linu下C言語のBMP画像操作プログラミング(下)

#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>

#define  RGB(r,g,b)    		((r+g+b)/3)

typedef  unsigned char  U8 ; 
typedef  unsigned short U16 ; 
typedef  unsigned int   U32 ; 

#pragma  pack(1)
struct bmp_header
{
	//bmp header
	U8  Signatue[2] ;   // B  M
	U32 FileSize ;     //    
	U16 Reserv1 ; 
	U16 Reserv2 ; 
	U32 FileOffset ;   //      
	
	//DIB header
	U32 DIBHeaderSize ; //DIB   
	U32 ImageWidth   ;  //    
	U32 ImageHight   ;  //    
	U16 Planes       ; 
	U16 BPP          ;  //        
	U32 Compression  ; 
	U32 ImageSize    ;  //     
	U32 XPPM ; 
	U32 YPPM ; 
	U32 CCT ; 
	U32 ICC ;          
};
#pragma  pack()


int main(int argc , char **argv)
{
	if(argc != 4)
		return -1 ; 

	int fd ; 
	int dest_fd ; 
	fd = open(argv[1] , O_RDONLY);
	if(-1 == fd)
	{
		perror("open bmp file fail");
		return -2 ; 
	}

	dest_fd = open( argv[2] , O_RDWR | O_CREAT|O_TRUNC , 0777);
	if(dest_fd < 0 )
	{
		perror("open rgb565 fail");
		return -3 ; 
	}
	int value = atoi(argv[3]);

	struct bmp_header  header ; 

	int ret ; 
	
	ret = read(fd , &header , sizeof(struct bmp_header));


	printf(" Signatue[0]      : %c  
 " , header.Signatue[0]  );
	printf(" Signatue[1]      : %c  
 " , header.Signatue[1]  );
	printf(" FileSize         : %d  
 " , header.FileSize     );
	printf(" Reserv1          : %d  
 " , header.Reserv1      );
	printf(" Reserv2          : %d  
 " , header.Reserv2      );
	printf(" FileOffset       : %d  
 " , header.FileOffset   );
	printf(" DIBHeaderSize    : %d  
 " , header.DIBHeaderSize);
	printf(" ImageWidth       : %d  
 " , header.ImageWidth   );
	printf(" ImageHight       : %d  
 " , header.ImageHight   );
	printf(" Planes           : %d  
 " , header.Planes       );
	printf(" BPP              : %d  
 " , header.BPP          );
	printf(" Compression      : %d  
 " , header.Compression  );
	printf(" ImageSize        : %d  
 " , header.ImageSize    );
	printf(" XPPM             : %d  
 " , header.XPPM         );
	printf(" YPPM             : %d  
 " , header.YPPM         );
	printf(" CCT              : %d  
 " , header.CCT          );
	printf(" ICC              : %d  
 " , header.ICC          );

	char buffer[header.ImageSize] ; 

	read(fd , buffer , header.ImageSize);

	close(fd);

	//    

	write(dest_fd , &header , sizeof(struct bmp_header));

	int row , col ; 
	char *p = NULL ; 

	for(row = 0 ; row < 10 ; row++)
	{
		for(col = 0 ; col < 10 ; col++)
		{
			p = buffer + (row * 800 + col)*3 ; 
			*p = 255;
			*(p+1)=255;
			*(p+2)=255;	
		}
	}


	char data ; 
	for(row = 0 ; row < 480  ; row++)
	{
		for(col = 0 ; col < 800 ; col++)
		{
			p =( buffer+(row*800 + col)*3);
			data = RGB((unsigned char)(*(p+2)) , (unsigned char)(*(p+1)) , 
			(unsigned char )(*(p)));
			if(data < value)
			{
			*p = 0;
			*(p+1)=0;
			*(p+2)=0;	
			}
			else
			{
			*p = data;
			*(p+1)=data;
			*(p+2)=data;	
			}
			write(dest_fd , p , 3);
		}
	}

	close(dest_fd);

	return 0 ; 
}