be64f2533e15541cd7ffb494b324f51d976ec8ec
[libav.git] / libavcodec / golomb.h
1 /*
2 * exp golomb vlc stuff
3 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
4 * Copyright (c) 2004 Alex Beregszaszi
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg 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.
12 *
13 * FFmpeg 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.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 /**
24 * @file libavcodec/golomb.h
25 * @brief
26 * exp golomb vlc stuff
27 * @author Michael Niedermayer <michaelni@gmx.at> and Alex Beregszaszi
28 */
29
30 #ifndef AVCODEC_GOLOMB_H
31 #define AVCODEC_GOLOMB_H
32
33 #include <stdint.h>
34 #include "bitstream.h"
35 #include "put_bits.h"
36
37 #define INVALID_VLC 0x80000000
38
39 extern const uint8_t ff_golomb_vlc_len[512];
40 extern const uint8_t ff_ue_golomb_vlc_code[512];
41 extern const int8_t ff_se_golomb_vlc_code[512];
42 extern const uint8_t ff_ue_golomb_len[256];
43
44 extern const uint8_t ff_interleaved_golomb_vlc_len[256];
45 extern const uint8_t ff_interleaved_ue_golomb_vlc_code[256];
46 extern const int8_t ff_interleaved_se_golomb_vlc_code[256];
47 extern const uint8_t ff_interleaved_dirac_golomb_vlc_code[256];
48
49
50 /**
51 * read unsigned exp golomb code.
52 */
53 static inline int get_ue_golomb(GetBitContext *gb){
54 unsigned int buf;
55 int log;
56
57 OPEN_READER(re, gb);
58 UPDATE_CACHE(re, gb);
59 buf=GET_CACHE(re, gb);
60
61 if(buf >= (1<<27)){
62 buf >>= 32 - 9;
63 LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
64 CLOSE_READER(re, gb);
65
66 return ff_ue_golomb_vlc_code[buf];
67 }else{
68 log= 2*av_log2(buf) - 31;
69 buf>>= log;
70 buf--;
71 LAST_SKIP_BITS(re, gb, 32 - log);
72 CLOSE_READER(re, gb);
73
74 return buf;
75 }
76 }
77
78 /**
79 * read unsigned exp golomb code, constraint to a max of 31.
80 * the return value is undefined if the stored value exceeds 31.
81 */
82 static inline int get_ue_golomb_31(GetBitContext *gb){
83 unsigned int buf;
84
85 OPEN_READER(re, gb);
86 UPDATE_CACHE(re, gb);
87 buf=GET_CACHE(re, gb);
88
89 buf >>= 32 - 9;
90 LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
91 CLOSE_READER(re, gb);
92
93 return ff_ue_golomb_vlc_code[buf];
94 }
95
96 static inline int svq3_get_ue_golomb(GetBitContext *gb){
97 uint32_t buf;
98
99 OPEN_READER(re, gb);
100 UPDATE_CACHE(re, gb);
101 buf=GET_CACHE(re, gb);
102
103 if(buf&0xAA800000){
104 buf >>= 32 - 8;
105 LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
106 CLOSE_READER(re, gb);
107
108 return ff_interleaved_ue_golomb_vlc_code[buf];
109 }else{
110 int ret = 1;
111
112 while (1) {
113 buf >>= 32 - 8;
114 LAST_SKIP_BITS(re, gb, FFMIN(ff_interleaved_golomb_vlc_len[buf], 8));
115
116 if (ff_interleaved_golomb_vlc_len[buf] != 9){
117 ret <<= (ff_interleaved_golomb_vlc_len[buf] - 1) >> 1;
118 ret |= ff_interleaved_dirac_golomb_vlc_code[buf];
119 break;
120 }
121 ret = (ret << 4) | ff_interleaved_dirac_golomb_vlc_code[buf];
122 UPDATE_CACHE(re, gb);
123 buf = GET_CACHE(re, gb);
124 }
125
126 CLOSE_READER(re, gb);
127 return ret - 1;
128 }
129 }
130
131 /**
132 * read unsigned truncated exp golomb code.
133 */
134 static inline int get_te0_golomb(GetBitContext *gb, int range){
135 assert(range >= 1);
136
137 if(range==1) return 0;
138 else if(range==2) return get_bits1(gb)^1;
139 else return get_ue_golomb(gb);
140 }
141
142 /**
143 * read unsigned truncated exp golomb code.
144 */
145 static inline int get_te_golomb(GetBitContext *gb, int range){
146 assert(range >= 1);
147
148 if(range==2) return get_bits1(gb)^1;
149 else return get_ue_golomb(gb);
150 }
151
152
153 /**
154 * read signed exp golomb code.
155 */
156 static inline int get_se_golomb(GetBitContext *gb){
157 unsigned int buf;
158 int log;
159
160 OPEN_READER(re, gb);
161 UPDATE_CACHE(re, gb);
162 buf=GET_CACHE(re, gb);
163
164 if(buf >= (1<<27)){
165 buf >>= 32 - 9;
166 LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
167 CLOSE_READER(re, gb);
168
169 return ff_se_golomb_vlc_code[buf];
170 }else{
171 log= 2*av_log2(buf) - 31;
172 buf>>= log;
173
174 LAST_SKIP_BITS(re, gb, 32 - log);
175 CLOSE_READER(re, gb);
176
177 if(buf&1) buf= -(buf>>1);
178 else buf= (buf>>1);
179
180 return buf;
181 }
182 }
183
184 static inline int svq3_get_se_golomb(GetBitContext *gb){
185 unsigned int buf;
186 int log;
187
188 OPEN_READER(re, gb);
189 UPDATE_CACHE(re, gb);
190 buf=GET_CACHE(re, gb);
191
192 if(buf&0xAA800000){
193 buf >>= 32 - 8;
194 LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
195 CLOSE_READER(re, gb);
196
197 return ff_interleaved_se_golomb_vlc_code[buf];
198 }else{
199 LAST_SKIP_BITS(re, gb, 8);
200 UPDATE_CACHE(re, gb);
201 buf |= 1 | (GET_CACHE(re, gb) >> 8);
202
203 if((buf & 0xAAAAAAAA) == 0)
204 return INVALID_VLC;
205
206 for(log=31; (buf & 0x80000000) == 0; log--){
207 buf = (buf << 2) - ((buf << log) >> (log - 1)) + (buf >> 30);
208 }
209
210 LAST_SKIP_BITS(re, gb, 63 - 2*log - 8);
211 CLOSE_READER(re, gb);
212
213 return (signed) (((((buf << log) >> log) - 1) ^ -(buf & 0x1)) + 1) >> 1;
214 }
215 }
216
217 static inline int dirac_get_se_golomb(GetBitContext *gb){
218 uint32_t buf;
219 uint32_t ret;
220
221 ret = svq3_get_ue_golomb(gb);
222
223 if (ret) {
224 OPEN_READER(re, gb);
225 UPDATE_CACHE(re, gb);
226 buf = SHOW_SBITS(re, gb, 1);
227 LAST_SKIP_BITS(re, gb, 1);
228 ret = (ret ^ buf) - buf;
229 CLOSE_READER(re, gb);
230 }
231
232 return ret;
233 }
234
235 /**
236 * read unsigned golomb rice code (ffv1).
237 */
238 static inline int get_ur_golomb(GetBitContext *gb, int k, int limit, int esc_len){
239 unsigned int buf;
240 int log;
241
242 OPEN_READER(re, gb);
243 UPDATE_CACHE(re, gb);
244 buf=GET_CACHE(re, gb);
245
246 log= av_log2(buf);
247
248 if(log > 31-limit){
249 buf >>= log - k;
250 buf += (30-log)<<k;
251 LAST_SKIP_BITS(re, gb, 32 + k - log);
252 CLOSE_READER(re, gb);
253
254 return buf;
255 }else{
256 buf >>= 32 - limit - esc_len;
257 LAST_SKIP_BITS(re, gb, esc_len + limit);
258 CLOSE_READER(re, gb);
259
260 return buf + limit - 1;
261 }
262 }
263
264 /**
265 * read unsigned golomb rice code (jpegls).
266 */
267 static inline int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit, int esc_len){
268 unsigned int buf;
269 int log;
270
271 OPEN_READER(re, gb);
272 UPDATE_CACHE(re, gb);
273 buf=GET_CACHE(re, gb);
274
275 log= av_log2(buf);
276
277 if(log - k >= 32-MIN_CACHE_BITS+(MIN_CACHE_BITS==32) && 32-log < limit){
278 buf >>= log - k;
279 buf += (30-log)<<k;
280 LAST_SKIP_BITS(re, gb, 32 + k - log);
281 CLOSE_READER(re, gb);
282
283 return buf;
284 }else{
285 int i;
286 for(i=0; SHOW_UBITS(re, gb, 1) == 0; i++){
287 LAST_SKIP_BITS(re, gb, 1);
288 UPDATE_CACHE(re, gb);
289 }
290 SKIP_BITS(re, gb, 1);
291
292 if(i < limit - 1){
293 if(k){
294 buf = SHOW_UBITS(re, gb, k);
295 LAST_SKIP_BITS(re, gb, k);
296 }else{
297 buf=0;
298 }
299
300 CLOSE_READER(re, gb);
301 return buf + (i<<k);
302 }else if(i == limit - 1){
303 buf = SHOW_UBITS(re, gb, esc_len);
304 LAST_SKIP_BITS(re, gb, esc_len);
305 CLOSE_READER(re, gb);
306
307 return buf + 1;
308 }else
309 return -1;
310 }
311 }
312
313 /**
314 * read signed golomb rice code (ffv1).
315 */
316 static inline int get_sr_golomb(GetBitContext *gb, int k, int limit, int esc_len){
317 int v= get_ur_golomb(gb, k, limit, esc_len);
318
319 v++;
320 if (v&1) return v>>1;
321 else return -(v>>1);
322
323 // return (v>>1) ^ -(v&1);
324 }
325
326 /**
327 * read signed golomb rice code (flac).
328 */
329 static inline int get_sr_golomb_flac(GetBitContext *gb, int k, int limit, int esc_len){
330 int v= get_ur_golomb_jpegls(gb, k, limit, esc_len);
331 return (v>>1) ^ -(v&1);
332 }
333
334 /**
335 * read unsigned golomb rice code (shorten).
336 */
337 static inline unsigned int get_ur_golomb_shorten(GetBitContext *gb, int k){
338 return get_ur_golomb_jpegls(gb, k, INT_MAX, 0);
339 }
340
341 /**
342 * read signed golomb rice code (shorten).
343 */
344 static inline int get_sr_golomb_shorten(GetBitContext* gb, int k)
345 {
346 int uvar = get_ur_golomb_jpegls(gb, k + 1, INT_MAX, 0);
347 if (uvar & 1)
348 return ~(uvar >> 1);
349 else
350 return uvar >> 1;
351 }
352
353
354
355 #ifdef TRACE
356
357 static inline int get_ue(GetBitContext *s, char *file, const char *func, int line){
358 int show= show_bits(s, 24);
359 int pos= get_bits_count(s);
360 int i= get_ue_golomb(s);
361 int len= get_bits_count(s) - pos;
362 int bits= show>>(24-len);
363
364 print_bin(bits, len);
365
366 av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d ue @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
367
368 return i;
369 }
370
371 static inline int get_se(GetBitContext *s, char *file, const char *func, int line){
372 int show= show_bits(s, 24);
373 int pos= get_bits_count(s);
374 int i= get_se_golomb(s);
375 int len= get_bits_count(s) - pos;
376 int bits= show>>(24-len);
377
378 print_bin(bits, len);
379
380 av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d se @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
381
382 return i;
383 }
384
385 static inline int get_te(GetBitContext *s, int r, char *file, const char *func, int line){
386 int show= show_bits(s, 24);
387 int pos= get_bits_count(s);
388 int i= get_te0_golomb(s, r);
389 int len= get_bits_count(s) - pos;
390 int bits= show>>(24-len);
391
392 print_bin(bits, len);
393
394 av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d te @%5d in %s %s:%d\n", bits, len, i, pos, file, func, line);
395
396 return i;
397 }
398
399 #define get_ue_golomb(a) get_ue(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
400 #define get_se_golomb(a) get_se(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
401 #define get_te_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
402 #define get_te0_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
403
404 #endif
405
406 /**
407 * write unsigned exp golomb code.
408 */
409 static inline void set_ue_golomb(PutBitContext *pb, int i){
410 int e;
411
412 assert(i>=0);
413
414 #if 0
415 if(i=0){
416 put_bits(pb, 1, 1);
417 return;
418 }
419 #endif
420 if(i<256)
421 put_bits(pb, ff_ue_golomb_len[i], i+1);
422 else{
423 e= av_log2(i+1);
424
425 put_bits(pb, 2*e+1, i+1);
426 }
427 }
428
429 /**
430 * write truncated unsigned exp golomb code.
431 */
432 static inline void set_te_golomb(PutBitContext *pb, int i, int range){
433 assert(range >= 1);
434 assert(i<=range);
435
436 if(range==2) put_bits(pb, 1, i^1);
437 else set_ue_golomb(pb, i);
438 }
439
440 /**
441 * write signed exp golomb code. 16 bits at most.
442 */
443 static inline void set_se_golomb(PutBitContext *pb, int i){
444 // if (i>32767 || i<-32767)
445 // av_log(NULL,AV_LOG_ERROR,"value out of range %d\n", i);
446 #if 0
447 if(i<=0) i= -2*i;
448 else i= 2*i-1;
449 #elif 1
450 i= 2*i-1;
451 if(i<0) i^= -1; //FIXME check if gcc does the right thing
452 #else
453 i= 2*i-1;
454 i^= (i>>31);
455 #endif
456 set_ue_golomb(pb, i);
457 }
458
459 /**
460 * write unsigned golomb rice code (ffv1).
461 */
462 static inline void set_ur_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len){
463 int e;
464
465 assert(i>=0);
466
467 e= i>>k;
468 if(e<limit){
469 put_bits(pb, e + k + 1, (1<<k) + (i&((1<<k)-1)));
470 }else{
471 put_bits(pb, limit + esc_len, i - limit + 1);
472 }
473 }
474
475 /**
476 * write unsigned golomb rice code (jpegls).
477 */
478 static inline void set_ur_golomb_jpegls(PutBitContext *pb, int i, int k, int limit, int esc_len){
479 int e;
480
481 assert(i>=0);
482
483 e= (i>>k) + 1;
484 if(e<limit){
485 while(e > 31) {
486 put_bits(pb, 31, 0);
487 e -= 31;
488 }
489 put_bits(pb, e, 1);
490 if(k)
491 put_sbits(pb, k, i);
492 }else{
493 while(limit > 31) {
494 put_bits(pb, 31, 0);
495 limit -= 31;
496 }
497 put_bits(pb, limit , 1);
498 put_bits(pb, esc_len, i - 1);
499 }
500 }
501
502 /**
503 * write signed golomb rice code (ffv1).
504 */
505 static inline void set_sr_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len){
506 int v;
507
508 v = -2*i-1;
509 v ^= (v>>31);
510
511 set_ur_golomb(pb, v, k, limit, esc_len);
512 }
513
514 /**
515 * write signed golomb rice code (flac).
516 */
517 static inline void set_sr_golomb_flac(PutBitContext *pb, int i, int k, int limit, int esc_len){
518 int v;
519
520 v = -2*i-1;
521 v ^= (v>>31);
522
523 set_ur_golomb_jpegls(pb, v, k, limit, esc_len);
524 }
525
526 #endif /* AVCODEC_GOLOMB_H */