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Diffstat (limited to 'contrib/ffmpeg/libavcodec/lzwenc.c')
-rw-r--r--contrib/ffmpeg/libavcodec/lzwenc.c262
1 files changed, 0 insertions, 262 deletions
diff --git a/contrib/ffmpeg/libavcodec/lzwenc.c b/contrib/ffmpeg/libavcodec/lzwenc.c
deleted file mode 100644
index 3a24af347..000000000
--- a/contrib/ffmpeg/libavcodec/lzwenc.c
+++ /dev/null
@@ -1,262 +0,0 @@
-/*
- * LZW encoder
- * Copyright (c) 2007 Bartlomiej Wolowiec
- *
- * This file is part of FFmpeg.
- *
- * FFmpeg is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * FFmpeg is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-/**
- * LZW encoder
- * @file lzwenc.c
- * @author Bartlomiej Wolowiec
- */
-
-#include "avcodec.h"
-#include "bitstream.h"
-#include "lzw.h"
-
-#define LZW_MAXBITS 12
-#define LZW_SIZTABLE (1<<LZW_MAXBITS)
-#define LZW_HASH_SIZE 16411
-#define LZW_HASH_SHIFT 6
-
-#define LZW_PREFIX_EMPTY -1
-#define LZW_PREFIX_FREE -2
-
-/** One code in hash table */
-typedef struct Code{
- /// Hash code of prefix, LZW_PREFIX_EMPTY if empty prefix, or LZW_PREFIX_FREE if no code
- int hash_prefix;
- int code; ///< LZW code
- uint8_t suffix; ///< Last character in code block
-}Code;
-
-/** LZW encode state */
-typedef struct LZWEncodeState {
- int clear_code; ///< Value of clear code
- int end_code; ///< Value of end code
- Code tab[LZW_HASH_SIZE]; ///< Hash table
- int tabsize; ///< Number of values in hash table
- int bits; ///< Actual bits code
- int bufsize; ///< Size of output buffer
- PutBitContext pb; ///< Put bit context for output
- int maxbits; ///< Max bits code
- int maxcode; ///< Max value of code
- int output_bytes; ///< Number of written bytes
- int last_code; ///< Value of last output code or LZW_PREFIX_EMPTY
-}LZWEncodeState;
-
-
-const int ff_lzw_encode_state_size = sizeof(LZWEncodeState);
-
-/**
- * Hash function adding character
- * @param head LZW code for prefix
- * @param add Character to add
- * @return New hash value
- */
-static inline int hash(int head, const int add)
-{
- head ^= (add << LZW_HASH_SHIFT);
- if (head >= LZW_HASH_SIZE)
- head -= LZW_HASH_SIZE;
- assert(head >= 0 && head < LZW_HASH_SIZE);
- return head;
-}
-
-/**
- * Hash function calculates next hash value
- * @param head Actual hash code
- * @param offset Offset calculated by hashOffset
- * @return New hash value
- */
-static inline int hashNext(int head, const int offset)
-{
- head -= offset;
- if(head < 0)
- head += LZW_HASH_SIZE;
- return head;
-}
-
-/**
- * Hash function calculates hash offset
- * @param head Actual hash code
- * @return Hash offset
- */
-static inline int hashOffset(const int head)
-{
- return head ? LZW_HASH_SIZE - head : 1;
-}
-
-/**
- * Write one code to stream
- * @param s LZW state
- * @param c code to write
- */
-static inline void writeCode(LZWEncodeState * s, int c)
-{
- assert(0 <= c && c < 1 << s->bits);
- put_bits(&s->pb, s->bits, c);
-}
-
-
-/**
- * Find LZW code for block
- * @param s LZW state
- * @param c Last character in block
- * @param hash_prefix LZW code for prefix
- * @return LZW code for block or -1 if not found in table
- */
-static inline int findCode(LZWEncodeState * s, uint8_t c, int hash_prefix)
-{
- int h = hash(FFMAX(hash_prefix, 0), c);
- int hash_offset = hashOffset(h);
-
- while (s->tab[h].hash_prefix != LZW_PREFIX_FREE) {
- if ((s->tab[h].suffix == c)
- && (s->tab[h].hash_prefix == hash_prefix))
- return h;
- h = hashNext(h, hash_offset);
- }
-
- return h;
-}
-
-/**
- * Add block to LZW code table
- * @param s LZW state
- * @param c Last character in block
- * @param hash_prefix LZW code for prefix
- * @param hash_code LZW code for bytes block
- */
-static inline void addCode(LZWEncodeState * s, uint8_t c, int hash_prefix, int hash_code)
-{
- s->tab[hash_code].code = s->tabsize;
- s->tab[hash_code].suffix = c;
- s->tab[hash_code].hash_prefix = hash_prefix;
-
- s->tabsize++;
-
- if (s->tabsize >= 1 << s->bits)
- s->bits++;
-}
-
-/**
- * Clear LZW code table
- * @param s LZW state
- */
-static void clearTable(LZWEncodeState * s)
-{
- int i, h;
-
- writeCode(s, s->clear_code);
- s->bits = 9;
- for (i = 0; i < LZW_HASH_SIZE; i++) {
- s->tab[i].hash_prefix = LZW_PREFIX_FREE;
- }
- for (i = 0; i < 256; i++) {
- h = hash(0, i);
- s->tab[h].code = i;
- s->tab[h].suffix = i;
- s->tab[h].hash_prefix = LZW_PREFIX_EMPTY;
- }
- s->tabsize = 258;
-}
-
-/**
- * Calculate number of bytes written
- * @param s LZW encode state
- * @return Number of bytes written
- */
-static int writtenBytes(LZWEncodeState *s){
- int ret = put_bits_count(&s->pb) >> 3;
- ret -= s->output_bytes;
- s->output_bytes += ret;
- return ret;
-}
-
-/**
- * Initialize LZW encoder. Please set s->clear_code, s->end_code and s->maxbits before run.
- * @param s LZW state
- * @param outbuf Output buffer
- * @param outsize Size of output buffer
- * @param maxbits Maximum length of code
- */
-void ff_lzw_encode_init(LZWEncodeState * s, uint8_t * outbuf, int outsize, int maxbits)
-{
- s->clear_code = 256;
- s->end_code = 257;
- s->maxbits = maxbits;
- init_put_bits(&s->pb, outbuf, outsize);
- s->bufsize = outsize;
- assert(9 <= s->maxbits && s->maxbits <= s->maxbits);
- s->maxcode = 1 << s->maxbits;
- s->output_bytes = 0;
- s->last_code = LZW_PREFIX_EMPTY;
- s->bits = 9;
-}
-
-/**
- * LZW main compress function
- * @param s LZW state
- * @param inbuf Input buffer
- * @param insize Size of input buffer
- * @return Number of bytes written or -1 on error
- */
-int ff_lzw_encode(LZWEncodeState * s, const uint8_t * inbuf, int insize)
-{
- int i;
-
- if(insize * 3 > (s->bufsize - s->output_bytes) * 2){
- return -1;
- }
-
- if (s->last_code == LZW_PREFIX_EMPTY)
- clearTable(s);
-
- for (i = 0; i < insize; i++) {
- uint8_t c = *inbuf++;
- int code = findCode(s, c, s->last_code);
- if (s->tab[code].hash_prefix == LZW_PREFIX_FREE) {
- writeCode(s, s->last_code);
- addCode(s, c, s->last_code, code);
- code= hash(0, c);
- }
- s->last_code = s->tab[code].code;
- if (s->tabsize >= s->maxcode - 1) {
- clearTable(s);
- }
- }
-
- return writtenBytes(s);
-}
-
-/**
- * Write end code and flush bitstream
- * @param s LZW state
- * @return Number of bytes written or -1 on error
- */
-int ff_lzw_encode_flush(LZWEncodeState * s)
-{
- if (s->last_code != -1)
- writeCode(s, s->last_code);
- writeCode(s, s->end_code);
- flush_put_bits(&s->pb);
- s->last_code = -1;
-
- return writtenBytes(s);
-}
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