netsurf/image/bmpread.h
Richard Wilson 6f654c6f1e [project @ 2006-02-28 00:45:15 by rjw]
Implement bitfield encoding for BMPs. We now correctly decode every image in the BMP test suite at http://pobox.com/~jason1/bmpsuite/

svn path=/import/netsurf/; revision=2099
2006-02-28 00:45:15 +00:00

74 lines
2.2 KiB
C

/*
* This file is part of NetSurf, http://netsurf.sourceforge.net/
* Licensed under the GNU General Public License,
* http://www.opensource.org/licenses/gpl-license
* Copyright 2006 Richard Wilson <info@tinct.net>
*/
/** \file
* BMP file decoding (interface).
*/
#ifndef _NETSURF_IMAGE_BMPREAD_H_
#define _NETSURF_IMAGE_BMPREAD_H_
#include <stdbool.h>
#include "netsurf/image/bitmap.h"
/* error return values */
typedef enum {
BMP_OK = 0,
BMP_INSUFFICIENT_MEMORY = 1,
BMP_INSUFFICIENT_DATA = 2,
BMP_DATA_ERROR = 3
} bmp_result;
/* encoding types */
typedef enum {
BMP_ENCODING_RGB = 0,
BMP_ENCODING_RLE8 = 1,
BMP_ENCODING_RLE4 = 2,
BMP_ENCODING_BITFIELDS = 3
} bmp_encoding;
struct bmp_image {
unsigned char *bmp_data; /** pointer to BMP data */
unsigned int buffer_size; /** total number of bytes of BMP data available */
unsigned int width; /** width of BMP (valid after _analyse) */
unsigned int height; /** heigth of BMP (valid after _analyse) */
bmp_encoding encoding; /** pixel encoding type */
unsigned int bitmap_offset; /** offset of bitmap data */
unsigned int bpp; /** bits per pixel */
unsigned int colours; /** number of colours */
unsigned int *colour_table; /** colour table */
bool reversed; /** scanlines are top to bottom */
bool decoded; /** whether the image has been decoded */
bool ico; /** image is part of an ICO, mask follows */
unsigned int mask[4]; /** four bitwise mask */
int shift[4]; /** four bitwise shifts */
struct bitmap *bitmap; /** decoded image */
};
struct ico_image {
struct bmp_image bmp;
struct ico_image *next;
};
struct ico_collection {
unsigned char *ico_data; /** pointer to ICO data */
unsigned int buffer_size; /** total number of bytes of ICO data available */
unsigned int width; /** width of largest BMP */
unsigned int height; /** heigth of largest BMP */
struct ico_image *first;
};
bmp_result bmp_analyse(struct bmp_image *bmp);
bmp_result bmp_decode(struct bmp_image *bmp);
void bmp_finalise(struct bmp_image *bmp);
bmp_result ico_analyse(struct ico_collection *ico);
struct bmp_image *ico_find(struct ico_collection *ico, int width, int height);
void ico_finalise(struct ico_collection *ico);
#endif