gp_bmp.h File Reference

BMP image loader. More...

Go to the source code of this file.

Data Structures
struct	gp_bmp_info_header
	A BMP header. More...

Enumerations
enum	gp_bmp_compress {   COMPRESS_RGB = 0 , COMPRESS_RLE8 = 1 , COMPRESS_RLE4 = 2 , COMPRESS_BITFIELDS = 3 ,   COMPRESS_JPEG = 4 , COMPRESS_PNG = 5 , COMPRESS_ALPHABITFIELDS = 6 , COMPRESS_MAX = COMPRESS_ALPHABITFIELDS }
	BMP compression type. More...
enum	gp_bmp_info_header_size {   BITMAPCOREHEADER = 12 , BITMAPCOREHEADER2 = 64 , BITMAPINFOHEADER = 40 , BITMAPINFOHEADER2 = 52 ,   BITMAPINFOHEADER3 = 56 , BITMAPINFOHEADER4 = 108 , BITMAPINFOHEADER5 = 124 }
	BMP header size. More...

Functions
int	gp_bmp_read_info_header (gp_io *io, struct gp_bmp_info_header *header)
	Attempts to parse BMP info header at current offset in the file IO.
gp_pixel_type	gp_bmp_pixel_type (struct gp_bmp_info_header *header)
	Returns a pixel type suitable for a BMP info header.
uint32_t	gp_bmp_palette_size (struct gp_bmp_info_header *header)
	Returns palette size in bytes.
int	gp_bmp_read_pixels (gp_io *io, struct gp_bmp_info_header *header, gp_pixmap *pixmap, gp_progress_cb *callback)
	Reads a pixel data.

Detailed Description

BMP image loader.

Internal BMP loader functions, you shouldn't need to touch these unless you need to parse file formats that embedds a BMP images with incomplete header such as ICO file format.

Definition in file gp_bmp.h.

Enumeration Type Documentation

gp_bmp_compress

enum gp_bmp_compress

BMP compression type.

Enumerator
COMPRESS_RGB	Uncompressed.
COMPRESS_RLE8	Run-length encoded bitmap.
COMPRESS_RLE4	Run-length encoded bitmap.
COMPRESS_BITFIELDS	Bitfield for each channel.
COMPRESS_JPEG	Only for printers.
COMPRESS_PNG	Only for printers.
COMPRESS_ALPHABITFIELDS	Bitfields for each channel with alpha.
COMPRESS_MAX	Terminating entry.

Definition at line 65 of file gp_bmp.h.

gp_bmp_info_header_size

enum gp_bmp_info_header_size

BMP header size.

Enumerator
BITMAPCOREHEADER	Old OS/2 format + win 3.0.
BITMAPCOREHEADER2	OS/2.
BITMAPINFOHEADER	Most common.
BITMAPINFOHEADER2	Undocummented.
BITMAPINFOHEADER3	Undocummented.
BITMAPINFOHEADER4	Adds color space + gamma - win 95/NT4.
BITMAPINFOHEADER5	Adds ICC color profiles win 98+.

Definition at line 87 of file gp_bmp.h.

Function Documentation

gp_bmp_palette_size()

uint32_t gp_bmp_palette_size

(

struct gp_bmp_info_header *

header

)

Returns palette size in bytes.

Parameters

header

BMP info header structure.

Returns

Palette size in bytes.

gp_bmp_pixel_type()

gp_pixel_type gp_bmp_pixel_type

(

struct gp_bmp_info_header *

header

)

Returns a pixel type suitable for a BMP info header.

Returns a pixel type suitable for an pixmap that could be later passed to the gp_bmp_read_pixels().

Parameters

header

BMP info header.

Returns

A pixel type.

gp_bmp_read_info_header()

int gp_bmp_read_info_header	(	gp_io *	io,
		struct gp_bmp_info_header *	header )

Attempts to parse BMP info header at current offset in the file IO.

Note that pixel_offset is not set by this function since the offset to the pixels is stored in the bitmap file header. This offset must be filled in by the called before the header is passed to gp_bmp_read_pixels() function.

Parameters

io	An io stream with an BMP info header at current offset.
header	BMP info header to be filled in.

Returns

Zero on success and errno on a failure.

gp_bmp_read_pixels()

int gp_bmp_read_pixels	(	gp_io *	io,
		struct gp_bmp_info_header *	header,
		gp_pixmap *	pixmap,
		gp_progress_cb *	callback )

Reads a pixel data.

Parameters

io	An io stream.
header	BMP info header.
pixmap	Pre-allocated pixmap of correct size and pixel type.
callback	A progress callback.

Returns

Zero on success and errno on a failure.