/*
Threshold: extract 3D coordinates below a given grayscale value from a set of images

First Use:
    Compile with: javac Threshold.java

Use:
    java Threshold <startImgId> <endImgId> <ThresholdGrayscaleValue> > <outputFile>

    Copyright (C) 2008   Ruggero Scorcioni (rscorcio at gmu dot edu)

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

import java.awt.image.*;
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import java.lang.Math.*;

public class Threshold  {
    //set max output size
    public static final int MAXPOINT=10000;
    //thickness in pixel of each section
    public static final int ZJUMP=10;
    Image img;
    int imgX=0,imgY=0;
    int[] pixel;
    static int st,en,th;

    //return the color of pixel at coord x,y
    public  int pixelValue( int x, int y) {
	return pixel[x+imgX*y];
    }
    
    //load all pixels into the 'pixel' array
    public void readJPG(String name){
	int color;
	try {
	    img = Toolkit.getDefaultToolkit().getImage(name);
	    PixelGrabber grabber =  new PixelGrabber(img, 0, 0, -1, -1, false);
	    if (grabber.grabPixels()) {
                imgX = grabber.getWidth();
                imgY = grabber.getHeight();             
		pixel = (int[]) grabber.getPixels();
            }
	} catch (Exception e) {
	    System.err.println(e.getMessage());
	}
    }
    public void extractPixel(){
	int r,g,b,gr,alpha,c,count=0,ratio=0;

	//2 iterations: first to compute how many pixel available and 
	//              second to print
	for(int i=0;i<2;i++){

	    if(i==1){
		//at second iteration compute the correct sampling ratio
		ratio=count/MAXPOINT+1;
		if(ratio<=0){
		    ratio=1;
		}
	    }

	    
	    for(int l=st;l<=en;l++){
		
		System.err.print(l+" ");
		//load all pixel from one image
		readJPG("_oi7_aligned."+l+".png");
		
		for(int x=0;x<imgX;x++){
		    for(int y=0;y<imgY;y++){
			//extract color from coord x,y
			c=pixelValue(x,y);
			
			//decompose color code in RGB components
			r = (c >> 16) & 0xff;
			g = (c >> 8) & 0xff;
			b = c & 0xff;
			alpha = (c >> 24) & 0xff;
			
			//compute grayscale value
			gr=(int)(0.3*r+0.59*g+0.11*b);
			
			if(gr<th && gr >0){
			    count++;
			    //print 3D coord at correct sampling ratio at second iteration
			    if(i==1 && (count % ratio)==0){
				int z=l*ZJUMP;
				System.out.print(x+"\t"+y+"\t"+z+"\n");
			    }
			}
		    }
		}
	    }
	}
	
    }


    public static void main (String args[]) {
	String nam=args[0];
	String nam2=args[1];
	String nam3=args[2];
	
	//start # image
	st=new Integer(nam).intValue();
	//end # image
	en=new Integer(nam2).intValue();
	//Threshold value
	th=new Integer(nam3).intValue();
	

	Threshold t =new Threshold();
		
	t.extractPixel();

    }
}