned mFrameWidth = 0; 90 unsigned mFrameHeight = 0; 91 }; 92 93 94 #endif //EVS_VTS_FRAMEHANDLER_H 95