+++ /dev/null
-/* deflate.h -- internal compression state
- * Copyright (C) 1995-2004 Jean-loup Gailly
- * For conditions of distribution and use, see copyright notice in zlib.h
- */
-
-/* WARNING: this file should *not* be used by applications. It is
- part of the implementation of the compression library and is
- subject to change. Applications should only use zlib.h.
- */
-
-/* @(#) $Id: deflate.h,v 1.2 2008/05/26 19:08:10 vp153 Exp $ */
-
-#ifndef DEFLATE_H
-#define DEFLATE_H
-
-#include "zutil.h"
-
-/* define NO_GZIP when compiling if you want to disable gzip header and
- trailer creation by deflate(). NO_GZIP would be used to avoid linking in
- the crc code when it is not needed. For shared libraries, gzip encoding
- should be left enabled. */
-#ifndef NO_GZIP
-# define GZIP
-#endif
-
-/* ===========================================================================
- * Internal compression state.
- */
-
-#define LENGTH_CODES 29
-/* number of length codes, not counting the special END_BLOCK code */
-
-#define LITERALS 256
-/* number of literal bytes 0..255 */
-
-#define L_CODES (LITERALS+1+LENGTH_CODES)
-/* number of Literal or Length codes, including the END_BLOCK code */
-
-#define D_CODES 30
-/* number of distance codes */
-
-#define BL_CODES 19
-/* number of codes used to transfer the bit lengths */
-
-#define HEAP_SIZE (2*L_CODES+1)
-/* maximum heap size */
-
-#define MAX_BITS 15
-/* All codes must not exceed MAX_BITS bits */
-
-#define INIT_STATE 42
-#define EXTRA_STATE 69
-#define NAME_STATE 73
-#define COMMENT_STATE 91
-#define HCRC_STATE 103
-#define BUSY_STATE 113
-#define FINISH_STATE 666
-/* Stream status */
-
-
-/* Data structure describing a single value and its code string. */
-typedef struct ct_data_s {
- union {
- ush freq; /* frequency count */
- ush code; /* bit string */
- } fc;
- union {
- ush dad; /* father node in Huffman tree */
- ush len; /* length of bit string */
- } dl;
-} FAR ct_data;
-
-#define Freq fc.freq
-#define Code fc.code
-#define Dad dl.dad
-#define Len dl.len
-
-typedef struct static_tree_desc_s static_tree_desc;
-
-typedef struct tree_desc_s {
- ct_data *dyn_tree; /* the dynamic tree */
- int max_code; /* largest code with non zero frequency */
- static_tree_desc *stat_desc; /* the corresponding static tree */
-} FAR tree_desc;
-
-typedef ush Pos;
-typedef Pos FAR Posf;
-typedef unsigned IPos;
-
-/* A Pos is an index in the character window. We use short instead of int to
- * save space in the various tables. IPos is used only for parameter passing.
- */
-
-typedef struct internal_state {
- z_streamp strm; /* pointer back to this zlib stream */
- int status; /* as the name implies */
- Bytef *pending_buf; /* output still pending */
- ulg pending_buf_size; /* size of pending_buf */
- Bytef *pending_out; /* next pending byte to output to the stream */
- uInt pending; /* nb of bytes in the pending buffer */
- int wrap; /* bit 0 true for zlib, bit 1 true for gzip */
- gz_headerp gzhead; /* gzip header information to write */
- uInt gzindex; /* where in extra, name, or comment */
- Byte method; /* STORED (for zip only) or DEFLATED */
- int last_flush; /* value of flush param for previous deflate call */
-
- /* used by deflate.c: */
-
- uInt w_size; /* LZ77 window size (32K by default) */
- uInt w_bits; /* log2(w_size) (8..16) */
- uInt w_mask; /* w_size - 1 */
-
- Bytef *window;
- /* Sliding window. Input bytes are read into the second half of the window,
- * and move to the first half later to keep a dictionary of at least wSize
- * bytes. With this organization, matches are limited to a distance of
- * wSize-MAX_MATCH bytes, but this ensures that IO is always
- * performed with a length multiple of the block size. Also, it limits
- * the window size to 64K, which is quite useful on MSDOS.
- * To do: use the user input buffer as sliding window.
- */
-
- ulg window_size;
- /* Actual size of window: 2*wSize, except when the user input buffer
- * is directly used as sliding window.
- */
-
- Posf *prev;
- /* Link to older string with same hash index. To limit the size of this
- * array to 64K, this link is maintained only for the last 32K strings.
- * An index in this array is thus a window index modulo 32K.
- */
-
- Posf *head; /* Heads of the hash chains or NIL. */
-
- uInt ins_h; /* hash index of string to be inserted */
- uInt hash_size; /* number of elements in hash table */
- uInt hash_bits; /* log2(hash_size) */
- uInt hash_mask; /* hash_size-1 */
-
- uInt hash_shift;
- /* Number of bits by which ins_h must be shifted at each input
- * step. It must be such that after MIN_MATCH steps, the oldest
- * byte no longer takes part in the hash key, that is:
- * hash_shift * MIN_MATCH >= hash_bits
- */
-
- long block_start;
- /* Window position at the beginning of the current output block. Gets
- * negative when the window is moved backwards.
- */
-
- uInt match_length; /* length of best match */
- IPos prev_match; /* previous match */
- int match_available; /* set if previous match exists */
- uInt strstart; /* start of string to insert */
- uInt match_start; /* start of matching string */
- uInt lookahead; /* number of valid bytes ahead in window */
-
- uInt prev_length;
- /* Length of the best match at previous step. Matches not greater than this
- * are discarded. This is used in the lazy match evaluation.
- */
-
- uInt max_chain_length;
- /* To speed up deflation, hash chains are never searched beyond this
- * length. A higher limit improves compression ratio but degrades the
- * speed.
- */
-
- uInt max_lazy_match;
- /* Attempt to find a better match only when the current match is strictly
- * smaller than this value. This mechanism is used only for compression
- * levels >= 4.
- */
-# define max_insert_length max_lazy_match
- /* Insert new strings in the hash table only if the match length is not
- * greater than this length. This saves time but degrades compression.
- * max_insert_length is used only for compression levels <= 3.
- */
-
- int level; /* compression level (1..9) */
- int strategy; /* favor or force Huffman coding*/
-
- uInt good_match;
- /* Use a faster search when the previous match is longer than this */
-
- int nice_match; /* Stop searching when current match exceeds this */
-
- /* used by trees.c: */
- /* Didn't use ct_data typedef below to supress compiler warning */
- struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
- struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
- struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
-
- struct tree_desc_s l_desc; /* desc. for literal tree */
- struct tree_desc_s d_desc; /* desc. for distance tree */
- struct tree_desc_s bl_desc; /* desc. for bit length tree */
-
- ush bl_count[MAX_BITS+1];
- /* number of codes at each bit length for an optimal tree */
-
- int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
- int heap_len; /* number of elements in the heap */
- int heap_max; /* element of largest frequency */
- /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
- * The same heap array is used to build all trees.
- */
-
- uch depth[2*L_CODES+1];
- /* Depth of each subtree used as tie breaker for trees of equal frequency
- */
-
- uchf *l_buf; /* buffer for literals or lengths */
-
- uInt lit_bufsize;
- /* Size of match buffer for literals/lengths. There are 4 reasons for
- * limiting lit_bufsize to 64K:
- * - frequencies can be kept in 16 bit counters
- * - if compression is not successful for the first block, all input
- * data is still in the window so we can still emit a stored block even
- * when input comes from standard input. (This can also be done for
- * all blocks if lit_bufsize is not greater than 32K.)
- * - if compression is not successful for a file smaller than 64K, we can
- * even emit a stored file instead of a stored block (saving 5 bytes).
- * This is applicable only for zip (not gzip or zlib).
- * - creating new Huffman trees less frequently may not provide fast
- * adaptation to changes in the input data statistics. (Take for
- * example a binary file with poorly compressible code followed by
- * a highly compressible string table.) Smaller buffer sizes give
- * fast adaptation but have of course the overhead of transmitting
- * trees more frequently.
- * - I can't count above 4
- */
-
- uInt last_lit; /* running index in l_buf */
-
- ushf *d_buf;
- /* Buffer for distances. To simplify the code, d_buf and l_buf have
- * the same number of elements. To use different lengths, an extra flag
- * array would be necessary.
- */
-
- ulg opt_len; /* bit length of current block with optimal trees */
- ulg static_len; /* bit length of current block with static trees */
- uInt matches; /* number of string matches in current block */
- int last_eob_len; /* bit length of EOB code for last block */
-
-#ifdef DEBUG
- ulg compressed_len; /* total bit length of compressed file mod 2^32 */
- ulg bits_sent; /* bit length of compressed data sent mod 2^32 */
-#endif
-
- ush bi_buf;
- /* Output buffer. bits are inserted starting at the bottom (least
- * significant bits).
- */
- int bi_valid;
- /* Number of valid bits in bi_buf. All bits above the last valid bit
- * are always zero.
- */
-
-} FAR deflate_state;
-
-/* Output a byte on the stream.
- * IN assertion: there is enough room in pending_buf.
- */
-#define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
-
-
-#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
-/* Minimum amount of lookahead, except at the end of the input file.
- * See deflate.c for comments about the MIN_MATCH+1.
- */
-
-#define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
-/* In order to simplify the code, particularly on 16 bit machines, match
- * distances are limited to MAX_DIST instead of WSIZE.
- */
-
- /* in trees.c */
-void _tr_init OF((deflate_state *s));
-int _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
-void _tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len,
- int eof));
-void _tr_align OF((deflate_state *s));
-void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
- int eof));
-
-#define d_code(dist) \
- ((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)])
-/* Mapping from a distance to a distance code. dist is the distance - 1 and
- * must not have side effects. _dist_code[256] and _dist_code[257] are never
- * used.
- */
-
-#ifndef DEBUG
-/* Inline versions of _tr_tally for speed: */
-
-#if defined(GEN_TREES_H) || !defined(STDC)
- extern uch _length_code[];
- extern uch _dist_code[];
-#else
- extern const uch _length_code[];
- extern const uch _dist_code[];
-#endif
-
-# define _tr_tally_lit(s, c, flush) \
- { uch cc = (c); \
- s->d_buf[s->last_lit] = 0; \
- s->l_buf[s->last_lit++] = cc; \
- s->dyn_ltree[cc].Freq++; \
- flush = (s->last_lit == s->lit_bufsize-1); \
- }
-# define _tr_tally_dist(s, distance, length, flush) \
- { uch len = (length); \
- ush dist = (distance); \
- s->d_buf[s->last_lit] = dist; \
- s->l_buf[s->last_lit++] = len; \
- dist--; \
- s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \
- s->dyn_dtree[d_code(dist)].Freq++; \
- flush = (s->last_lit == s->lit_bufsize-1); \
- }
-#else
-# define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
-# define _tr_tally_dist(s, distance, length, flush) \
- flush = _tr_tally(s, distance, length)
-#endif
-
-#endif /* DEFLATE_H */
projects / opencv / blobdiff