libbmp.h

#ifndef __LIBBMP_H__
#define __LIBBMP_H__

#define BMP_MAGIC 19778

#define BMP_GET_PADDING(a) ((a) % 4)

enum bmp_error
{
	BMP_FILE_NOT_OPENED = -4,
	BMP_HEADER_NOT_INITIALIZED,
	BMP_INVALID_FILE,
	BMP_ERROR,
	BMP_OK = 0
};

typedef struct _bmp_header
{
	unsigned int   bfSize;
	unsigned int   bfReserved;
	unsigned int   bfOffBits;
	
	unsigned int   biSize;
	int            biWidth;
	int            biHeight;
	unsigned short biPlanes;
	unsigned short biBitCount;
	unsigned int   biCompression;
	unsigned int   biSizeImage;
	int            biXPelsPerMeter;
	int            biYPelsPerMeter;
	unsigned int   biClrUsed;
	unsigned int   biClrImportant;
} bmp_header;

typedef struct _bmp_pixel
{
	unsigned char blue;
	unsigned char green;
	unsigned char red;
} bmp_pixel;

// This is faster than a function call
#define BMP_PIXEL(r,g,b) ((bmp_pixel){(b),(g),(r)})

typedef struct _bmp_img
{
	bmp_header   img_header;
	bmp_pixel  **img_pixels;
} bmp_img;

// BMP_HEADER
void            bmp_header_init_df             (bmp_header*,
                                                const int,
                                                const int);

enum bmp_error  bmp_header_write               (const bmp_header*,
                                                FILE*);

enum bmp_error  bmp_header_read                (bmp_header*,
                                                FILE*);

// BMP_PIXEL
void            bmp_pixel_init                 (bmp_pixel*,
                                                const unsigned char,
                                                const unsigned char,
                                                const unsigned char);

// BMP_IMG
void            bmp_img_alloc                  (bmp_img*);
void            bmp_img_init_df                (bmp_img*,
                                                const int,
                                                const int);
void            bmp_img_free                   (bmp_img*);

enum bmp_error  bmp_img_write                  (const bmp_img*,
                                                const char*);

enum bmp_error  bmp_img_read                   (bmp_img*,
                                                const char*);

#endif /* __LIBBMP_H__ */