converting a color iage to grayscale

#include<stdio.h>
#include<string.h>
#include<conio.h>
#include<stdlib.h>
#include<iostream.h>
#include<math.h>
#include<fstream.h>


#define MAXX 300
#define MAXY 300

#define biwidth 256
#define biheight 256
#define off_bits 1078


struct bithead    //Defining header structure.
	{
	char bm[2];
	long int size;
	int no1;
	int no2;
	long int offset;
	};

struct info_header  //Defining info header structure
	{
	long int size1;
	long int width;
	long int height;
	int plane;
	int bit_count;
	long int comp;
	long int simage;
	long int xppm;
	long int yppm;
	long int clrused;
	long int clrimp;
	};
//function prototype
void write_to_file(FILE *);
void read_image_into_array(FILE *);
void make_image_data_binary();             // 0 or 1

//Global variables declaration
int huge image[MAXX][MAXY];
char a[1078];

// ---------------Main program begins---------------------------
void main()
  {
	clrscr();
	FILE *fp,*op;
	struct bithead bmp;      //Structure Variable is defined file header.
	struct info_header inf;  //Structure Variable is defined for image info header.


	fp=fopen("bird.bmp","rb"); //source BMP File is Opened in read binary mode

	if(fp==NULL)               //On failure in file open, program terminates.
				  {
	  cout<<"Cannot open the file";
		  getch();
		  exit(0);
	  }

	fread(&bmp,sizeof(bmp),1,fp);         //Reading header
	fread(&inf,sizeof(inf),1,fp); 	       //reading file info header

	//Displaying the BMP File Header.
	cout<<"\n********Header information*********\n\n";
	cout<<"\nBMP FILE HEADER="<<bmp.bm;
	cout<<"\n\nSize of file="<<bmp.size;
	cout<<"\nRESERVED WORD1="<<bmp.no1;
	cout<<"\nRESERVED WORD2="<<bmp.no2;
	cout<<"\nOffset of Data="<<bmp.offset;

	 //Displaying the BMP IMG INFO Header.

	cout<<"\n\nBITMAP INFO HEADER";
	cout<<"\n\nSize of Bitmap Info header="<<inf.size1;
	cout<<"\nWidth of Bitmap="<<inf.width;
	cout<<"\nHeight of Bitmap="<<inf.height;
	cout<<"\nNumber of planes="<<inf.plane;
	cout<<"\nNumber of bits per pixel="<<inf.bit_count;
	cout<<"\nType of Compression="<<inf.comp;
	cout<<"\nSize of image="<<inf.simage;
	cout<<"\nHorizontal Resolution="<<inf.xppm;
	cout<<"\nVertical Resolution="<<inf.yppm;
	cout<<"\nNo. of Colors used="<<inf.clrused;
	cout<<"\nNo. of Important Colors ="<<inf.clrimp;

	fclose(fp);


	fp=fopen("bird.bmp","rb");
	op=fopen("c:\\tc\\results\\copy.bmp","wb");

	printf("\n********************************** \n");
	printf("\nImage Copied at following location: \n");
	printf("\nc:\\tc\\results \n");


  if(fp==NULL||op==NULL)
   {

   exit(0);
   }

   fread(&a,sizeof(a),1,fp);    //bird.bmp
   fwrite(&a,sizeof(a),1,op);   //copy.bmp

   read_image_into_array(fp);
   fclose(fp);
	write_to_file(op);
	fclose(op);
//------------------------------------------------


   fp=fopen("bird.bmp","rb");

   if(fp==NULL)
   {

   exit(0);
   }

   fread(&a,sizeof(a),1,fp);


   read_image_into_array(fp);
   fclose(fp);


  op=fopen("c:\\tc\\results\\binary.bmp","wb"); //binary.bmp
  fwrite(&a,sizeof(a),1,op);

printf("\n********************************** \n");
printf("\nImage Binarization successfully performed \n");
printf("\Binary Image stored at following location: \n");
printf("\nc:\\tc\\results \n");


	make_image_data_binary();

	write_to_file(op);
	fclose(op);
	printf("\n********************************** \n");

	getch();
	exit(0);
}

void write_to_file(FILE *file)
{
	int x=0,y=0;
	fseek(file,off_bits,0);
	for(x=0;x<biheight;x++)>
		for(y=0;y<biwidth;y++)>
			fputc(int(image[x][y]),file);
}

/* function : read_image_into_array
   input    : Input image file .bmp format
   output   : 2D Array containing intensity values of each pixel in the image
*/


void read_image_into_array(FILE *file)
{
	int x=0,y=0;
	fseek(file,off_bits,0);
	for(x=0;x<biheight;x++)>
		for(y=0;y<biwidth;y++)>
			image[x][y]=fgetc(file);

}

void make_image_data_binary()
{
	int x=0,y=0;
	for(x=0;x<biheight;x++)>
		for(y=0;y<biwidth;y++)>
		{
			if(image[x][y]>128)
				image[x][y]=255;
			else if(image[x][y]<=128)
				image[x][y]=0;
		}
}