调整拍照的实现，改成一个request实现测光和拍照

app/src/main/cpp/camera2/ndkcamera.h

@@ -202,6 +202,9 @@ public:
     static bool convertAImageToNv21(AImage* image, uint8_t** nv21, int32_t& width, int32_t& height);
     static void EnumCameraResult(ACameraMetadata* result, CAPTURE_RESULT& captureResult);
 
+protected:
+    void SetupMFNR(ACameraMetadata* characteristics, ACaptureRequest* request);
+
 protected:
     std::mutex m_locker;
     std::set<std::string> m_availableCameras;
@@ -258,33 +261,21 @@ protected:
     ACameraOutputTarget* mPreviewOutputTarget;
     ACaptureSessionOutput* mPreviewSessionOutput;
 
-    AImageReader* mImageReader;
-    ANativeWindow* mImageWindow;
-    ACameraOutputTarget* mOutputTarget;
-    ACaptureSessionOutput* mSessionOutput;
-
-    AImageReader* mImageReader2;
-    ANativeWindow* mImageWindow2;
-    ACameraOutputTarget* mOutputTarget2;
-    ACaptureSessionOutput* mSessionOutput2;
-
     std::shared_ptr<ACameraMetadata> mCharacteristics;
     std::vector<CaptureRequest*> mCaptureRequests;
 
     ACameraCaptureSession* capture_session;
 
-    std::shared_ptr<ACameraMetadata> mPreviewResults;
-    std::vector<std::shared_ptr<ACameraMetadata> > mCaptureResults;
     std::map<int64_t, std::shared_ptr<ACameraMetadata> > mCaptureResultMap;
     uint32_t mLdr;
     uint32_t mFinalLdr;
-    uint32_t mFinalBurstCaptures;
     int32_t mFinalOutputFormat;
     std::vector<std::shared_ptr<AImage> > mCaptureFrames;
 
     // cv::Mat mOneFrame;
     std::vector<std::pair<int64_t, cv::Mat> > mOneFrame;
     std::vector<std::vector<uint8_t> >  mRawFrames;
+    int64_t m_minTimestamp;
 
     // AImageReader* image_reader;
     // ANativeWindow* image_reader_surface;