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Typedefs | Enumerations | Functions | Variables
lzw.h File Reference

LZW decoding routines. More...

#include <stdint.h>

Go to the source code of this file.

Typedefs

typedef void LZWState
 

Enumerations

enum  FF_LZW_MODES { FF_LZW_GIF, FF_LZW_TIFF }
 

Functions

void ff_lzw_decode_open (LZWState **p)
 
void ff_lzw_decode_close (LZWState **p)
 
int ff_lzw_decode_init (LZWState *s, int csize, const uint8_t *buf, int buf_size, int mode)
 Initialize LZW decoder. More...
 
int ff_lzw_decode (LZWState *s, uint8_t *buf, int len)
 Decode given number of bytes NOTE: the algorithm here is inspired from the LZW GIF decoder written by Steven A. More...
 
int ff_lzw_decode_tail (LZWState *lzw)
 
void ff_lzw_encode_init (struct LZWEncodeState *s, uint8_t *outbuf, int outsize, int maxbits, enum FF_LZW_MODES mode, void(*lzw_put_bits)(struct PutBitContext *, int, unsigned int))
 
int ff_lzw_encode (struct LZWEncodeState *s, const uint8_t *inbuf, int insize)
 LZW main compress function. More...
 
int ff_lzw_encode_flush (struct LZWEncodeState *s, void(*lzw_flush_put_bits)(struct PutBitContext *))
 

Variables

const int ff_lzw_encode_state_size
 

Detailed Description

LZW decoding routines.

Author
Fabrice Bellard
modified for use in TIFF by Konstantin Shishkov

Definition in file lzw.h.

Typedef Documentation

typedef void LZWState

Definition at line 43 of file lzw.h.

Enumeration Type Documentation

Enumerator
FF_LZW_GIF 
FF_LZW_TIFF 

Definition at line 37 of file lzw.h.

Function Documentation

void ff_lzw_decode_open ( LZWState **  p)

Definition at line 113 of file lzw.c.

Referenced by gif_decode_init(), and tiff_init().

void ff_lzw_decode_close ( LZWState **  p)

Definition at line 118 of file lzw.c.

Referenced by gif_decode_close(), and tiff_end().

int ff_lzw_decode_init ( LZWState p,
int  csize,
const uint8_t buf,
int  buf_size,
int  mode 
)

Initialize LZW decoder.

Parameters
pLZW context
csizeinitial code size in bits
bufinput data
buf_sizeinput data size
modedecoder working mode - either GIF or TIFF

Definition at line 131 of file lzw.c.

Referenced by gif_read_image(), and tiff_unpack_strip().

int ff_lzw_decode ( LZWState p,
uint8_t buf,
int  len 
)

Decode given number of bytes NOTE: the algorithm here is inspired from the LZW GIF decoder written by Steven A.

Bennett in 1987.

Parameters
pLZW context
bufoutput buffer
lennumber of bytes to decode
Returns
number of bytes decoded

Definition at line 169 of file lzw.c.

Referenced by gif_read_image(), and tiff_unpack_strip().

int ff_lzw_decode_tail ( LZWState lzw)

Definition at line 99 of file lzw.c.

Referenced by gif_read_image().

void ff_lzw_encode_init ( struct LZWEncodeState s,
uint8_t outbuf,
int  outsize,
int  maxbits,
enum FF_LZW_MODES  mode,
void(*)(struct PutBitContext *, int, unsigned int lzw_put_bits 
)
int ff_lzw_encode ( LZWEncodeState s,
const uint8_t inbuf,
int  insize 
)

LZW main compress function.

Parameters
sLZW state
inbufInput buffer
insizeSize of input buffer
Returns
Number of bytes written or -1 on error

Definition at line 227 of file lzwenc.c.

Referenced by encode_strip(), and gif_image_write_image().

int ff_lzw_encode_flush ( struct LZWEncodeState s,
void(*)(struct PutBitContext *)  lzw_flush_put_bits 
)

Variable Documentation

const int ff_lzw_encode_state_size

Definition at line 67 of file lzwenc.c.

Referenced by encode_frame(), and gif_encode_init().