lzw.c File Reference

LZW decoding routines. More...

#include "avcodec.h"
#include "lzw.h"

Go to the source code of this file.

Data Structures

struct  LZWState

Macros

#define LZW_MAXBITS   12
#define LZW_SIZTABLE   (1<<LZW_MAXBITS)

Functions

static int lzw_get_code (struct LZWState *s)
const uint8_t * ff_lzw_cur_ptr (LZWState *p)
void ff_lzw_decode_tail (LZWState *p)
av_cold void ff_lzw_decode_open (LZWState **p)
av_cold void ff_lzw_decode_close (LZWState **p)
int ff_lzw_decode_init (LZWState *p, int csize, const uint8_t *buf, int buf_size, int mode)
 Initialize LZW decoder.
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.

Variables

static const uint16_t mask [17]

Detailed Description

LZW decoding routines.

Author
Fabrice Bellard
modified for use in TIFF by Konstantin Shishkov

Definition in file lzw.c.

Macro Definition Documentation

#define LZW_MAXBITS   12

Definition at line 33 of file lzw.c.

Referenced by ff_lzw_decode(), and ff_lzw_decode_init().

#define LZW_SIZTABLE   (1<<LZW_MAXBITS)

Definition at line 34 of file lzw.c.

Function Documentation

const uint8_t* ff_lzw_cur_ptr ( LZWState p)

Definition at line 94 of file lzw.c.

Referenced by gif_read_image().

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 174 of file lzw.c.

Referenced by gif_read_image(), and tiff_unpack_strip().

av_cold void ff_lzw_decode_close ( LZWState **  p)

Definition at line 122 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 135 of file lzw.c.

Referenced by gif_read_image(), and tiff_unpack_strip().

av_cold void ff_lzw_decode_open ( LZWState **  p)

Definition at line 117 of file lzw.c.

Referenced by gif_decode_init(), and tiff_init().

void ff_lzw_decode_tail ( LZWState p)

Definition at line 99 of file lzw.c.

Referenced by gif_read_image().

static int lzw_get_code ( struct LZWState s)
static

Definition at line 68 of file lzw.c.

Referenced by ff_lzw_decode().

Variable Documentation