/**
 * Edge detection
 * 
 * 
 * @author Pat Troy: troy AT uic DOT edu
 */


import java.util.*;
import java.awt.*;

public class Lect1102e
{
  public static void main(String[] args)
  {
    // get the foreground picture
    String fileName = FileChooser.pickAFile();
    Picture pict = new Picture (fileName);
    
    // call a method to do the background/foreground separation
    Picture pictNew;
    pictNew = detectEdge (pict);
    pictNew.show();

  }
  
  
  public static Picture detectEdge (Picture p)
  {
    // set up the "background color"
    Color background = new Color (12, 48, 68);
    Picture result = new Picture (p.getWidth(), p.getHeight());
    
    Pixel pix, pix2, pixNew;
    int red, green, blue, grayAmount;
    Color c2;
    
    // set up two loops; one nested inside the other
    int xIndex, yIndex;
    
    for ( xIndex = 0 ; xIndex < p.getWidth()-1 ;  xIndex++ )
    {
      for ( yIndex = 0 ; yIndex < p.getHeight()-1 ; yIndex++ )
      {
        // Access the pixel from the orignal image
        pix = p.getPixel (xIndex, yIndex);
        pix2 = p.getPixel (xIndex + 1, yIndex);
        c2 = pix2.getColor();
            
        // check to see if the pixel's color is not close to the background color
        if ( pix.colorDistance (c2) > 45.0 )
          {
            //Access the pixl from the new background
            pixNew = result.getPixel (xIndex, yIndex);
          
            // set the 3 color values in the new pixel
            pixNew.setRed (0);
            pixNew.setGreen (0);
            pixNew.setBlue (0);

          }
        
        pix2 = p.getPixel (xIndex, yIndex+1);
        c2 = pix2.getColor();
            
        // check to see if the pixel's color is not close to the background color
        if ( pix.colorDistance (c2) > 45.0 )
          {
            //Access the pixl from the new background
            pixNew = result.getPixel (xIndex, yIndex);
          
            // set the 3 color values in the new pixel
            pixNew.setRed (0);
            pixNew.setGreen (0);
            pixNew.setBlue (0);

          }
      }
    }
    
    return ( result );
  }
  
}