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golomb.h
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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 #include "put_bits.h"
37 
38 #define INVALID_VLC 0x80000000
39 
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];
44 
45 extern const uint8_t ff_interleaved_golomb_vlc_len[256];
47 extern const int8_t ff_interleaved_se_golomb_vlc_code[256];
49 
50 /**
51  * Read an unsigned Exp-Golomb code in the range 0 to 8190.
52  */
53 static inline int get_ue_golomb(GetBitContext *gb)
54 {
55  unsigned int buf;
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;
64  CLOSE_READER(re, gb);
65 
66  return ff_ue_golomb_vlc_code[buf];
67  } else {
68  int log = 2 * av_log2(buf) - 31;
69  LAST_SKIP_BITS(re, gb, 32 - log);
70  CLOSE_READER(re, gb);
71  if (log < 7) {
72  av_log(NULL, AV_LOG_ERROR, "Invalid UE golomb code\n");
73  return AVERROR_INVALIDDATA;
74  }
75  buf >>= log;
76  buf--;
77 
78  return buf;
79  }
80 }
81 
82 /**
83  * Read an unsigned Exp-Golomb code in the range 0 to UINT32_MAX-1.
84  */
85 static inline unsigned get_ue_golomb_long(GetBitContext *gb)
86 {
87  unsigned buf, log;
88 
89  buf = show_bits_long(gb, 32);
90  log = 31 - av_log2(buf);
91  skip_bits_long(gb, log);
92 
93  return get_bits_long(gb, log + 1) - 1;
94 }
95 
96 /**
97  * read unsigned exp golomb code, constraint to a max of 31.
98  * the return value is undefined if the stored value exceeds 31.
99  */
100 static inline int get_ue_golomb_31(GetBitContext *gb)
101 {
102  unsigned int buf;
103 
104  OPEN_READER(re, gb);
105  UPDATE_CACHE(re, gb);
106  buf = GET_CACHE(re, gb);
107 
108  buf >>= 32 - 9;
110  CLOSE_READER(re, gb);
111 
112  return ff_ue_golomb_vlc_code[buf];
113 }
114 
115 static inline unsigned get_interleaved_ue_golomb(GetBitContext *gb)
116 {
117  uint32_t buf;
118 
119  OPEN_READER(re, gb);
120  UPDATE_CACHE(re, gb);
121  buf = GET_CACHE(re, gb);
122 
123  if (buf & 0xAA800000) {
124  buf >>= 32 - 8;
126  CLOSE_READER(re, gb);
127 
129  } else {
130  unsigned ret = 1;
131 
132  do {
133  buf >>= 32 - 8;
134  LAST_SKIP_BITS(re, gb,
136 
137  if (ff_interleaved_golomb_vlc_len[buf] != 9) {
138  ret <<= (ff_interleaved_golomb_vlc_len[buf] - 1) >> 1;
140  break;
141  }
142  ret = (ret << 4) | ff_interleaved_dirac_golomb_vlc_code[buf];
143  UPDATE_CACHE(re, gb);
144  buf = GET_CACHE(re, gb);
145  } while (ret<0x8000000U && BITS_AVAILABLE(re, gb));
146 
147  CLOSE_READER(re, gb);
148  return ret - 1;
149  }
150 }
151 
152 /**
153  * read unsigned truncated exp golomb code.
154  */
155 static inline int get_te0_golomb(GetBitContext *gb, int range)
156 {
157  av_assert2(range >= 1);
158 
159  if (range == 1)
160  return 0;
161  else if (range == 2)
162  return get_bits1(gb) ^ 1;
163  else
164  return get_ue_golomb(gb);
165 }
166 
167 /**
168  * read unsigned truncated exp golomb code.
169  */
170 static inline int get_te_golomb(GetBitContext *gb, int range)
171 {
172  av_assert2(range >= 1);
173 
174  if (range == 2)
175  return get_bits1(gb) ^ 1;
176  else
177  return get_ue_golomb(gb);
178 }
179 
180 /**
181  * read signed exp golomb code.
182  */
183 static inline int get_se_golomb(GetBitContext *gb)
184 {
185  unsigned int buf;
186 
187  OPEN_READER(re, gb);
188  UPDATE_CACHE(re, gb);
189  buf = GET_CACHE(re, gb);
190 
191  if (buf >= (1 << 27)) {
192  buf >>= 32 - 9;
194  CLOSE_READER(re, gb);
195 
196  return ff_se_golomb_vlc_code[buf];
197  } else {
198  int log = av_log2(buf), sign;
199  LAST_SKIP_BITS(re, gb, 31 - log);
200  UPDATE_CACHE(re, gb);
201  buf = GET_CACHE(re, gb);
202 
203  buf >>= log;
204 
205  LAST_SKIP_BITS(re, gb, 32 - log);
206  CLOSE_READER(re, gb);
207 
208  sign = -(buf & 1);
209  buf = ((buf >> 1) ^ sign) - sign;
210 
211  return buf;
212  }
213 }
214 
215 static inline int get_se_golomb_long(GetBitContext *gb)
216 {
217  unsigned int buf = get_ue_golomb_long(gb);
218  int sign = (buf & 1) - 1;
219  return ((buf >> 1) ^ sign) + 1;
220 }
221 
223 {
224  unsigned int buf;
225 
226  OPEN_READER(re, gb);
227  UPDATE_CACHE(re, gb);
228  buf = GET_CACHE(re, gb);
229 
230  if (buf & 0xAA800000) {
231  buf >>= 32 - 8;
233  CLOSE_READER(re, gb);
234 
236  } else {
237  int log;
238  LAST_SKIP_BITS(re, gb, 8);
239  UPDATE_CACHE(re, gb);
240  buf |= 1 | (GET_CACHE(re, gb) >> 8);
241 
242  if ((buf & 0xAAAAAAAA) == 0)
243  return INVALID_VLC;
244 
245  for (log = 31; (buf & 0x80000000) == 0; log--)
246  buf = (buf << 2) - ((buf << log) >> (log - 1)) + (buf >> 30);
247 
248  LAST_SKIP_BITS(re, gb, 63 - 2 * log - 8);
249  CLOSE_READER(re, gb);
250 
251  return (signed) (((((buf << log) >> log) - 1) ^ -(buf & 0x1)) + 1) >> 1;
252  }
253 }
254 
255 static inline int dirac_get_se_golomb(GetBitContext *gb)
256 {
257  uint32_t ret = get_interleaved_ue_golomb(gb);
258 
259  if (ret) {
260  int sign = -get_bits1(gb);
261  ret = (ret ^ sign) - sign;
262  }
263 
264  return ret;
265 }
266 
267 /**
268  * read unsigned golomb rice code (ffv1).
269  */
270 static inline int get_ur_golomb(GetBitContext *gb, int k, int limit,
271  int esc_len)
272 {
273  unsigned int buf;
274  int log;
275 
276  OPEN_READER(re, gb);
277  UPDATE_CACHE(re, gb);
278  buf = GET_CACHE(re, gb);
279 
280  log = av_log2(buf);
281 
282  if (log > 31 - limit) {
283  buf >>= log - k;
284  buf += (30U - log) << k;
285  LAST_SKIP_BITS(re, gb, 32 + k - log);
286  CLOSE_READER(re, gb);
287 
288  return buf;
289  } else {
290  LAST_SKIP_BITS(re, gb, limit);
291  UPDATE_CACHE(re, gb);
292 
293  buf = SHOW_UBITS(re, gb, esc_len);
294 
295  LAST_SKIP_BITS(re, gb, esc_len);
296  CLOSE_READER(re, gb);
297 
298  return buf + limit - 1;
299  }
300 }
301 
302 /**
303  * read unsigned golomb rice code (jpegls).
304  */
305 static inline int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit,
306  int esc_len)
307 {
308  unsigned int buf;
309  int log;
310 
311  OPEN_READER(re, gb);
312  UPDATE_CACHE(re, gb);
313  buf = GET_CACHE(re, gb);
314 
315  log = av_log2(buf);
316 
317  if (log - k >= 32 - MIN_CACHE_BITS + (MIN_CACHE_BITS == 32) &&
318  32 - log < limit) {
319  buf >>= log - k;
320  buf += (30U - log) << k;
321  LAST_SKIP_BITS(re, gb, 32 + k - log);
322  CLOSE_READER(re, gb);
323 
324  return buf;
325  } else {
326  int i;
327  for (i = 0; i < limit && SHOW_UBITS(re, gb, 1) == 0; i++) {
328  if (gb->size_in_bits <= re_index)
329  return -1;
330  LAST_SKIP_BITS(re, gb, 1);
331  UPDATE_CACHE(re, gb);
332  }
333  SKIP_BITS(re, gb, 1);
334 
335  if (i < limit - 1) {
336  if (k) {
337  if (k > MIN_CACHE_BITS - 1) {
338  buf = SHOW_UBITS(re, gb, 16) << (k-16);
339  LAST_SKIP_BITS(re, gb, 16);
340  UPDATE_CACHE(re, gb);
341  buf |= SHOW_UBITS(re, gb, k-16);
342  LAST_SKIP_BITS(re, gb, k-16);
343  } else {
344  buf = SHOW_UBITS(re, gb, k);
345  LAST_SKIP_BITS(re, gb, k);
346  }
347  } else {
348  buf = 0;
349  }
350 
351  CLOSE_READER(re, gb);
352  return buf + (i << k);
353  } else if (i == limit - 1) {
354  buf = SHOW_UBITS(re, gb, esc_len);
355  LAST_SKIP_BITS(re, gb, esc_len);
356  CLOSE_READER(re, gb);
357 
358  return buf + 1;
359  } else
360  return -1;
361  }
362 }
363 
364 /**
365  * read signed golomb rice code (ffv1).
366  */
367 static inline int get_sr_golomb(GetBitContext *gb, int k, int limit,
368  int esc_len)
369 {
370  unsigned v = get_ur_golomb(gb, k, limit, esc_len);
371  return (v >> 1) ^ -(v & 1);
372 }
373 
374 /**
375  * read signed golomb rice code (flac).
376  */
377 static inline int get_sr_golomb_flac(GetBitContext *gb, int k, int limit,
378  int esc_len)
379 {
380  unsigned v = get_ur_golomb_jpegls(gb, k, limit, esc_len);
381  return (v >> 1) ^ -(v & 1);
382 }
383 
384 /**
385  * read unsigned golomb rice code (shorten).
386  */
387 static inline unsigned int get_ur_golomb_shorten(GetBitContext *gb, int k)
388 {
389  return get_ur_golomb_jpegls(gb, k, INT_MAX, 0);
390 }
391 
392 /**
393  * read signed golomb rice code (shorten).
394  */
395 static inline int get_sr_golomb_shorten(GetBitContext *gb, int k)
396 {
397  int uvar = get_ur_golomb_jpegls(gb, k + 1, INT_MAX, 0);
398  return (uvar >> 1) ^ -(uvar & 1);
399 }
400 
401 #ifdef TRACE
402 
403 static inline int get_ue(GetBitContext *s, const char *file, const char *func,
404  int line)
405 {
406  int show = show_bits(s, 24);
407  int pos = get_bits_count(s);
408  int i = get_ue_golomb(s);
409  int len = get_bits_count(s) - pos;
410  int bits = show >> (24 - len);
411 
412  av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d ue @%5d in %s %s:%d\n",
413  bits, len, i, pos, file, func, line);
414 
415  return i;
416 }
417 
418 static inline int get_se(GetBitContext *s, const char *file, const char *func,
419  int line)
420 {
421  int show = show_bits(s, 24);
422  int pos = get_bits_count(s);
423  int i = get_se_golomb(s);
424  int len = get_bits_count(s) - pos;
425  int bits = show >> (24 - len);
426 
427  av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d se @%5d in %s %s:%d\n",
428  bits, len, i, pos, file, func, line);
429 
430  return i;
431 }
432 
433 static inline int get_te(GetBitContext *s, int r, char *file, const char *func,
434  int line)
435 {
436  int show = show_bits(s, 24);
437  int pos = get_bits_count(s);
438  int i = get_te0_golomb(s, r);
439  int len = get_bits_count(s) - pos;
440  int bits = show >> (24 - len);
441 
442  av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d te @%5d in %s %s:%d\n",
443  bits, len, i, pos, file, func, line);
444 
445  return i;
446 }
447 
448 #define get_ue_golomb(a) get_ue(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
449 #define get_se_golomb(a) get_se(a, __FILE__, __PRETTY_FUNCTION__, __LINE__)
450 #define get_te_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
451 #define get_te0_golomb(a, r) get_te(a, r, __FILE__, __PRETTY_FUNCTION__, __LINE__)
452 
453 #endif /* TRACE */
454 
455 /**
456  * write unsigned exp golomb code.
457  */
458 static inline void set_ue_golomb(PutBitContext *pb, int i)
459 {
460  av_assert2(i >= 0);
461 
462  if (i < 256)
463  put_bits(pb, ff_ue_golomb_len[i], i + 1);
464  else {
465  int e = av_log2(i + 1);
466  put_bits(pb, 2 * e + 1, i + 1);
467  }
468 }
469 
470 /**
471  * write truncated unsigned exp golomb code.
472  */
473 static inline void set_te_golomb(PutBitContext *pb, int i, int range)
474 {
475  av_assert2(range >= 1);
476  av_assert2(i <= range);
477 
478  if (range == 2)
479  put_bits(pb, 1, i ^ 1);
480  else
481  set_ue_golomb(pb, i);
482 }
483 
484 /**
485  * write signed exp golomb code. 16 bits at most.
486  */
487 static inline void set_se_golomb(PutBitContext *pb, int i)
488 {
489 #if 0
490  if (i <= 0)
491  i = -2 * i;
492  else
493  i = 2 * i - 1;
494 #elif 1
495  i = 2 * i - 1;
496  if (i < 0)
497  i ^= -1; //FIXME check if gcc does the right thing
498 #else
499  i = 2 * i - 1;
500  i ^= (i >> 31);
501 #endif
502  set_ue_golomb(pb, i);
503 }
504 
505 /**
506  * write unsigned golomb rice code (ffv1).
507  */
508 static inline void set_ur_golomb(PutBitContext *pb, int i, int k, int limit,
509  int esc_len)
510 {
511  int e;
512 
513  av_assert2(i >= 0);
514 
515  e = i >> k;
516  if (e < limit)
517  put_bits(pb, e + k + 1, (1 << k) + av_mod_uintp2(i, k));
518  else
519  put_bits(pb, limit + esc_len, i - limit + 1);
520 }
521 
522 /**
523  * write unsigned golomb rice code (jpegls).
524  */
525 static inline void set_ur_golomb_jpegls(PutBitContext *pb, int i, int k,
526  int limit, int esc_len)
527 {
528  int e;
529 
530  av_assert2(i >= 0);
531 
532  e = (i >> k) + 1;
533  if (e < limit) {
534  while (e > 31) {
535  put_bits(pb, 31, 0);
536  e -= 31;
537  }
538  put_bits(pb, e, 1);
539  if (k)
540  put_sbits(pb, k, i);
541  } else {
542  while (limit > 31) {
543  put_bits(pb, 31, 0);
544  limit -= 31;
545  }
546  put_bits(pb, limit, 1);
547  put_bits(pb, esc_len, i - 1);
548  }
549 }
550 
551 /**
552  * write signed golomb rice code (ffv1).
553  */
554 static inline void set_sr_golomb(PutBitContext *pb, int i, int k, int limit,
555  int esc_len)
556 {
557  int v;
558 
559  v = -2 * i - 1;
560  v ^= (v >> 31);
561 
562  set_ur_golomb(pb, v, k, limit, esc_len);
563 }
564 
565 /**
566  * write signed golomb rice code (flac).
567  */
568 static inline void set_sr_golomb_flac(PutBitContext *pb, int i, int k,
569  int limit, int esc_len)
570 {
571  int v;
572 
573  v = -2 * i - 1;
574  v ^= (v >> 31);
575 
576  set_ur_golomb_jpegls(pb, v, k, limit, esc_len);
577 }
578 
579 #endif /* AVCODEC_GOLOMB_H */
static unsigned int show_bits_long(GetBitContext *s, int n)
Show 0-32 bits.
Definition: get_bits.h:378
static int get_sr_golomb_flac(GetBitContext *gb, int k, int limit, int esc_len)
read signed golomb rice code (flac).
Definition: golomb.h:377
static void set_ur_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len)
write unsigned golomb rice code (ffv1).
Definition: golomb.h:508
#define NULL
Definition: coverity.c:32
#define BITS_AVAILABLE(name, gb)
Definition: get_bits.h:122
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
static int get_se_golomb(GetBitContext *gb)
read signed exp golomb code.
Definition: golomb.h:183
const uint8_t ff_ue_golomb_vlc_code[512]
Definition: golomb.c:50
float re
Definition: fft.c:82
static void put_sbits(PutBitContext *pb, int n, int32_t value)
Definition: put_bits.h:200
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:206
static void skip_bits_long(GetBitContext *s, int n)
Definition: get_bits.h:204
static void set_ue_golomb(PutBitContext *pb, int i)
write unsigned exp golomb code.
Definition: golomb.h:458
const int8_t ff_interleaved_se_golomb_vlc_code[256]
Definition: golomb.c:138
const uint8_t ff_interleaved_golomb_vlc_len[256]
Definition: golomb.c:100
int av_log2(unsigned v)
Definition: intmath.c:26
#define INVALID_VLC
Definition: golomb.h:38
static int get_te0_golomb(GetBitContext *gb, int range)
read unsigned truncated exp golomb code.
Definition: golomb.h:155
static int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit, int esc_len)
read unsigned golomb rice code (jpegls).
Definition: golomb.h:305
const uint8_t ff_interleaved_dirac_golomb_vlc_code[256]
Definition: golomb.c:157
uint8_t bits
Definition: crc.c:296
uint8_t
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:63
static void set_te_golomb(PutBitContext *pb, int i, int range)
write truncated unsigned exp golomb code.
Definition: golomb.h:473
static int dirac_get_se_golomb(GetBitContext *gb)
Definition: golomb.h:255
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:199
bitstream reader API header.
const uint8_t ff_golomb_vlc_len[512]
Definition: golomb.c:31
static int get_ur_golomb(GetBitContext *gb, int k, int limit, int esc_len)
read unsigned golomb rice code (ffv1).
Definition: golomb.h:270
#define av_log(a,...)
#define U(x)
Definition: vp56_arith.h:37
#define UPDATE_CACHE(name, gb)
Definition: get_bits.h:160
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static int get_ue_golomb(GetBitContext *gb)
Read an unsigned Exp-Golomb code in the range 0 to 8190.
Definition: golomb.h:53
const char * r
Definition: vf_curves.c:111
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
Definition: graph2dot.c:48
static int get_interleaved_se_golomb(GetBitContext *gb)
Definition: golomb.h:222
const int8_t ff_se_golomb_vlc_code[512]
Definition: golomb.c:69
#define CLOSE_READER(name, gb)
Definition: get_bits.h:131
#define SKIP_BITS(name, gb, num)
Definition: get_bits.h:175
#define FFMIN(a, b)
Definition: common.h:96
int size_in_bits
Definition: get_bits.h:58
static unsigned int show_bits(GetBitContext *s, int n)
Show 1-25 bits.
Definition: get_bits.h:282
#define LAST_SKIP_BITS(name, gb, num)
Definition: get_bits.h:181
static void set_ur_golomb_jpegls(PutBitContext *pb, int i, int k, int limit, int esc_len)
write unsigned golomb rice code (jpegls).
Definition: golomb.h:525
#define SHOW_UBITS(name, gb, num)
Definition: get_bits.h:193
static void set_sr_golomb_flac(PutBitContext *pb, int i, int k, int limit, int esc_len)
write signed golomb rice code (flac).
Definition: golomb.h:568
static unsigned get_ue_golomb_long(GetBitContext *gb)
Read an unsigned Exp-Golomb code in the range 0 to UINT32_MAX-1.
Definition: golomb.h:85
static int get_se_golomb_long(GetBitContext *gb)
Definition: golomb.h:215
static void set_se_golomb(PutBitContext *pb, int i)
write signed exp golomb code.
Definition: golomb.h:487
static int get_ue_golomb_31(GetBitContext *gb)
read unsigned exp golomb code, constraint to a max of 31.
Definition: golomb.h:100
#define OPEN_READER(name, gb)
Definition: get_bits.h:120
void * buf
Definition: avisynth_c.h:690
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:299
const uint8_t ff_interleaved_ue_golomb_vlc_code[256]
Definition: golomb.c:119
static void set_sr_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len)
write signed golomb rice code (ffv1).
Definition: golomb.h:554
#define GET_CACHE(name, gb)
Definition: get_bits.h:197
int(* func)(AVBPrint *dst, const char *in, const char *arg)
Definition: jacosubdec.c:67
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:332
#define MIN_CACHE_BITS
Definition: get_bits.h:112
static int get_te_golomb(GetBitContext *gb, int range)
read unsigned truncated exp golomb code.
Definition: golomb.h:170
const uint8_t ff_ue_golomb_len[256]
Definition: golomb.c:89
int len
static unsigned get_interleaved_ue_golomb(GetBitContext *gb)
Definition: golomb.h:115
static unsigned int get_ur_golomb_shorten(GetBitContext *gb, int k)
read unsigned golomb rice code (shorten).
Definition: golomb.h:387
static int get_sr_golomb(GetBitContext *gb, int k, int limit, int esc_len)
read signed golomb rice code (ffv1).
Definition: golomb.h:367
static int get_sr_golomb_shorten(GetBitContext *gb, int k)
read signed golomb rice code (shorten).
Definition: golomb.h:395
bitstream writer API