6-1.c

《C语言程序设计实训》第六章

/*6-1.c*/
#include "conio.h"
#include "stdio.h"
#include "dos.h"
#include "stdlib.h"
#define lengthlimit 640
#define   highlimit 480
int Set640_480 (void)
{
 asm  mov ax,4f02h
 asm  mov bx,0101h
 asm  int 10h
 if((_AL==0x4f)&&(_AH==0))
 {
    return(0);
 }
 return(1);
}
void Set_Page(int page)
{
 asm mov ax,4f05h
 asm mov bx,0
 asm mov dx,page
 asm int 10h
}
void myputpixel (int row,int col,unsigned char color)
/*(row,col)画点的坐标，color画点颜色*/
{
 unsigned long dantance;
 unsigned y;
 static int totalpage=0;
 int page;
 dantance=1l*col*lengthlimit+row;
 y=(unsigned)(dantance&0X0000ffffl);
 page=(int)(1.0*dantance/65536);
 if (totalpage!=page) {  totalpage=page;  Set_Page(page);  }
 asm {
       mov ax,0a000h
       mov es,ax
       mov si,y
       mov al,color
       mov es:[si],al
     }
}
void bmpout(char *bmpstr)
/* 打开文件名为*bmpstr的BMP文件，输出图象*/
{
 FILE *bmpfp;
 struct bmp{
	     int bftype;
	     long bfsize;
	     long bfr;
	     long bfoff;
	     long bisize;
	     long biwidth ;
	     long biheight;
	   } bmpp;
 struct DAC{
	    char blue;
	    char green;
	    char red;
	   };
 struct DAC dacp[256];
 char pp;
 int colorcount,x,y,i,j,x0=0,y0=470,k,bibit,svg;
 char resev,buf1 ;
 void  *buf;
 Set640_480();
 if((bmpfp=fopen(bmpstr,"rb"))==NULL)
  {
  printf("can't open file");
  return;
 }
 fread(&bmpp,sizeof(bmpp),1,bmpfp);
 fseek(bmpfp,28l,SEEK_SET);
 fread(&bibit,2,1,bmpfp);
 fseek(bmpfp,46l,SEEK_SET);
 fread(&colorcount,sizeof(colorcount),1,bmpfp);
 if (colorcount==0) { colorcount=256;}
 fseek (bmpfp,54l,SEEK_SET);
 for (i=0;i<colorcount;i++)
  {
   fread(&dacp[i],3,1,bmpfp);
   fread(&resev,1,1,bmpfp);
  }
 for(i=0;i<colorcount;i++)
 {
   pp=dacp[i].red>>2;
   dacp[i].red=dacp[i].blue>>2;
   dacp[i].blue=pp;
   dacp[i].green=(dacp[i].green>>2);
 }
  asm push es
 _ES=FP_SEG(dacp);
 _DX=FP_OFF (dacp);
  asm mov bx,0
  asm mov cx,colorcount
  asm mov ah,10h
  asm mov al,12h
  asm int 10h
  asm pop es
  fseek(bmpfp,bmpp.bfoff,SEEK_SET);
  buf=malloc(bmpp.biwidth);
  for(i=0;i<bmpp.biheight;i++)
  {
    y=y0-i;
    fread(buf,bmpp.biwidth,1,bmpfp);
    for( j=x0;j<x0+bmpp.biwidth;j++)
     myputpixel(j,y,*((unsigned char*)buf+j));
   }
 free(buf);
 getch();
 fclose(bmpfp);
 delay(500);
 return;
}
void main()
{
bmpout("*.bmp");  /* 打开某一BMP文件并输出图象*/
}