public class MyGrayProgram {
   public static void main(String[] args) throws Exception{
      int[][] original = GrayImage.read("mushroom.jpeg");
      //int[][] manipulated = upDown(original);
      //int[][] manipulated = leftRight(original);
      //int[][] manipulated = invert(original);
      //int[][] manipulated = toBlackWhite(original);
      int[][] manipulated = contour(original);
      GrayImage.write("contourGray.jpeg", manipulated);
      GrayImageWindow iw = new GrayImageWindow(original, manipulated);
   }//main

   public static int[][] upDown(int[][] samples) {
      int[][] newSamples = new int[samples.length][samples[0].length];
      for (int row = 0; row < samples.length; row = row + 1)
         for (int col = 0; col < samples[row].length; col = col + 1)
            newSamples[row][col] = samples[samples.length - row - 1 ][col];
      return newSamples;
   }//upDown
   //Before:Grå bild
   //Afer:Bilden flippas runt y-axeln
   public static int[][] leftRight(int[][] samples) {
      int[][] flippedSample = new int[samples.length][samples[0].length];
      for (int row = 0; row < samples.length; row++)
         for (int col = 0; col < samples[row].length; col++) {
            flippedSample[row][col] = samples[row][samples[0].length - col -1];
         }
      return flippedSample;
   }
   //Before:Grå bild
   //After: Bilden tar 255 och subtraherar nuvarande gråskala och resultat ger en inverterad bild
   public static int[][] invert(int[][] samples) {
      int[][] invertedSample = new int[samples.length][samples[0].length];
      for (int row = 0; row < samples.length; row++)
         for (int col = 0; col < samples[row].length; col++)
            invertedSample[row][col] = 255- samples[row][col];
      return invertedSample;
   }

   //Before:En grå bild
   //After:Sätter alla gråa värden störer 128 till vit och alla värden under 128 till svart
   public static int[][] toBlackWhite(int[][] samples){
      int[][] blackWhiteSample = new int[samples.length][samples[0].length];
      for (int row = 0; row < samples.length; row++)
         for (int col = 0; col < samples[row].length; col++){
            if(samples[row][col] >= 128) {
               blackWhiteSample[row][col] = 255;
            }else{
               blackWhiteSample[row][col] = 0;
            }
         }
      return blackWhiteSample;
   }
   //Before:en grå bild
   //After:Letar efter grannar och gör alla "kanter" svarta och resten vitt
   //en pixel ska vara svart om och endast om orginal pixeln är svart och ligger på randen eller har en vit granne.
   public static int[][]contour(int[][] samples) {
      int[][] contourSample = new int[samples.length][samples[0].length];
      for (int row = 0; row < samples.length; row++) {
         for (int col = 0; col < samples[row].length; col++) {
            contourSample[row][col] = 255;
            if ((samples[row][col] < 128)) {
               if (col == 0 || col == samples[0].length - 1 || row == 0 || row == samples.length - 1)
                  contourSample[row][col] = 0;

               //}
               if(!(col == 0 || col == samples[0].length - 1 || row == 0 || row == samples.length - 1))
                  for (int r = -1; r < 2; r++) {
                     for (int c = -1; c < 2; c++) {
                        if (samples[row - r][col - c] >= 128) {
                           contourSample[row][col] = 0;
                        }
                     }
                  }
            }
         }
      }
      return contourSample;
   } //contour



}//MyGrayProgram