content: package org.opencv.samples.imagemanipulations;
  
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  
  import org.opencv.android.BaseLoaderCallback;
  import org.opencv.android.CameraActivity;
  import org.opencv.android.CameraBridgeViewBase.CvCameraViewFrame;
  import org.opencv.android.LoaderCallbackInterface;
  import org.opencv.android.OpenCVLoader;
  import org.opencv.core.Core;
  import org.opencv.core.CvType;
  import org.opencv.core.Mat;
  import org.opencv.core.MatOfFloat;
  import org.opencv.core.MatOfInt;
  import org.opencv.core.Point;
  import org.opencv.core.Scalar;
  import org.opencv.core.Size;
  import org.opencv.android.CameraBridgeViewBase;
  import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener2;
  import org.opencv.imgproc.Imgproc;
  
  import android.os.Bundle;
  import android.util.Log;
  import android.view.Menu;
  import android.view.MenuItem;
  import android.view.WindowManager;
  
  public class ImageManipulationsActivity extends CameraActivity implements CvCameraViewListener2 {
      private static final String  TAG                 = "OCVSample::Activity";
  
      public static final int      VIEW_MODE_RGBA      = 0;
      public static final int      VIEW_MODE_HIST      = 1;
      public static final int      VIEW_MODE_CANNY     = 2;
      public static final int      VIEW_MODE_SEPIA     = 3;
      public static final int      VIEW_MODE_SOBEL     = 4;
      public static final int      VIEW_MODE_ZOOM      = 5;
      public static final int      VIEW_MODE_PIXELIZE  = 6;
      public static final int      VIEW_MODE_POSTERIZE = 7;
  
      private MenuItem             mItemPreviewRGBA;
      private MenuItem             mItemPreviewHist;
      private MenuItem             mItemPreviewCanny;
      private MenuItem             mItemPreviewSepia;
      private MenuItem             mItemPreviewSobel;
      private MenuItem             mItemPreviewZoom;
      private MenuItem             mItemPreviewPixelize;
      private MenuItem             mItemPreviewPosterize;
      private CameraBridgeViewBase mOpenCvCameraView;
  
      private Size                 mSize0;
  
      private Mat                  mIntermediateMat;
      private Mat                  mMat0;
      private MatOfInt             mChannels[];
      private MatOfInt             mHistSize;
      private int                  mHistSizeNum = 25;
      private MatOfFloat           mRanges;
      private Scalar               mColorsRGB[];
      private Scalar               mColorsHue[];
      private Scalar               mWhilte;
      private Point                mP1;
      private Point                mP2;
      private float                mBuff[];
      private Mat                  mSepiaKernel;
  
      public static int           viewMode = VIEW_MODE_RGBA;
  
      private BaseLoaderCallback  mLoaderCallback = new BaseLoaderCallback(this) {
          @Override
          public void onManagerConnected(int status) {
              switch (status) {
                  case LoaderCallbackInterface.SUCCESS:
                  {
                      Log.i(TAG, "OpenCV loaded successfully");
                      mOpenCvCameraView.enableView();
                  } break;
                  default:
                  {
                      super.onManagerConnected(status);
                  } break;
              }
          }
      };
  
      public ImageManipulationsActivity() {
          Log.i(TAG, "Instantiated new " + this.getClass());
      }
  
      /** Called when the activity is first created. */
      @Override
      public void onCreate(Bundle savedInstanceState) {
          Log.i(TAG, "called onCreate");
          super.onCreate(savedInstanceState);
          getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
  
          setContentView(R.layout.image_manipulations_surface_view);
  
          mOpenCvCameraView = (CameraBridgeViewBase) findViewById(R.id.image_manipulations_activity_surface_view);
          mOpenCvCameraView.setVisibility(CameraBridgeViewBase.VISIBLE);
          mOpenCvCameraView.setCvCameraViewListener(this);
      }
  
      @Override
      public void onPause()
      {
          super.onPause();
          if (mOpenCvCameraView != null)
              mOpenCvCameraView.disableView();
      }
  
      @Override
      public void onResume()
      {
          super.onResume();
          if (!OpenCVLoader.initDebug()) {
              Log.d(TAG, "Internal OpenCV library not found. Using OpenCV Manager for initialization");
              OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_3_0_0, this, mLoaderCallback);
          } else {
              Log.d(TAG, "OpenCV library found inside package. Using it!");
              mLoaderCallback.onManagerConnected(LoaderCallbackInterface.SUCCESS);
          }
      }
  
      @Override
      protected List<? extends CameraBridgeViewBase> getCameraViewList() {
          return Collections.singletonList(mOpenCvCameraView);
      }
  
      public void onDestroy() {
          super.onDestroy();
          if (mOpenCvCameraView != null)
              mOpenCvCameraView.disableView();
      }
  
      @Override
      public boolean onCreateOptionsMenu(Menu menu) {
          Log.i(TAG, "called onCreateOptionsMenu");
          mItemPreviewRGBA  = menu.add("Preview RGBA");
          mItemPreviewHist  = menu.add("Histograms");
          mItemPreviewCanny = menu.add("Canny");
          mItemPreviewSepia = menu.add("Sepia");
          mItemPreviewSobel = menu.add("Sobel");
          mItemPreviewZoom  = menu.add("Zoom");
          mItemPreviewPixelize  = menu.add("Pixelize");
          mItemPreviewPosterize = menu.add("Posterize");
          return true;
      }
  
      @Override
      public boolean onOptionsItemSelected(MenuItem item) {
          Log.i(TAG, "called onOptionsItemSelected; selected item: " + item);
          if (item == mItemPreviewRGBA)
              viewMode = VIEW_MODE_RGBA;
          if (item == mItemPreviewHist)
              viewMode = VIEW_MODE_HIST;
          else if (item == mItemPreviewCanny)
              viewMode = VIEW_MODE_CANNY;
          else if (item == mItemPreviewSepia)
              viewMode = VIEW_MODE_SEPIA;
          else if (item == mItemPreviewSobel)
              viewMode = VIEW_MODE_SOBEL;
          else if (item == mItemPreviewZoom)
              viewMode = VIEW_MODE_ZOOM;
          else if (item == mItemPreviewPixelize)
              viewMode = VIEW_MODE_PIXELIZE;
          else if (item == mItemPreviewPosterize)
              viewMode = VIEW_MODE_POSTERIZE;
          return true;
      }
  
      public void onCameraViewStarted(int width, int height) {
          mIntermediateMat = new Mat();
          mSize0 = new Size();
          mChannels = new MatOfInt[] { new MatOfInt(0), new MatOfInt(1), new MatOfInt(2) };
          mBuff = new float[mHistSizeNum];
          mHistSize = new MatOfInt(mHistSizeNum);
          mRanges = new MatOfFloat(0f, 256f);
          mMat0  = new Mat();
          mColorsRGB = new Scalar[] { new Scalar(200, 0, 0, 255), new Scalar(0, 200, 0, 255), new Scalar(0, 0, 200, 255) };
          mColorsHue = new Scalar[] {
                  new Scalar(255, 0, 0, 255),   new Scalar(255, 60, 0, 255),  new Scalar(255, 120, 0, 255), new Scalar(255, 180, 0, 255), new Scalar(255, 240, 0, 255),
                  new Scalar(215, 213, 0, 255), new Scalar(150, 255, 0, 255), new Scalar(85, 255, 0, 255),  new Scalar(20, 255, 0, 255),  new Scalar(0, 255, 30, 255),
                  new Scalar(0, 255, 85, 255),  new Scalar(0, 255, 150, 255), new Scalar(0, 255, 215, 255), new Scalar(0, 234, 255, 255), new Scalar(0, 170, 255, 255),
                  new Scalar(0, 120, 255, 255), new Scalar(0, 60, 255, 255),  new Scalar(0, 0, 255, 255),   new Scalar(64, 0, 255, 255),  new Scalar(120, 0, 255, 255),
                  new Scalar(180, 0, 255, 255), new Scalar(255, 0, 255, 255), new Scalar(255, 0, 215, 255), new Scalar(255, 0, 85, 255),  new Scalar(255, 0, 0, 255)
          };
          mWhilte = Scalar.all(255);
          mP1 = new Point();
          mP2 = new Point();
  
          // Fill sepia kernel
          mSepiaKernel = new Mat(4, 4, CvType.CV_32F);
          mSepiaKernel.put(0, 0, /* R */0.189f, 0.769f, 0.393f, 0f);
          mSepiaKernel.put(1, 0, /* G */0.168f, 0.686f, 0.349f, 0f);
          mSepiaKernel.put(2, 0, /* B */0.131f, 0.534f, 0.272f, 0f);
          mSepiaKernel.put(3, 0, /* A */0.000f, 0.000f, 0.000f, 1f);
      }
  
      public void onCameraViewStopped() {
          // Explicitly deallocate Mats
          if (mIntermediateMat != null)
              mIntermediateMat.release();
  
          mIntermediateMat = null;
      }
  
      public Mat onCameraFrame(CvCameraViewFrame inputFrame) {
          Mat rgba = inputFrame.rgba();
          Size sizeRgba = rgba.size();
  
          Mat rgbaInnerWindow;
  
          int rows = (int) sizeRgba.height;
          int cols = (int) sizeRgba.width;
  
          int left = cols / 8;
          int top = rows / 8;
  
          int width = cols * 3 / 4;
          int height = rows * 3 / 4;
  
          switch (ImageManipulationsActivity.viewMode) {
          case ImageManipulationsActivity.VIEW_MODE_RGBA:
              break;
  
          case ImageManipulationsActivity.VIEW_MODE_HIST:
              Mat hist = new Mat();
              int thikness = (int) (sizeRgba.width / (mHistSizeNum + 10) / 5);
              if(thikness > 5) thikness = 5;
              int offset = (int) ((sizeRgba.width - (5*mHistSizeNum + 4*10)*thikness)/2);
              // RGB
              for(int c=0; c<3; c++) {
                  Imgproc.calcHist(Arrays.asList(rgba), mChannels[c], mMat0, hist, mHistSize, mRanges);
                  Core.normalize(hist, hist, sizeRgba.height/2, 0, Core.NORM_INF);
                  hist.get(0, 0, mBuff);
                  for(int h=0; h<mHistSizeNum; h++) {
                      mP1.x = mP2.x = offset + (c * (mHistSizeNum + 10) + h) * thikness;
                      mP1.y = sizeRgba.height-1;
                      mP2.y = mP1.y - 2 - (int)mBuff[h];
                      Imgproc.line(rgba, mP1, mP2, mColorsRGB[c], thikness);
                  }
              }
              // Value and Hue
              Imgproc.cvtColor(rgba, mIntermediateMat, Imgproc.COLOR_RGB2HSV_FULL);
              // Value
              Imgproc.calcHist(Arrays.asList(mIntermediateMat), mChannels[2], mMat0, hist, mHistSize, mRanges);
              Core.normalize(hist, hist, sizeRgba.height/2, 0, Core.NORM_INF);
              hist.get(0, 0, mBuff);
              for(int h=0; h<mHistSizeNum; h++) {
                  mP1.x = mP2.x = offset + (3 * (mHistSizeNum + 10) + h) * thikness;
                  mP1.y = sizeRgba.height-1;
                  mP2.y = mP1.y - 2 - (int)mBuff[h];
                  Imgproc.line(rgba, mP1, mP2, mWhilte, thikness);
              }
              // Hue
              Imgproc.calcHist(Arrays.asList(mIntermediateMat), mChannels[0], mMat0, hist, mHistSize, mRanges);
              Core.normalize(hist, hist, sizeRgba.height/2, 0, Core.NORM_INF);
              hist.get(0, 0, mBuff);
              for(int h=0; h<mHistSizeNum; h++) {
                  mP1.x = mP2.x = offset + (4 * (mHistSizeNum + 10) + h) * thikness;
                  mP1.y = sizeRgba.height-1;
                  mP2.y = mP1.y - 2 - (int)mBuff[h];
                  Imgproc.line(rgba, mP1, mP2, mColorsHue[h], thikness);
              }
              break;
  
          case ImageManipulationsActivity.VIEW_MODE_CANNY:
              rgbaInnerWindow = rgba.submat(top, top + height, left, left + width);
              Imgproc.Canny(rgbaInnerWindow, mIntermediateMat, 80, 90);
              Imgproc.cvtColor(mIntermediateMat, rgbaInnerWindow, Imgproc.COLOR_GRAY2BGRA, 4);
              rgbaInnerWindow.release();
              break;
  
          case ImageManipulationsActivity.VIEW_MODE_SOBEL:
              Mat gray = inputFrame.gray();
              Mat grayInnerWindow = gray.submat(top, top + height, left, left + width);
              rgbaInnerWindow = rgba.submat(top, top + height, left, left + width);
              Imgproc.Sobel(grayInnerWindow, mIntermediateMat, CvType.CV_8U, 1, 1);
              Core.convertScaleAbs(mIntermediateMat, mIntermediateMat, 10, 0);
              Imgproc.cvtColor(mIntermediateMat, rgbaInnerWindow, Imgproc.COLOR_GRAY2BGRA, 4);
              grayInnerWindow.release();
              rgbaInnerWindow.release();
              break;
  
          case ImageManipulationsActivity.VIEW_MODE_SEPIA:
              rgbaInnerWindow = rgba.submat(top, top + height, left, left + width);
              Core.transform(rgbaInnerWindow, rgbaInnerWindow, mSepiaKernel);
              rgbaInnerWindow.release();
              break;
  
          case ImageManipulationsActivity.VIEW_MODE_ZOOM:
              Mat zoomCorner = rgba.submat(0, rows / 2 - rows / 10, 0, cols / 2 - cols / 10);
              Mat mZoomWindow = rgba.submat(rows / 2 - 9 * rows / 100, rows / 2 + 9 * rows / 100, cols / 2 - 9 * cols / 100, cols / 2 + 9 * cols / 100);
              Imgproc.resize(mZoomWindow, zoomCorner, zoomCorner.size(), 0, 0, Imgproc.INTER_LINEAR_EXACT);
              Size wsize = mZoomWindow.size();
              Imgproc.rectangle(mZoomWindow, new Point(1, 1), new Point(wsize.width - 2, wsize.height - 2), new Scalar(255, 0, 0, 255), 2);
              zoomCorner.release();
              mZoomWindow.release();
              break;
  
          case ImageManipulationsActivity.VIEW_MODE_PIXELIZE:
              rgbaInnerWindow = rgba.submat(top, top + height, left, left + width);
              Imgproc.resize(rgbaInnerWindow, mIntermediateMat, mSize0, 0.1, 0.1, Imgproc.INTER_NEAREST);
              Imgproc.resize(mIntermediateMat, rgbaInnerWindow, rgbaInnerWindow.size(), 0., 0., Imgproc.INTER_NEAREST);
              rgbaInnerWindow.release();
              break;
  
          case ImageManipulationsActivity.VIEW_MODE_POSTERIZE:
              /*
              Imgproc.cvtColor(rgbaInnerWindow, mIntermediateMat, Imgproc.COLOR_RGBA2RGB);
              Imgproc.pyrMeanShiftFiltering(mIntermediateMat, mIntermediateMat, 5, 50);
              Imgproc.cvtColor(mIntermediateMat, rgbaInnerWindow, Imgproc.COLOR_RGB2RGBA);
              */
              rgbaInnerWindow = rgba.submat(top, top + height, left, left + width);
              Imgproc.Canny(rgbaInnerWindow, mIntermediateMat, 80, 90);
              rgbaInnerWindow.setTo(new Scalar(0, 0, 0, 255), mIntermediateMat);
              Core.convertScaleAbs(rgbaInnerWindow, mIntermediateMat, 1./16, 0);
              Core.convertScaleAbs(mIntermediateMat, rgbaInnerWindow, 16, 0);
              rgbaInnerWindow.release();
              break;
          }
  
          return rgba;
      }
  }
  