Computer Program Issues

[Platanum]

Any help would be appreciated, this project is fustrating me. Has to do with PGM image files, but really the problem in my code (I would assume, lies within my pointers and dynamically allocating memory).

Any help would be appreciated.

Code:
(main.cpp)

#include <cstdlib>
#include <iostream>
#include <string>

using namespace std;

#include "pgm.h"

int main(int argc, char *argv[])
{
	cout << "number of command line parameters: "<<argc<<endl;
    for (int i=0;i<argc;i++)
    {
        cout << i << ' ' << argv[i] << endl;
    }
    
        // here's how to put them into strings:
    string words[10];
    for (int i=0;i<min(10, argc); i++)
        words[i] = argv[i];
    cout << "the command line was:"<<endl;
    for (int i=0;i<min(10, argc); i++)
        cout << words[i]<<' ';
    cout << endl<<endl;
	
	string raw, dark, flat, outname;
	    PGM r;
	    PGM d;
	    PGM f;
	    PGM final;
	    PGM lin;
	    PGM log; 
	    
	    cout << "raw? " << endl;
	    getline(cin, raw);
	    cout << "dark? " << endl;
	    getline(cin, dark);
	    cout << "flat? " << endl;
	    getline(cin, flat);
	    cout << "outputname?" << endl;
	    getline(cin, outname);
	    
	    try
	    {
	    //read each file, return error if dont exsist.
	    cout << "Reading files..." << endl;
	  	readPGM(raw, r);
	    cout << "Raw Read" << endl;
	    readPGM(dark, d);
	    cout << "Dark Read" << endl;
	    readPGM(flat, f);
	    cout << "Flat Read" << endl;
	       
	    cout << endl << "Processing Final Image..." << endl;
	    processPGM(r, d, f, final);
	    dividePGM(final, d);
	    cout << "File Processed" << endl;
	    
	    cout << "Scaleing Final Image..." << endl;
	    //stupid function to get mv
	  	double mv = getMV(r);
	    //Scale final image linearly
	    cout << "Stretching linear..." << endl;
	  	stretch(final, lin, 0, mv, 0, 255);
	  	cout << "Writing linear..." << endl;
	    writePGM(outname, lin);
	    
	    //Scale final image log
	    cout << "Stretching log..." << endl;
	    stretch(final, log, 0, mv, 0, 255, LOGSCALE);
	    cout << "Writing log..." << endl;
	    writePGM(outname, log);
	    } 
	       
	   catch (string e)
	    {
	        cout << "Problem: "<<e<<endl;
	    }
	    
	   #ifdef WIN32
	   system("PAUSE");
	   #endif
	   return EXIT_SUCCESS;
}

(pgm.h)

#ifndef _SAMPLE_PGM_H_
#define _SAMPLE_PGM_H_
//  this should all be in a namespace!

struct PGM
{
	double *pix;
	int nc;
	int nr;
	string type;
	string comments;
	double mv;
	
	//PGM();
  //PGM(int size, int initval=0);
		
};

void readPGM(string filename, PGM &);
void writePGM(string filename, PGM &);
void stretch(PGM &sf, PGM &sl, double in_min, double in_max, double out_min, double out_max, 
			bool do_logscale = false);
void processPGM(PGM r, PGM d, PGM f, PGM &final);
void dividePGM(PGM &final, PGM d);
double getMV(PGM &r);

enum STUFF{LINEAR=false, LOGSCALE=true};
#endif

(pgm.cpp)

#include <iostream>
#include <fstream>
#include <string>
#include <iomanip>
#include <cmath>
using namespace std;

#include "pgm.h"
#define ALLOW_COMMENTS     

void writePGM(string filename, PGM &w)
{
	if (w.type != "P2" && w.type != "P5") throw string("writePGM:  error:  invalid type: "+w.type);
	if (w.type == "P5") 
	throw string("writePGM:  sorry.  cannot write out P5 PGMs yet.  please write this for me.");
 
	ofstream o(filename.c_str());
	if (!o) throw string("writePGM:  error:  cannot open file for writing: "+filename);
	o << w.type << " " << w.nc << " " << w.nr << " ";
	if (w.comments.size()>0) o << endl<<w.comments;
    if (w.comments[w.comments.size()-1] != '\n' && w.comments[w.comments.size()-1] != '\r') o <<endl;
	 
	o << static_cast<int>(w.mv)<<endl;
	
	int i=0;       // # of elements output on this line so far.
	for (int r=0;r<w.nr;r++)
	{
        for (int c=0;c<w.nc;c++)
        {
            o << setw(3) << static_cast<int>(w.pix[r*w.nc+c]);
            if (i%16==15) o << endl;
            else          o << ' ';
        }
        o << endl;
        i=0;
    }
}
        
//......................................:................................

void stretch(PGM &sf, PGM &sl, double in_min, double in_max, double out_min, double out_max,  
             bool do_logscale)      // note:  default value for do_logscale is given only in the prototype.  Not here.
{
    double pv;
    sl.type = sf.type;
	sl.comments = sf.comments;
	sl.nc = sf.nc;
	sl.nr = sf.nr;
	double maxout = out_min;       // keeps track of max output value.

	if (sf.nr == 0 || sf.nc == 0) return;

	if (!do_logscale)
	{
		for(int r=0;r<sf.nr;r++)
		{
			for(int c=0;c<sf.nc;c++)
			{
                int ix = r*sf.nc+c;
				pv = sf.pix[ix];
				if (pv < in_min)
					sl.pix[ix] = out_min;
				else if (pv <= in_max)
				{
					sl.pix[ix] = out_min + (pv-in_min)/(in_max - in_min)*(out_max-out_min);
				}

				else
					sl.pix[ix] = out_max;
			maxout = max(maxout, sl.pix[ix]);
			}
		}
	}
	else
	{
		double maxval, val;
		maxval = log(1+in_max-in_min);
		for(int r=0;r<sf.nr;r++)
		{
			for(int c=0;c<sf.nc;c++)
			{
                int ix = r*sf.nc+c;
                pv = sf.pix[ix];
				if (pv < in_min)
					sl.pix[ix] = out_min;
				else if (pv <= in_max)
				{
					val = log(1+ pv - in_min);
					sl.pix[ix] = out_min + (val/maxval)*(out_max-out_min);
				}

				else
					sl.pix[ix] = out_max;
				maxout = max(maxout, sl.pix[ix]);
			}
		}
	}
	
	sl.mv = static_cast<int>(maxout);
}

void processPGM(PGM r, PGM d, PGM f, PGM &final)
{
	final.type = r.type;
	final.comments = r.comments;
	final.nc = r.nc;
	final.nr = r.nr;
	final.mv = r.mv;
	final.pix = new double[r.nc*r.nr];
	
		cout << r.nc;
		
	for(int i=0;i<r.nc*r.nr;i++)
	{		
		final.pix[i] = (r.pix[i] - d.pix[i]);
			
	}	

}

void dividePGM(PGM &final, PGM f)
{
	
	cout << "Divideing..." << endl;
	for(int i=0;i<f.nc*f.nr;i++)
	{	final.pix[i] = (final.pix[i] / f.pix[i]);
		cout << final.pix[i] << " ";
	}
	delete [] final.pix;
}


double getMV(PGM &r)
{
	return r.mv;
}

#ifdef ALLOW_COMMENTS

void readPGM(string filename, PGM &v)
{
    bool got_nr = false, got_nc = false, got_maxval = false;
    string ty, cmnt;
    double val;
    int ival;
    char ch;
    v.pix = new double[v.nc*v.nr];
    //double pix[v.nc*v.nr];
   // v.pix = pix;

	ifstream s(filename.c_str(),  ios::in | ios::binary);  // you can still use >> on binary files.  it just doesn't translate newlines into newline/returns
	if (!s) throw string("readPGM:  error:  cannot open file " + filename);

	s >> ty;
	if (ty != "P2" && ty != "P5")
        throw string("readPGM:  error:  not a PGM: " + ty);

			// this rather awkward code is necessary to get around the possibility
			// of comments after the magic number and before the nr, nc & maxvals.
	while (!got_maxval)
	{
		ch = s.get();
		if (isspace(ch)) continue;
		else if (ch == '#')
		{
			getline(s, cmnt);
			v.comments += "#"+cmnt+'\n';
		}
		else 
		{	
			s.putback(ch);
			s >> val;
			if (!got_nc)
			{
				got_nc = true;
				v.nc = static_cast<int>(val);
				
			}
			else if (!got_nr)
			{
				got_nr = true;
				v.nr = static_cast<int>(val);
			}
			else if (!got_maxval)
			{
				v.mv = val;
				got_maxval = true;
			}
		}
		if (!s)
			throw string("readPGM:  error reading pgm header from "+filename);
	}

	s.get();	// skip over white space after maxval
	
	v.type = ty;
	if (v.type== "P5")
	{		
		s.read(reinterpret_cast<char*>(v.pix),sizeof(v.nc*v.nr));
		
		//if(!s)
       // throw string("readPGM:  P5 code dont work yet.  please write this code for me.");
	}
	else       // type is P2
	{
        for (int i=0;i<v.nc*v.nr;i++)
        {
            s >> ival;  // read in an integer value
            v.pix[i] = ival;  // save it in the pixel array, which is double.
        }
        
		if (!s)
			throw string("writePGM:  error reading array portion of pgm file.");
	}
	delete [] v.pix;
}

#endif

Please help me get this working!

[Ancient Dragon]

please describe the problem -- what does the program NOT do that it should? Are there any compiler errors? If yes, that are they. Runtime errors? What are they.

[Platanum]

Well, its hard to explain... I never get any compile errors, but then I run it once, and i get a runtime error (red text error warning), and the program terminates.

I run it again, without changing anything, and I may either get that same error, or it will go farther and give me that same error, OR, it will go even farther and give me a 'popup' error that the project needs to be terminated.

In anycase, it doesnt get very far, its getting hungup (at least as far as output goes) around the outputs in processPGM and dividePGM.

But I really dont know what the problem is...I'm still assuming something with memory allocation, deleteing...pointers structs, i just dont know!

[Ancient Dragon]

the PGM structure passed to readPGM is uninitialized -- all members contain random values. Yet readPGM is attempting to allocate an array of doubles based on these worthless values in nc and nr structure members.

v.pix = new double[v.nc*v.nr];