3 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
4 * Copyright (c) 2004 Alex Beregszaszi
6 * This file is part of Libav.
8 * Libav is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * Libav is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with Libav; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 * exp golomb vlc stuff
27 * @author Michael Niedermayer <michaelni@gmx.at> and Alex Beregszaszi
30 #ifndef AVCODEC_GOLOMB_H
31 #define AVCODEC_GOLOMB_H
38 #define INVALID_VLC 0x80000000
40 extern const uint8_t ff_golomb_vlc_len[512];
41 extern const uint8_t ff_ue_golomb_vlc_code[512];
42 extern const int8_t ff_se_golomb_vlc_code[512];
43 extern const uint8_t ff_ue_golomb_len[256];
45 extern const uint8_t ff_interleaved_golomb_vlc_len[256];
46 extern const uint8_t ff_interleaved_ue_golomb_vlc_code[256];
47 extern const int8_t ff_interleaved_se_golomb_vlc_code[256];
48 extern const uint8_t ff_interleaved_dirac_golomb_vlc_code[256];
51 * read unsigned exp golomb code.
53 static inline int get_ue_golomb(GetBitContext *gb)
59 buf = GET_CACHE(re, gb);
61 if (buf >= (1 << 27)) {
63 LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
66 return ff_ue_golomb_vlc_code[buf];
68 int log = 2 * av_log2(buf) - 31;
71 LAST_SKIP_BITS(re, gb, 32 - log);
79 * Read an unsigned Exp-Golomb code in the range 0 to UINT32_MAX-1.
81 static inline unsigned get_ue_golomb_long(GetBitContext *gb)
85 buf = show_bits_long(gb, 32);
86 log = 31 - av_log2(buf);
87 skip_bits_long(gb, log);
89 return get_bits_long(gb, log + 1) - 1;
93 * read unsigned exp golomb code, constraint to a max of 31.
94 * the return value is undefined if the stored value exceeds 31.
96 static inline int get_ue_golomb_31(GetBitContext *gb)
101 UPDATE_CACHE(re, gb);
102 buf = GET_CACHE(re, gb);
105 LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
106 CLOSE_READER(re, gb);
108 return ff_ue_golomb_vlc_code[buf];
111 static inline unsigned svq3_get_ue_golomb(GetBitContext *gb)
116 UPDATE_CACHE(re, gb);
117 buf = GET_CACHE(re, gb);
119 if (buf & 0xAA800000) {
121 LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
122 CLOSE_READER(re, gb);
124 return ff_interleaved_ue_golomb_vlc_code[buf];
130 LAST_SKIP_BITS(re, gb,
131 FFMIN(ff_interleaved_golomb_vlc_len[buf], 8));
133 if (ff_interleaved_golomb_vlc_len[buf] != 9) {
134 ret <<= (ff_interleaved_golomb_vlc_len[buf] - 1) >> 1;
135 ret |= ff_interleaved_dirac_golomb_vlc_code[buf];
138 ret = (ret << 4) | ff_interleaved_dirac_golomb_vlc_code[buf];
139 UPDATE_CACHE(re, gb);
140 buf = GET_CACHE(re, gb);
141 } while (BITS_AVAILABLE(re, gb));
143 CLOSE_READER(re, gb);
149 * read unsigned truncated exp golomb code.
151 static inline int get_te0_golomb(GetBitContext *gb, int range)
158 return get_bits1(gb) ^ 1;
160 return get_ue_golomb(gb);
164 * read unsigned truncated exp golomb code.
166 static inline int get_te_golomb(GetBitContext *gb, int range)
171 return get_bits1(gb) ^ 1;
173 return get_ue_golomb(gb);
177 * read signed exp golomb code.
179 static inline int get_se_golomb(GetBitContext *gb)
184 UPDATE_CACHE(re, gb);
185 buf = GET_CACHE(re, gb);
187 if (buf >= (1 << 27)) {
189 LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
190 CLOSE_READER(re, gb);
192 return ff_se_golomb_vlc_code[buf];
194 int log = 2 * av_log2(buf) - 31;
197 LAST_SKIP_BITS(re, gb, 32 - log);
198 CLOSE_READER(re, gb);
209 static inline int get_se_golomb_long(GetBitContext *gb)
211 unsigned int buf = get_ue_golomb_long(gb);
214 buf = (buf + 1) >> 1;
221 static inline int svq3_get_se_golomb(GetBitContext *gb)
226 UPDATE_CACHE(re, gb);
227 buf = GET_CACHE(re, gb);
229 if (buf & 0xAA800000) {
231 LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
232 CLOSE_READER(re, gb);
234 return ff_interleaved_se_golomb_vlc_code[buf];
237 LAST_SKIP_BITS(re, gb, 8);
238 UPDATE_CACHE(re, gb);
239 buf |= 1 | (GET_CACHE(re, gb) >> 8);
241 if ((buf & 0xAAAAAAAA) == 0)
244 for (log = 31; (buf & 0x80000000) == 0; log--)
245 buf = (buf << 2) - ((buf << log) >> (log - 1)) + (buf >> 30);
247 LAST_SKIP_BITS(re, gb, 63 - 2 * log - 8);
248 CLOSE_READER(re, gb);
250 return (signed) (((((buf << log) >> log) - 1) ^ -(buf & 0x1)) + 1) >> 1;
254 static inline int dirac_get_se_golomb(GetBitContext *gb)
256 uint32_t ret = svq3_get_ue_golomb(gb);
261 UPDATE_CACHE(re, gb);
262 buf = SHOW_SBITS(re, gb, 1);
263 LAST_SKIP_BITS(re, gb, 1);
264 ret = (ret ^ buf) - buf;
265 CLOSE_READER(re, gb);
272 * read unsigned golomb rice code (ffv1).
274 static inline int get_ur_golomb(GetBitContext *gb, int k, int limit,
281 UPDATE_CACHE(re, gb);
282 buf = GET_CACHE(re, gb);
286 if (log > 31 - limit) {
288 buf += (30 - log) << k;
289 LAST_SKIP_BITS(re, gb, 32 + k - log);
290 CLOSE_READER(re, gb);
294 LAST_SKIP_BITS(re, gb, limit);
295 UPDATE_CACHE(re, gb);
297 buf = SHOW_UBITS(re, gb, esc_len);
299 LAST_SKIP_BITS(re, gb, esc_len);
300 CLOSE_READER(re, gb);
302 return buf + limit - 1;
307 * read unsigned golomb rice code (jpegls).
309 static inline int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit,
316 UPDATE_CACHE(re, gb);
317 buf = GET_CACHE(re, gb);
321 if (log - k >= 32 - MIN_CACHE_BITS + (MIN_CACHE_BITS == 32) &&
324 buf += (30 - log) << k;
325 LAST_SKIP_BITS(re, gb, 32 + k - log);
326 CLOSE_READER(re, gb);
331 for (i = 0; i < limit && SHOW_UBITS(re, gb, 1) == 0 && BITS_AVAILABLE(re, gb); i++) {
332 LAST_SKIP_BITS(re, gb, 1);
333 UPDATE_CACHE(re, gb);
335 SKIP_BITS(re, gb, 1);
339 buf = SHOW_UBITS(re, gb, k);
340 LAST_SKIP_BITS(re, gb, k);
345 CLOSE_READER(re, gb);
346 return buf + (i << k);
347 } else if (i == limit - 1) {
348 buf = SHOW_UBITS(re, gb, esc_len);
349 LAST_SKIP_BITS(re, gb, esc_len);
350 CLOSE_READER(re, gb);
359 * read signed golomb rice code (ffv1).
361 static inline int get_sr_golomb(GetBitContext *gb, int k, int limit,
364 int v = get_ur_golomb(gb, k, limit, esc_len);
372 // return (v>>1) ^ -(v&1);
376 * read signed golomb rice code (flac).
378 static inline int get_sr_golomb_flac(GetBitContext *gb, int k, int limit,
381 int v = get_ur_golomb_jpegls(gb, k, limit, esc_len);
382 return (v >> 1) ^ -(v & 1);
386 * read unsigned golomb rice code (shorten).
388 static inline unsigned int get_ur_golomb_shorten(GetBitContext *gb, int k)
390 return get_ur_golomb_jpegls(gb, k, INT_MAX, 0);
394 * read signed golomb rice code (shorten).
396 static inline int get_sr_golomb_shorten(GetBitContext *gb, int k)
398 int uvar = get_ur_golomb_jpegls(gb, k + 1, INT_MAX, 0);
407 static inline int get_ue(GetBitContext *s, const char *file, const char *func,
410 int show = show_bits(s, 24);
411 int pos = get_bits_count(s);
412 int i = get_ue_golomb(s);
413 int len = get_bits_count(s) - pos;
414 int bits = show >> (24 - len);
416 print_bin(bits, len);
418 av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d ue @%5d in %s %s:%d\n",
419 bits, len, i, pos, file, func, line);
424 static inline int get_se(GetBitContext *s, const char *file, const char *func,
427 int show = show_bits(s, 24);
428 int pos = get_bits_count(s);
429 int i = get_se_golomb(s);
430 int len = get_bits_count(s) - pos;
431 int bits = show >> (24 - len);
433 print_bin(bits, len);
435 av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d se @%5d in %s %s:%d\n",
436 bits, len, i, pos, file, func, line);
441 static inline int get_te(GetBitContext *s, int r, char *file, const char *func,
444 int show = show_bits(s, 24);
445 int pos = get_bits_count(s);
446 int i = get_te0_golomb(s, r);
447 int len = get_bits_count(s) - pos;
448 int bits = show >> (24 - len);
450 print_bin(bits, len);
452 av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d te @%5d in %s %s:%d\n",
453 bits, len, i, pos, file, func, line);
458 #define get_ue_golomb(a) get_ue(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
459 #define get_se_golomb(a) get_se(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
460 #define get_te_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
461 #define get_te0_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
466 * write unsigned exp golomb code.
468 static inline void set_ue_golomb(PutBitContext *pb, int i)
479 put_bits(pb, ff_ue_golomb_len[i], i + 1);
481 int e = av_log2(i + 1);
482 put_bits(pb, 2 * e + 1, i + 1);
487 * write truncated unsigned exp golomb code.
489 static inline void set_te_golomb(PutBitContext *pb, int i, int range)
495 put_bits(pb, 1, i ^ 1);
497 set_ue_golomb(pb, i);
501 * write signed exp golomb code. 16 bits at most.
503 static inline void set_se_golomb(PutBitContext *pb, int i)
513 i ^= -1; //FIXME check if gcc does the right thing
518 set_ue_golomb(pb, i);
522 * write unsigned golomb rice code (ffv1).
524 static inline void set_ur_golomb(PutBitContext *pb, int i, int k, int limit,
533 put_bits(pb, e + k + 1, (1 << k) + (i & ((1 << k) - 1)));
535 put_bits(pb, limit + esc_len, i - limit + 1);
539 * write unsigned golomb rice code (jpegls).
541 static inline void set_ur_golomb_jpegls(PutBitContext *pb, int i, int k,
542 int limit, int esc_len)
562 put_bits(pb, limit, 1);
563 put_bits(pb, esc_len, i - 1);
568 * write signed golomb rice code (ffv1).
570 static inline void set_sr_golomb(PutBitContext *pb, int i, int k, int limit,
578 set_ur_golomb(pb, v, k, limit, esc_len);
582 * write signed golomb rice code (flac).
584 static inline void set_sr_golomb_flac(PutBitContext *pb, int i, int k,
585 int limit, int esc_len)
592 set_ur_golomb_jpegls(pb, v, k, limit, esc_len);
595 #endif /* AVCODEC_GOLOMB_H */