FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/golomb.h
Date: 2024-07-24 19:24:46
Exec Total Coverage
Lines: 167 169 98.8%
Functions: 14 14 100.0%
Branches: 41 46 89.1%

Line Branch Exec Source
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
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
35 #include "get_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
43 extern const uint8_t ff_interleaved_golomb_vlc_len[256];
44 extern const uint8_t ff_interleaved_ue_golomb_vlc_code[256];
45 extern const int8_t ff_interleaved_se_golomb_vlc_code[256];
46 extern const uint8_t ff_interleaved_dirac_golomb_vlc_code[256];
47
48 /**
49 * Read an unsigned Exp-Golomb code in the range 0 to 8190.
50 *
51 * @returns the read value or a negative error code.
52 */
53 30769430 static inline int get_ue_golomb(GetBitContext *gb)
54 {
55 unsigned int buf;
56
57 #if CACHED_BITSTREAM_READER
58 buf = show_bits_long(gb, 32);
59
60 if (buf >= (1 << 27)) {
61 buf >>= 32 - 9;
62 skip_bits_long(gb, ff_golomb_vlc_len[buf]);
63
64 return ff_ue_golomb_vlc_code[buf];
65 } else {
66 int log = 2 * av_log2(buf) - 31;
67
68 skip_bits_long(gb, 32 - log);
69 if (log < 7)
70 return AVERROR_INVALIDDATA;
71 buf >>= log;
72 buf--;
73
74 return buf;
75 }
76 #else
77 30769430 OPEN_READER(re, gb);
78 30769430 UPDATE_CACHE(re, gb);
79 30769430 buf = GET_CACHE(re, gb);
80
81
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30769430 if (buf >= (1 << 27)) {
82 29679011 buf >>= 32 - 9;
83 29679011 LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
84 29679011 CLOSE_READER(re, gb);
85
86 29679011 return ff_ue_golomb_vlc_code[buf];
87 } else {
88 1090419 int log = 2 * av_log2(buf) - 31;
89 1090419 LAST_SKIP_BITS(re, gb, 32 - log);
90 1090419 CLOSE_READER(re, gb);
91
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1090419 if (log < 7)
92 3 return AVERROR_INVALIDDATA;
93 1090416 buf >>= log;
94 1090416 buf--;
95
96 1090416 return buf;
97 }
98 #endif
99 }
100
101 /**
102 * Read an unsigned Exp-Golomb code in the range 0 to UINT32_MAX-1.
103 */
104 2827442 static inline unsigned get_ue_golomb_long(GetBitContext *gb)
105 {
106 unsigned buf, log;
107
108 2827442 buf = show_bits_long(gb, 32);
109 2827442 log = 31 - av_log2(buf);
110 2827442 skip_bits_long(gb, log);
111
112 2827442 return get_bits_long(gb, log + 1) - 1;
113 }
114
115 /**
116 * read unsigned exp golomb code, constraint to a max of 31.
117 * If the value encountered is not in 0..31, the return value
118 * is outside the range 0..30.
119 */
120 5589788 static inline int get_ue_golomb_31(GetBitContext *gb)
121 {
122 unsigned int buf;
123
124 #if CACHED_BITSTREAM_READER
125 buf = show_bits_long(gb, 32);
126
127 buf >>= 32 - 9;
128 skip_bits_long(gb, ff_golomb_vlc_len[buf]);
129 #else
130
131 5589788 OPEN_READER(re, gb);
132 5589788 UPDATE_CACHE(re, gb);
133 5589788 buf = GET_CACHE(re, gb);
134
135 5589788 buf >>= 32 - 9;
136 5589788 LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
137 5589788 CLOSE_READER(re, gb);
138 #endif
139
140 5589788 return ff_ue_golomb_vlc_code[buf];
141 }
142
143 13660458 static inline unsigned get_interleaved_ue_golomb(GetBitContext *gb)
144 {
145 uint32_t buf;
146
147 #if CACHED_BITSTREAM_READER
148 buf = show_bits_long(gb, 32);
149
150 if (buf & 0xAA800000) {
151 buf >>= 32 - 8;
152 skip_bits_long(gb, ff_interleaved_golomb_vlc_len[buf]);
153
154 return ff_interleaved_ue_golomb_vlc_code[buf];
155 } else {
156 unsigned ret = 1;
157
158 do {
159 buf >>= 32 - 8;
160 skip_bits_long(gb, FFMIN(ff_interleaved_golomb_vlc_len[buf], 8));
161
162 if (ff_interleaved_golomb_vlc_len[buf] != 9) {
163 ret <<= (ff_interleaved_golomb_vlc_len[buf] - 1) >> 1;
164 ret |= ff_interleaved_dirac_golomb_vlc_code[buf];
165 break;
166 }
167 ret = (ret << 4) | ff_interleaved_dirac_golomb_vlc_code[buf];
168 buf = show_bits_long(gb, 32);
169 } while (get_bits_left(gb) > 0);
170
171 return ret - 1;
172 }
173 #else
174 13660458 OPEN_READER(re, gb);
175 13660458 UPDATE_CACHE(re, gb);
176 13660458 buf = GET_CACHE(re, gb);
177
178
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13660458 if (buf & 0xAA800000) {
179 13492466 buf >>= 32 - 8;
180 13492466 LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
181 13492466 CLOSE_READER(re, gb);
182
183 13492466 return ff_interleaved_ue_golomb_vlc_code[buf];
184 } else {
185 167992 unsigned ret = 1;
186
187 do {
188 340579 buf >>= 32 - 8;
189 340579 LAST_SKIP_BITS(re, gb,
190 FFMIN(ff_interleaved_golomb_vlc_len[buf], 8));
191
192
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340579 if (ff_interleaved_golomb_vlc_len[buf] != 9) {
193 167992 ret <<= (ff_interleaved_golomb_vlc_len[buf] - 1) >> 1;
194 167992 ret |= ff_interleaved_dirac_golomb_vlc_code[buf];
195 167992 break;
196 }
197 172587 ret = (ret << 4) | ff_interleaved_dirac_golomb_vlc_code[buf];
198 172587 UPDATE_CACHE(re, gb);
199 172587 buf = GET_CACHE(re, gb);
200
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172587 } while (ret<0x8000000U && BITS_AVAILABLE(re, gb));
201
202 167992 CLOSE_READER(re, gb);
203 167992 return ret - 1;
204 }
205 #endif
206 }
207
208 /**
209 * read unsigned truncated exp golomb code.
210 */
211 static inline int get_te0_golomb(GetBitContext *gb, int range)
212 {
213 av_assert2(range >= 1);
214
215 if (range == 1)
216 return 0;
217 else if (range == 2)
218 return get_bits1(gb) ^ 1;
219 else
220 return get_ue_golomb(gb);
221 }
222
223 /**
224 * read unsigned truncated exp golomb code.
225 */
226 static inline int get_te_golomb(GetBitContext *gb, int range)
227 {
228 av_assert2(range >= 1);
229
230 if (range == 2)
231 return get_bits1(gb) ^ 1;
232 else
233 return get_ue_golomb(gb);
234 }
235
236 /**
237 * read signed exp golomb code.
238 */
239 16481377 static inline int get_se_golomb(GetBitContext *gb)
240 {
241 unsigned int buf;
242
243 #if CACHED_BITSTREAM_READER
244 buf = show_bits_long(gb, 32);
245
246 if (buf >= (1 << 27)) {
247 buf >>= 32 - 9;
248 skip_bits_long(gb, ff_golomb_vlc_len[buf]);
249
250 return ff_se_golomb_vlc_code[buf];
251 } else {
252 int log = 2 * av_log2(buf) - 31;
253 buf >>= log;
254
255 skip_bits_long(gb, 32 - log);
256
257 if (buf & 1)
258 buf = -(buf >> 1);
259 else
260 buf = (buf >> 1);
261
262 return buf;
263 }
264 #else
265 16481377 OPEN_READER(re, gb);
266 16481377 UPDATE_CACHE(re, gb);
267 16481377 buf = GET_CACHE(re, gb);
268
269
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16481377 if (buf >= (1 << 27)) {
270 15758749 buf >>= 32 - 9;
271 15758749 LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
272 15758749 CLOSE_READER(re, gb);
273
274 15758749 return ff_se_golomb_vlc_code[buf];
275 } else {
276 722628 int log = av_log2(buf), sign;
277 722628 LAST_SKIP_BITS(re, gb, 31 - log);
278 722628 UPDATE_CACHE(re, gb);
279 722628 buf = GET_CACHE(re, gb);
280
281 722628 buf >>= log;
282
283 722628 LAST_SKIP_BITS(re, gb, 32 - log);
284 722628 CLOSE_READER(re, gb);
285
286 722628 sign = -(buf & 1);
287 722628 buf = ((buf >> 1) ^ sign) - sign;
288
289 722628 return buf;
290 }
291 #endif
292 }
293
294 394 static inline int get_se_golomb_long(GetBitContext *gb)
295 {
296 394 unsigned int buf = get_ue_golomb_long(gb);
297 394 int sign = (buf & 1) - 1;
298 394 return ((buf >> 1) ^ sign) + 1;
299 }
300
301 1314739 static inline int get_interleaved_se_golomb(GetBitContext *gb)
302 {
303 unsigned int buf;
304
305 #if CACHED_BITSTREAM_READER
306 buf = show_bits_long(gb, 32);
307
308 if (buf & 0xAA800000) {
309 buf >>= 32 - 8;
310 skip_bits_long(gb, ff_interleaved_golomb_vlc_len[buf]);
311
312 return ff_interleaved_se_golomb_vlc_code[buf];
313 } else {
314 int log;
315 skip_bits(gb, 8);
316 buf |= 1 | show_bits(gb, 24);
317
318 if ((buf & 0xAAAAAAAA) == 0)
319 return INVALID_VLC;
320
321 for (log = 31; (buf & 0x80000000) == 0; log--)
322 buf = (buf << 2) - ((buf << log) >> (log - 1)) + (buf >> 30);
323
324 skip_bits_long(gb, 63 - 2 * log - 8);
325
326 return (signed) (((((buf << log) >> log) - 1) ^ -(buf & 0x1)) + 1) >> 1;
327 }
328 #else
329 1314739 OPEN_READER(re, gb);
330 1314739 UPDATE_CACHE(re, gb);
331 1314739 buf = GET_CACHE(re, gb);
332
333
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1314739 if (buf & 0xAA800000) {
334 1265588 buf >>= 32 - 8;
335 1265588 LAST_SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
336 1265588 CLOSE_READER(re, gb);
337
338 1265588 return ff_interleaved_se_golomb_vlc_code[buf];
339 } else {
340 int log;
341 49151 LAST_SKIP_BITS(re, gb, 8);
342 49151 UPDATE_CACHE(re, gb);
343 49151 buf |= 1 | (GET_CACHE(re, gb) >> 8);
344
345
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49151 if ((buf & 0xAAAAAAAA) == 0)
346 return INVALID_VLC;
347
348
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326598 for (log = 31; (buf & 0x80000000) == 0; log--)
349 277447 buf = (buf << 2) - ((buf << log) >> (log - 1)) + (buf >> 30);
350
351 49151 LAST_SKIP_BITS(re, gb, 63 - 2 * log - 8);
352 49151 CLOSE_READER(re, gb);
353
354 49151 return (signed) (((((buf << log) >> log) - 1) ^ -(buf & 0x1)) + 1) >> 1;
355 }
356 #endif
357 }
358
359 1949306 static inline int dirac_get_se_golomb(GetBitContext *gb)
360 {
361 1949306 uint32_t ret = get_interleaved_ue_golomb(gb);
362
363
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1949306 if (ret) {
364 336860 int sign = -get_bits1(gb);
365 336860 ret = (ret ^ sign) - sign;
366 }
367
368 1949306 return ret;
369 }
370
371 /**
372 * read unsigned golomb rice code (ffv1).
373 */
374 144478585 static inline int get_ur_golomb(GetBitContext *gb, int k, int limit,
375 int esc_len)
376 {
377 unsigned int buf;
378 int log;
379
380 #if CACHED_BITSTREAM_READER
381 buf = show_bits_long(gb, 32);
382
383 log = av_log2(buf);
384
385 if (log > 31 - limit) {
386 buf >>= log - k;
387 buf += (30 - log) << k;
388 skip_bits_long(gb, 32 + k - log);
389
390 return buf;
391 } else {
392 skip_bits_long(gb, limit);
393 buf = get_bits_long(gb, esc_len);
394
395 return buf + limit - 1;
396 }
397 #else
398 144478585 OPEN_READER(re, gb);
399 144478585 UPDATE_CACHE(re, gb);
400 144478585 buf = GET_CACHE(re, gb);
401
402 144478585 log = av_log2(buf);
403
404
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144478585 if (log > 31 - limit) {
405 av_assert2(log >= k);
406 143777076 buf >>= log - k;
407 143777076 buf += (30U - log) << k;
408 143777076 LAST_SKIP_BITS(re, gb, 32 + k - log);
409 143777076 CLOSE_READER(re, gb);
410
411 143777076 return buf;
412 } else {
413 701509 LAST_SKIP_BITS(re, gb, limit);
414 701509 UPDATE_CACHE(re, gb);
415
416 701509 buf = SHOW_UBITS(re, gb, esc_len);
417
418 701509 LAST_SKIP_BITS(re, gb, esc_len);
419 701509 CLOSE_READER(re, gb);
420
421 701509 return buf + limit - 1;
422 }
423 #endif
424 }
425
426 /**
427 * read unsigned golomb rice code (jpegls).
428 *
429 * @returns -1 on error
430 */
431 106528662 static inline int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit,
432 int esc_len)
433 {
434 unsigned int buf;
435 int log;
436
437 #if CACHED_BITSTREAM_READER
438 buf = show_bits_long(gb, 32);
439
440 log = av_log2(buf);
441
442 if (log - k >= 1 && 32 - log < limit) {
443 buf >>= log - k;
444 buf += (30 - log) << k;
445 skip_bits_long(gb, 32 + k - log);
446
447 return buf;
448 } else {
449 int i;
450 for (i = 0;
451 i < limit && get_bits1(gb) == 0 && get_bits_left(gb) > 0;
452 i++);
453
454 if (i < limit - 1) {
455 buf = get_bits_long(gb, k);
456
457 return buf + (i << k);
458 } else if (i == limit - 1) {
459 buf = get_bits_long(gb, esc_len);
460
461 return buf + 1;
462 } else
463 return -1;
464 }
465 #else
466 106528662 OPEN_READER(re, gb);
467 106528662 UPDATE_CACHE(re, gb);
468 106528662 buf = GET_CACHE(re, gb);
469
470 106528662 log = av_log2(buf);
471
472 av_assert2(k <= 31);
473
474
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106528662 if (log - k >= 32 - MIN_CACHE_BITS + (MIN_CACHE_BITS == 32) &&
475
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106451000 32 - log < limit) {
476 106408752 buf >>= log - k;
477 106408752 buf += (30U - log) << k;
478 106408752 LAST_SKIP_BITS(re, gb, 32 + k - log);
479 106408752 CLOSE_READER(re, gb);
480
481 106408752 return buf;
482 } else {
483 int i;
484
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120429 for (i = 0; i + MIN_CACHE_BITS <= limit && SHOW_UBITS(re, gb, MIN_CACHE_BITS) == 0; i += MIN_CACHE_BITS) {
485
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520 if (gb->size_in_bits <= re_index) {
486 1 CLOSE_READER(re, gb);
487 1 return -1;
488 }
489 519 LAST_SKIP_BITS(re, gb, MIN_CACHE_BITS);
490 519 UPDATE_CACHE(re, gb);
491 }
492
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2231498 for (; i < limit && SHOW_UBITS(re, gb, 1) == 0; i++) {
493 2111589 SKIP_BITS(re, gb, 1);
494 }
495 119909 LAST_SKIP_BITS(re, gb, 1);
496 119909 UPDATE_CACHE(re, gb);
497
498
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119909 if (i < limit - 1) {
499
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31630 if (k) {
500
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31457 if (k > MIN_CACHE_BITS - 1) {
501 17215 buf = SHOW_UBITS(re, gb, 16) << (k-16);
502 17215 LAST_SKIP_BITS(re, gb, 16);
503 17215 UPDATE_CACHE(re, gb);
504 17215 buf |= SHOW_UBITS(re, gb, k-16);
505 17215 LAST_SKIP_BITS(re, gb, k-16);
506 } else {
507 14242 buf = SHOW_UBITS(re, gb, k);
508 14242 LAST_SKIP_BITS(re, gb, k);
509 }
510 } else {
511 173 buf = 0;
512 }
513
514 31630 buf += ((SUINT)i << k);
515
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88279 } else if (i == limit - 1) {
516 88279 buf = SHOW_UBITS(re, gb, esc_len);
517 88279 LAST_SKIP_BITS(re, gb, esc_len);
518
519 88279 buf ++;
520 } else {
521 buf = -1;
522 }
523 119909 CLOSE_READER(re, gb);
524 119909 return buf;
525 }
526 #endif
527 }
528
529 /**
530 * read signed golomb rice code (ffv1).
531 */
532 144478585 static inline int get_sr_golomb(GetBitContext *gb, int k, int limit,
533 int esc_len)
534 {
535 144478585 unsigned v = get_ur_golomb(gb, k, limit, esc_len);
536 144478585 return (v >> 1) ^ -(v & 1);
537 }
538
539 /**
540 * read signed golomb rice code (flac).
541 *
542 * @returns INT_MIN on error
543 */
544 57934362 static inline int get_sr_golomb_flac(GetBitContext *gb, int k, int limit,
545 int esc_len)
546 {
547 57934362 unsigned v = get_ur_golomb_jpegls(gb, k, limit, esc_len);
548 57934362 return (v >> 1) ^ -(v & 1);
549 }
550
551 /**
552 * read unsigned golomb rice code (shorten).
553 */
554 6320 static inline unsigned int get_ur_golomb_shorten(GetBitContext *gb, int k)
555 {
556 6320 return get_ur_golomb_jpegls(gb, k, INT_MAX, 0);
557 }
558
559 /**
560 * read signed golomb rice code (shorten).
561 */
562 793344 static inline int get_sr_golomb_shorten(GetBitContext *gb, int k)
563 {
564 793344 int uvar = get_ur_golomb_jpegls(gb, k + 1, INT_MAX, 0);
565 793344 return (uvar >> 1) ^ -(uvar & 1);
566 }
567
568 #ifdef TRACE
569
570 static inline int get_ue(GetBitContext *s, const char *file, const char *func,
571 int line)
572 {
573 int show = show_bits(s, 24);
574 int pos = get_bits_count(s);
575 int i = get_ue_golomb(s);
576 int len = get_bits_count(s) - pos;
577 int bits = show >> (24 - len);
578
579 av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d ue @%5d in %s %s:%d\n",
580 bits, len, i, pos, file, func, line);
581
582 return i;
583 }
584
585 static inline int get_se(GetBitContext *s, const char *file, const char *func,
586 int line)
587 {
588 int show = show_bits(s, 24);
589 int pos = get_bits_count(s);
590 int i = get_se_golomb(s);
591 int len = get_bits_count(s) - pos;
592 int bits = show >> (24 - len);
593
594 av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d se @%5d in %s %s:%d\n",
595 bits, len, i, pos, file, func, line);
596
597 return i;
598 }
599
600 static inline int get_te(GetBitContext *s, int r, char *file, const char *func,
601 int line)
602 {
603 int show = show_bits(s, 24);
604 int pos = get_bits_count(s);
605 int i = get_te0_golomb(s, r);
606 int len = get_bits_count(s) - pos;
607 int bits = show >> (24 - len);
608
609 av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d te @%5d in %s %s:%d\n",
610 bits, len, i, pos, file, func, line);
611
612 return i;
613 }
614
615 #define get_ue_golomb(a) get_ue(a, __FILE__, __func__, __LINE__)
616 #define get_se_golomb(a) get_se(a, __FILE__, __func__, __LINE__)
617 #define get_te_golomb(a, r) get_te(a, r, __FILE__, __func__, __LINE__)
618 #define get_te0_golomb(a, r) get_te(a, r, __FILE__, __func__, __LINE__)
619
620 #endif /* TRACE */
621 #endif /* AVCODEC_GOLOMB_H */
622