Help me out plzzz

[biplab]

I have a minor problem with the following code..it reads a .bmp image
and is supposed to produce another .bmp image which is the result of
histogram equalization of the input image...kindly go through it
1st...and the query follows at the end...

#include <stdio.h>
#include <stdlib.h>
#include <dos.h>
#include <mem.h>
#include <string.h>
#include <conio.h>
#include <fcntl.h>
#include <io.h>
#include <math.h>

unsigned char r[360],mini,mode;
unsigned char rgb[256][3],rgb2[256][3],**rgb1;
char *fullname;
char *fname;
int hist[256],tmp=0,sum=0,t;
unsigned int screen_width=320;
unsigned int first_row=0,first_column=0,last_row=0,last_column=0;
int handle,i,j,rem,color_bits;
long int
file_size,data_offset,size_info_header,width,height,compression,

image_size,xpelspermeter,ypelspermeter,colorsused,k,colorsimpt,p,index,max,min,**sum_hist;
float theta,temp;
void drawdot(int x, int y, int pal_index){
_AX=pal_index;
_CX=x;
_DX=y;
_AH=0x0c;
_BH=0x00;
geninterrupt(0x10);
}

void main(){

gets(fname);
strcpy(fullname,fname);strcat(fullname,".bmp");
handle=_open(fullname,O_RDONLY);if (handle==-1) exit(EXIT_FAILURE);
_read(handle,r,2);if (r[0] !='B' | r[1] !='M') exit(EXIT_FAILURE);
_read(handle,r,
4);file_size=r[0]+0x100*r[1]+0x10000*r[2]+0x1000000*r[3];
_read(handle,r,2);_read(handle,r,2);
_read(handle,r,
4);data_offset=r[0]+256*r[1]+65536*r[2]+0x1000000*r[3];
_read(handle,r,
4);size_info_header=r[0]+256*r[1]+65536*r[2]+0x1000000*r[3];
if (size_info_header !=40) exit(EXIT_FAILURE);
_read(handle,r,4);width=r[0]+0x100*r[1]+0x10000*r[2]+0x1000000*r[3];
if (width > screen_width) exit(0);
_read(handle,r,4);height=r[0]+0x100*r[1]+0x10000*r[2]+0x1000000*r[3];
_read(handle,r,2);if (r[0] != 1) exit(EXIT_FAILURE);
_read(handle,r,2);
color_bits=r[0];
_read(handle,r,4);
compression=r[0]+0x100*r[1]+0x10000*r[2]+0x1000000*r[3];
_read(handle,r,4);
image_size=r[0]+256*r[1]+256*256*r[2]+256*256*256*r[3];
_read(handle,r,4);
xpelspermeter=r[0]+0x100*r[1]+0x10000*r[2]+0x1000000*r[3];
_read(handle,r,4);
ypelspermeter=r[0]+0x100*r[1]+0x10000*r[2]+0x1000000*r[3];
_read(handle,r,4);
colorsused=r[0]+0x100*r[1]+0x10000*r[2]+0x1000000*r[3];
_read(handle,r,4);
colorsimpt=r[0]+0x100*r[1]+0x10000*r[2]+0x1000000*r[3];

_AX=0x1201;_BL=0x33;geninterrupt(0x10);//don't add RGB
_AX=0x0013;geninterrupt(0x10);//set mode 13 i.e. 320x200x256

for (i=0;i<256;i++) {
_read(handle,r,4);
rgb[0]=r[2]>>2;rgb[1]=r[1]>>2;rgb[2]=r[0]>>2;
}
rgb1=calloc(height,sizeof(char*));
for(i=0;i<height;i++)
rgb1=calloc(width,sizeof(char));
for (i=0;i<256;i++) {
rgb2[0]=i;rgb2[1]=i;rgb2[2]=i;
}
_ES=FP_SEG(rgb2);_DX=FP_OFF(rgb2);
_BX=0;_CX=0x100; _AX=0x1012;
geninterrupt(0x10);//set DAC from rgb

first_column=(screen_width-width)/2;
last_row=first_row+height-1;last_column=first_column+width-1;
rem=4 - (width % 4);
for (i=0;i<=height-1;i++) {
_read(handle,r,width);

for (j=0;j<=width-1;j++)
{
//drawdot(first_column+j,last_row-i,r[j]);
rgb1[j]=(rgb2[r[j]][0]+rgb2[r[j]][1]+rgb2[r[j]][2])/3;

}
if (rem==1) _read(handle,r,1);
else if (rem==2) _read(handle,r,2);
else if (rem==3) _read(handle,r,3);//getch();
}

for(i=0;i<256;i++)
{
hist=0;
}
for(i=0;i<height;i++)
{
for(j=0;j<width;j++)
{
k=(long int)rgb1[j];
hist[k]=hist[k]+1;
}
}

for(i=0;i<256;i++)
{
if(hist!=0)
tmp++;
else continue;
}

sum_hist=(long int **)calloc(tmp,sizeof(long int*));
for(i=0;i<tmp;i++)
sum_hist=(long int *)calloc(2,sizeof(long int));
for(i=0;i<256;i++)
{
if(hist!=0)
{
sum_hist[sum][0]=(long int)i;
sum_hist[sum][1]=(long int)hist;
sum++;
}
else continue;
}


for(i=1;i<tmp;i++)
sum_hist[1]+=sum_hist[i-1][1];


min=sum_hist[0][1];
max=sum_hist[0][1];
for(i=1;i<tmp;i++)
{
if(min>sum_hist[1])
min=sum_hist[1];
else continue;
}
for(i=1;i<tmp;i++)
{
if(max<sum_hist[1])
max=sum_hist[1];
else continue;
}

p=((height*width)-min);

for(i=0;i<height;i++)
{
for(j=0;j<widthj++)
{
t=(int)rgb1[j];
for(i=0;i<tmp;i++)
{
if(sum_hist[0]==t)
index=sum_hist[1];
}
index=index-min;
rgb1[j]=abs(index*255/p);
//drawdot(first_column+j,last_row-i,rgb1[j]);
}
}
/*for(i=0;i<height;i++)
{
for(j=0;j<width;j++)
drawdot(first_column+j,last_row-i,rgb1[j]);
}*/

_close(handle);
getch();
_AX=0x1201;_BL=0x33;geninterrupt(0x10);//don't add RGB
_AX=0x0003;geninterrupt(0x10);//set mode 3 i.e. 16-color text

}

tillthis following segment..
for(i=0;i<height;i++)
{
for(j=0;j<widthj++)
{
t=(int)rgb1[j];
for(i=0;i<tmp;i++)
{
if(sum_hist[0]==t)
index=sum_hist[1];
}
index=index-min;
rgb1[j]=abs(index*255/p);
//drawdot(first_column+j,last_row-i,rgb1[j]);
}
everything is going well...but nothing is being done as soon as the
for loops end...therefore I cant print the output image..What is the
remedy???

 

[Ben Bacarisse]

I have a minor problem with the following code..it reads a .bmp image
and is supposed to produce another .bmp image which is the result of
histogram equalization of the input image...kindly go through it
1st...and the query follows at the end...

char *fname;

void main(){

gets(fname);

This looks familiar. Did you not understand the advice you got last
time? Use int main(void), don't use gets, and ensure that when you
read in data there is somewhere for it to go (fname is NULL). There
were other comments but, I'd start here if I were you.

 

[Barry Schwarz]

I have a minor problem with the following code..it reads a .bmp image
and is supposed to produce another .bmp image which is the result of
histogram equalization of the input image...kindly go through it
1st...and the query follows at the end...

This code has all the same problems as the similar code you posted on
10 September in the "Reading .bmp file in C" thread. Until you apply
the corrections suggested in that thread there is no point in
repeating them here.