lzw.c File Reference

LZW decoding routines. More...

#include "avcodec.h"
#include "bytestream.h"
#include "lzw.h"
#include "libavutil/mem.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)
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 35 of file lzw.c.

Referenced by ff_lzw_decode(), and ff_lzw_decode_init().

#define LZW_SIZTABLE   (1<<LZW_MAXBITS)

Definition at line 36 of file lzw.c.

Function Documentation

static int lzw_get_code ( struct LZWState *  s )

static

Definition at line 70 of file lzw.c.

Referenced by ff_lzw_decode().

void ff_lzw_decode_tail

(

LZWState *

p

)

Definition at line 96 of file lzw.c.

Referenced by gif_read_image().

av_cold void ff_lzw_decode_open

(

LZWState **

p

)

Definition at line 109 of file lzw.c.

Referenced by gif_decode_init(), and tiff_init().

av_cold void ff_lzw_decode_close

(

LZWState **

p

)

Definition at line 114 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

p	LZW context
csize	initial code size in bits
buf	input data
buf_size	input data size
mode	decoder working mode - either GIF or TIFF

Definition at line 127 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

p	LZW context
buf	output buffer
len	number of bytes to decode

Returns

number of bytes decoded

Definition at line 165 of file lzw.c.

Referenced by gif_read_image(), and tiff_unpack_strip().

Variable Documentation

const uint16_t mask[17]

static

Initial value:

=
{
    0x0000, 0x0001, 0x0003, 0x0007,
    0x000F, 0x001F, 0x003F, 0x007F,
    0x00FF, 0x01FF, 0x03FF, 0x07FF,
    0x0FFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF
}

Definition at line 38 of file lzw.c.

Referenced by ac3_lshift_int16_c(), add_hfyu_left_prediction_int16_c(), add_int16_c(), av_read_image_line(), av_set_cpu_flags_mask(), binkb_read_bundle(), build_xlaw_table(), cinepak_decode_codebook(), cinepak_decode_vectors(), cmp_direct_inline(), dca_decode_frame(), dca_parse_audio_coding_header(), dca_xxch2index(), decode_0(), decode_13(), decode_bmv_frame(), decode_channel_code_tab(), decode_clnpass(), decode_dds1(), decode_dsw1(), decode_init(), decode_mvc1(), decode_mvc2(), decode_qu_spectra(), decode_residual(), decode_residual_block(), decode_sigpass(), decode_tsw1(), decodeplane32(), diff_int16_c(), diff_pixels_mvi(), drawtext(), encode_alpha_plane(), encode_clnpass(), encode_codeword(), encode_plane_bitstream(), encode_refpass(), encode_sigpass(), escape124_decode_frame(), est_alpha_diff(), estimate_alpha_plane(), ff_acelp_fc_pulse_per_track(), ff_blend_mask(), ff_decode_10_pulses_35bits(), ff_draw_pc_font(), ff_er_add_slice(), ff_h264_check_intra4x4_pred_mode(), ff_lsb2full(), ff_lzw_decode(), ff_lzw_decode_init(), ff_vector_fmul_add_altivec(), filter_channel(), get_cabac_bypass_sign(), get_len(), get_mb_score(), init(), init_cavlc_level_tab(), init_luts(), ljpeg_decode_rgb_scan(), ljpeg_decode_yuv_scan(), mp3_write_xing(), mpc8_decode_frame(), mpc8_get_mask(), mszh_decomp(), pack_int32(), picmemset(), png_get_interlaced_row(), png_put_interlaced_row(), pp_get_mode_by_name_and_quality(), pred_mv(), pred_spatial_direct_motion(), process_float(), put_alpha_diff(), put_subframe_samples(), put_swf_line_edge(), put_swf_rect(), read_residue(), rematrix_channels(), run_opencl_bench(), rv34_decode_cbp(), rv34_pred_mv_b(), subsampling_bounds(), ulti_pattern(), unpack_alpha(), vertClassify_altivec(), vp56_mc(), vp6_filter(), write_element(), x8_get_ac_rlf(), and xan_unpack_luma().