Thread: program to display an image in dos screen

i tried the following program given below to load and display a bmp file in a dos screen but it isn't working (image is not shown on screen) whats the problem???????

Code:

#include <dos.h>
#include <stdio.h>
#include <string.h>
#include <conio.h>
#include <windows.h>

 char far  *Screen;

/* Sets the display to VGA 320x200x256 */
 void VGAScreen(void)
  {
    union REGS r;

    r.h.ah = 0;
    r.h.al = 0x13;
    int86(0x10, &r, &r);
  return;
  }

/* Goes back to textmode */
void TextScreen(void)
{
  union  REGS r;

  r.h.ah = 0;
  r.h.al = 0x3;
  int86(0x10, &r, &r);

  return;
}

/* This sets a DAC register to a specific Red Green Blue-value */
int SetDAC(unsigned char DAC, unsigned char R, unsigned char G, unsigned char B)
{
  outportb(0x3C8, DAC);
  outportb(0x3C9, R);
  outportb(0x3C9, G);
  outportb(0x3C9, B);

  return(0);
}

int LoadBMP(void)
{
  struct BMPHeader
  {
    unsigned short  bfType;
    long            bfSize, bfReserved, bfOffBits, biSize, biWidth, biHeight;
    unsigned short  biPlanes, biBitCount;
    long            biCompression, biSizeImage, biXPelsPerMeter,
                    biYPelsPerMeter, biClrUsed, biClrImportant;
  } Header;

  FILE *BMPFile;
  unsigned char c, Palette[256][4];
  char          *filename = "rck.bmp";
  unsigned int  offset, lines, paddedWidth;

  /* This checks for the file */
  BMPFile = fopen(filename, "rb");

  if (BMPFile == NULL)
  {
    printf("Cant open file.");
    return(1);
  }

  /* Read the headerinformation */
  fread(&Header, 54, 1, BMPFile);

  if (Header.bfType != 19778 || Header.bfReserved != 0 || Header.biPlanes != 1)
  {
    /* Not a valid bitmap file - don't display */
    printf("Not a valid bitmap.");
    fclose(BMPFile);
    return(1);
  }

  if (Header.biCompression != 0)
  {
    /*Compressed file - don't display*/
    printf("Compressed file.");
    fclose(BMPFile);
    return(1);
  }

  if (Header.biBitCount != 8)
  {
    /*If the file is other than 8-bit dont read.*/
    printf("Not an 8-bit bitmap.");
    fclose(BMPFile);
    return(1);
  }

  if (Header.biWidth > 320 || Header.biHeight > 200)
  {
    /*If its larger than 320*200 dont load.*/
    printf("Size too large.");
    fclose(BMPFile);
    return(1);
  }

  /*Load the palette info*/
  fread(&Palette, 1024, 1, BMPFile);

  for (c = 0; c < 255; c++)
    SetDAC(c, Palette[c][2] >> 2, Palette[c][1] >> 2, Palette[c][0] >> 2);

  offset = (100 + (Header.biHeight >> 1)) * 320 + 160 - (Header.biWidth >> 1);
  lines = 0;
  paddedWidth = Header.biWidth & 0xFFFC;

  if (Header.biWidth != paddedWidth)
    paddedWidth += 4;

  /*Loop for reading lines*/
  while (lines < Header.biHeight)
  {
    fread(Screen + offset, paddedWidth, 1, BMPFile);
    offset -= 320;
    lines++;
  }

  fclose(BMPFile);
  return(0);
}

int main(int argcount, char *argvalue[])
{
  /* Set up a pointer in vga memory */
  Screen = (char far *) 0xA0000000L;
  VGAScreen();
  LoadBMP();
  getch();
  TextScreen();
  return(0);
}

image file was a 8 bit image file

thanks 4 ur reply.
my requirement is to load and display a 600*420 bmp file and program code has to be in c.
where can i get a sample code . can u help??????????

yes of course
if u can please guide me

i want to display a bmp file of resolution 600*420 (using c compiler)
by manual loading
i tried to display the image by loading the pixel value. but this method has a limitation that it take up pixel value of image upto 64kb size.
so now i am trying to load it manually.
what are the steps that i has to follow, what are the header files that i has to use ?
my system specification are windows xp professional , intel pentium 4 cpu.
i don't know where to start ,does this method has any limitaton ,...etc
somebody please help.

---

http://images.devshed.com/fds/buttons/edit.gif

i want to display a bmp file of resolution 600*420 (using c compiler)
by manual loading
i tried to display the image by loading the pixel value. but this method has a limitation that it take up pixel value of image upto 64kb size.
so now i am trying to load it manually.
what are the steps that i has to follow, what are the header files that i has to use ?
my system specification are windows xp professional , intel pentium 4 cpu.
i don't know where to start ,does this method has any limitaton ,...etc
compiler that i am using is turboc and codeblock
somebody please help.

O_o

This guy seems stuck in a loop.
This guy seems stuck in a loop.
This guy seems stuck in a loop.

Soma