PIKApp/plug-ins/file-faxg3/g3.h

56 lines
1.3 KiB
C

/* #ident "@(#)g3.h 3.1 95/08/30 Copyright (c) Gert Doering" */
#ifndef NULL
#define NULL 0L
#endif
/* nr_bits is set to ( bit_length MOD FBITS ) by build_g3_tree,
* nr_pels is the number of pixels to write for that code,
* bit_code is the code itself (msb2lsb), and bit_length its length
*/
struct g3code { int nr_bits, nr_pels, bit_code, bit_length; };
/* tables for makeup / terminal codes white / black, extended m_codes */
extern struct g3code t_white[], m_white[], t_black[], m_black[], m_ext[];
/* The number of bits looked up simultaneously determines the amount
* of memory used by the program - some values:
* 10 bits : 87 Kbytes, 8 bits : 20 Kbytes
* 5 bits : 6 Kbytes, 1 bit : 4 Kbytes
* - naturally, using less bits is also slower...
*/
/*
#define FBITS 5
#define BITM 0x1f
*/
#define FBITS 8
#define BITM 0xff
/*
#define FBITS 12
#define BITM 0xfff
*/
#define BITN 1<<FBITS
struct g3_tree { int nr_bits;
struct g3_tree * nextb[ BITN ];
};
#define g3_leaf g3code
extern void tree_add_node ( struct g3_tree *p, struct g3code * g3c,
int bit_code, int bit_length );
extern void build_tree ( struct g3_tree ** p, struct g3code * c );
#ifdef DEBUG
extern void print_g3_tree ( char * t, struct g3_tree * p );
#endif
extern void init_byte_tab ( int reverse, int byte_tab[] );