bmp.cpp

可以选择各种压缩方式对读入的图像进行压缩和解压

#include   "stdafx.h"
#include "bmp.h"
#include "release.h"

int loadBMP(char *filename, unsigned int &width, unsigned int &height, ptype ***Q){
	FILE *stream;
	ptype **P;
   // Open for read (will fail if file "crt_fopen.c" does not exist)
	if( fopen_s( &stream, filename, "rb" )  ) {
      printf( "The file %s was not opened\n",filename);
	  return 1;
	}
   else
      printf( "The file %s was opened\n" ,filename);

	//data offset
   fseek(stream,0xaL,SEEK_SET);
   unsigned int location;

   fread(&location,4,1,stream);

   //width&height
	fseek(stream,0x12L,SEEK_SET);
	fread(&width,4,1,stream);
	fread(&height,4,1,stream);

	//bitmap type
	fseek(stream,0x1cL,SEEK_SET);
	unsigned short bitw;
	fread(&bitw,2,1,stream);

	//initialize P
	P = new ptype *[height];
	if (!P) {
		printf("Allocate height error.\n");
		return 1;
	}
	for (unsigned int j=0; j<height; j++) {
		P[j]=new ptype [width];
		if (!P[j]) {
			printf("Allocate width error.\n");
			return 1;
		}
	}

	//bitmap data
	fseek(stream,long(location),SEEK_SET);

	for (unsigned int y=0; y<height; y++)
		fread(P[height-y-1],1,width,stream);

   // Close stream if it is not NULL 
   if( stream)
   {
      if ( fclose( stream ) )
      {
         printf( "The file '%s' was not closed\n",filename );
		 return 1;
      }
   }
   *Q=P;
   return 0;
}

void testLoadBMP()
{
	ptype ** P=NULL;
	unsigned int w,h;

	loadBMP("bmp1.bmp",w,h,&P);

	for (unsigned int i=0;i<h;i++){
		for (unsigned int j=0;j<w;j++)
			printf("%d\t",P[i][j]);
		printf("\n");
	}

	deleteP(P,h);
}