FFmpeg
common.h
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1 /*
2  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * common internal and external API header
24  */
25 
26 #ifndef AVUTIL_COMMON_H
27 #define AVUTIL_COMMON_H
28 
29 #if defined(__cplusplus) && !defined(__STDC_CONSTANT_MACROS) && !defined(UINT64_C)
30 #error missing -D__STDC_CONSTANT_MACROS / #define __STDC_CONSTANT_MACROS
31 #endif
32 
33 #include <errno.h>
34 #include <inttypes.h>
35 #include <limits.h>
36 #include <math.h>
37 #include <stdint.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 
42 #include "attributes.h"
43 #include "macros.h"
44 #include "version.h"
45 #include "libavutil/avconfig.h"
46 
47 #if AV_HAVE_BIGENDIAN
48 # define AV_NE(be, le) (be)
49 #else
50 # define AV_NE(be, le) (le)
51 #endif
52 
53 //rounded division & shift
54 #define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
55 /* assume b>0 */
56 #define ROUNDED_DIV(a,b) (((a)>=0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
57 /* Fast a/(1<<b) rounded toward +inf. Assume a>=0 and b>=0 */
58 #define AV_CEIL_RSHIFT(a,b) (!av_builtin_constant_p(b) ? -((-(a)) >> (b)) \
59  : ((a) + (1<<(b)) - 1) >> (b))
60 /* Backwards compat. */
61 #define FF_CEIL_RSHIFT AV_CEIL_RSHIFT
62 
63 #define FFUDIV(a,b) (((a)>0 ?(a):(a)-(b)+1) / (b))
64 #define FFUMOD(a,b) ((a)-(b)*FFUDIV(a,b))
65 
66 /**
67  * Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they
68  * are not representable as absolute values of their type. This is the same
69  * as with *abs()
70  * @see FFNABS()
71  */
72 #define FFABS(a) ((a) >= 0 ? (a) : (-(a)))
73 #define FFSIGN(a) ((a) > 0 ? 1 : -1)
74 
75 /**
76  * Negative Absolute value.
77  * this works for all integers of all types.
78  * As with many macros, this evaluates its argument twice, it thus must not have
79  * a sideeffect, that is FFNABS(x++) has undefined behavior.
80  */
81 #define FFNABS(a) ((a) <= 0 ? (a) : (-(a)))
82 
83 /**
84  * Comparator.
85  * For two numerical expressions x and y, gives 1 if x > y, -1 if x < y, and 0
86  * if x == y. This is useful for instance in a qsort comparator callback.
87  * Furthermore, compilers are able to optimize this to branchless code, and
88  * there is no risk of overflow with signed types.
89  * As with many macros, this evaluates its argument multiple times, it thus
90  * must not have a side-effect.
91  */
92 #define FFDIFFSIGN(x,y) (((x)>(y)) - ((x)<(y)))
93 
94 #define FFMAX(a,b) ((a) > (b) ? (a) : (b))
95 #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c)
96 #define FFMIN(a,b) ((a) > (b) ? (b) : (a))
97 #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c)
98 
99 #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
100 #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))
101 
102 /* misc math functions */
103 
104 #ifdef HAVE_AV_CONFIG_H
105 # include "config.h"
106 # include "intmath.h"
107 #endif
108 
109 /* Pull in unguarded fallback defines at the end of this file. */
110 #include "common.h"
111 
112 #ifndef av_log2
113 av_const int av_log2(unsigned v);
114 #endif
115 
116 #ifndef av_log2_16bit
117 av_const int av_log2_16bit(unsigned v);
118 #endif
119 
120 /**
121  * Clip a signed integer value into the amin-amax range.
122  * @param a value to clip
123  * @param amin minimum value of the clip range
124  * @param amax maximum value of the clip range
125  * @return clipped value
126  */
127 static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
128 {
129 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
130  if (amin > amax) abort();
131 #endif
132  if (a < amin) return amin;
133  else if (a > amax) return amax;
134  else return a;
135 }
136 
137 /**
138  * Clip a signed 64bit integer value into the amin-amax range.
139  * @param a value to clip
140  * @param amin minimum value of the clip range
141  * @param amax maximum value of the clip range
142  * @return clipped value
143  */
144 static av_always_inline av_const int64_t av_clip64_c(int64_t a, int64_t amin, int64_t amax)
145 {
146 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
147  if (amin > amax) abort();
148 #endif
149  if (a < amin) return amin;
150  else if (a > amax) return amax;
151  else return a;
152 }
153 
154 /**
155  * Clip a signed integer value into the 0-255 range.
156  * @param a value to clip
157  * @return clipped value
158  */
160 {
161  if (a&(~0xFF)) return (~a)>>31;
162  else return a;
163 }
164 
165 /**
166  * Clip a signed integer value into the -128,127 range.
167  * @param a value to clip
168  * @return clipped value
169  */
171 {
172  if ((a+0x80U) & ~0xFF) return (a>>31) ^ 0x7F;
173  else return a;
174 }
175 
176 /**
177  * Clip a signed integer value into the 0-65535 range.
178  * @param a value to clip
179  * @return clipped value
180  */
182 {
183  if (a&(~0xFFFF)) return (~a)>>31;
184  else return a;
185 }
186 
187 /**
188  * Clip a signed integer value into the -32768,32767 range.
189  * @param a value to clip
190  * @return clipped value
191  */
193 {
194  if ((a+0x8000U) & ~0xFFFF) return (a>>31) ^ 0x7FFF;
195  else return a;
196 }
197 
198 /**
199  * Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
200  * @param a value to clip
201  * @return clipped value
202  */
204 {
205  if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (int32_t)((a>>63) ^ 0x7FFFFFFF);
206  else return (int32_t)a;
207 }
208 
209 /**
210  * Clip a signed integer into the -(2^p),(2^p-1) range.
211  * @param a value to clip
212  * @param p bit position to clip at
213  * @return clipped value
214  */
216 {
217  if (((unsigned)a + (1 << p)) & ~((2 << p) - 1))
218  return (a >> 31) ^ ((1 << p) - 1);
219  else
220  return a;
221 }
222 
223 /**
224  * Clip a signed integer to an unsigned power of two range.
225  * @param a value to clip
226  * @param p bit position to clip at
227  * @return clipped value
228  */
229 static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
230 {
231  if (a & ~((1<<p) - 1)) return (~a) >> 31 & ((1<<p) - 1);
232  else return a;
233 }
234 
235 /**
236  * Clear high bits from an unsigned integer starting with specific bit position
237  * @param a value to clip
238  * @param p bit position to clip at
239  * @return clipped value
240  */
241 static av_always_inline av_const unsigned av_mod_uintp2_c(unsigned a, unsigned p)
242 {
243  return a & ((1U << p) - 1);
244 }
245 
246 /**
247  * Add two signed 32-bit values with saturation.
248  *
249  * @param a one value
250  * @param b another value
251  * @return sum with signed saturation
252  */
253 static av_always_inline int av_sat_add32_c(int a, int b)
254 {
255  return av_clipl_int32((int64_t)a + b);
256 }
257 
258 /**
259  * Add a doubled value to another value with saturation at both stages.
260  *
261  * @param a first value
262  * @param b value doubled and added to a
263  * @return sum sat(a + sat(2*b)) with signed saturation
264  */
265 static av_always_inline int av_sat_dadd32_c(int a, int b)
266 {
267  return av_sat_add32(a, av_sat_add32(b, b));
268 }
269 
270 /**
271  * Subtract two signed 32-bit values with saturation.
272  *
273  * @param a one value
274  * @param b another value
275  * @return difference with signed saturation
276  */
277 static av_always_inline int av_sat_sub32_c(int a, int b)
278 {
279  return av_clipl_int32((int64_t)a - b);
280 }
281 
282 /**
283  * Subtract a doubled value from another value with saturation at both stages.
284  *
285  * @param a first value
286  * @param b value doubled and subtracted from a
287  * @return difference sat(a - sat(2*b)) with signed saturation
288  */
289 static av_always_inline int av_sat_dsub32_c(int a, int b)
290 {
291  return av_sat_sub32(a, av_sat_add32(b, b));
292 }
293 
294 /**
295  * Add two signed 64-bit values with saturation.
296  *
297  * @param a one value
298  * @param b another value
299  * @return sum with signed saturation
300  */
301 static av_always_inline int64_t av_sat_add64_c(int64_t a, int64_t b) {
302  if (b >= 0 && a >= INT64_MAX - b)
303  return INT64_MAX;
304  if (b <= 0 && a <= INT64_MIN - b)
305  return INT64_MIN;
306  return a + b;
307 }
308 
309 /**
310  * Subtract two signed 64-bit values with saturation.
311  *
312  * @param a one value
313  * @param b another value
314  * @return difference with signed saturation
315  */
316 static av_always_inline int64_t av_sat_sub64_c(int64_t a, int64_t b) {
317  if (b <= 0 && a >= INT64_MAX + b)
318  return INT64_MAX;
319  if (b >= 0 && a <= INT64_MIN + b)
320  return INT64_MIN;
321  return a - b;
322 }
323 
324 /**
325  * Clip a float value into the amin-amax range.
326  * @param a value to clip
327  * @param amin minimum value of the clip range
328  * @param amax maximum value of the clip range
329  * @return clipped value
330  */
331 static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
332 {
333 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
334  if (amin > amax) abort();
335 #endif
336  if (a < amin) return amin;
337  else if (a > amax) return amax;
338  else return a;
339 }
340 
341 /**
342  * Clip a double value into the amin-amax range.
343  * @param a value to clip
344  * @param amin minimum value of the clip range
345  * @param amax maximum value of the clip range
346  * @return clipped value
347  */
348 static av_always_inline av_const double av_clipd_c(double a, double amin, double amax)
349 {
350 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
351  if (amin > amax) abort();
352 #endif
353  if (a < amin) return amin;
354  else if (a > amax) return amax;
355  else return a;
356 }
357 
358 /** Compute ceil(log2(x)).
359  * @param x value used to compute ceil(log2(x))
360  * @return computed ceiling of log2(x)
361  */
363 {
364  return av_log2((x - 1) << 1);
365 }
366 
367 /**
368  * Count number of bits set to one in x
369  * @param x value to count bits of
370  * @return the number of bits set to one in x
371  */
373 {
374  x -= (x >> 1) & 0x55555555;
375  x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
376  x = (x + (x >> 4)) & 0x0F0F0F0F;
377  x += x >> 8;
378  return (x + (x >> 16)) & 0x3F;
379 }
380 
381 /**
382  * Count number of bits set to one in x
383  * @param x value to count bits of
384  * @return the number of bits set to one in x
385  */
387 {
388  return av_popcount((uint32_t)x) + av_popcount((uint32_t)(x >> 32));
389 }
390 
391 static av_always_inline av_const int av_parity_c(uint32_t v)
392 {
393  return av_popcount(v) & 1;
394 }
395 
396 #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))
397 #define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24))
398 
399 /**
400  * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form.
401  *
402  * @param val Output value, must be an lvalue of type uint32_t.
403  * @param GET_BYTE Expression reading one byte from the input.
404  * Evaluated up to 7 times (4 for the currently
405  * assigned Unicode range). With a memory buffer
406  * input, this could be *ptr++, or if you want to make sure
407  * that *ptr stops at the end of a NULL terminated string then
408  * *ptr ? *ptr++ : 0
409  * @param ERROR Expression to be evaluated on invalid input,
410  * typically a goto statement.
411  *
412  * @warning ERROR should not contain a loop control statement which
413  * could interact with the internal while loop, and should force an
414  * exit from the macro code (e.g. through a goto or a return) in order
415  * to prevent undefined results.
416  */
417 #define GET_UTF8(val, GET_BYTE, ERROR)\
418  val= (GET_BYTE);\
419  {\
420  uint32_t top = (val & 128) >> 1;\
421  if ((val & 0xc0) == 0x80 || val >= 0xFE)\
422  {ERROR}\
423  while (val & top) {\
424  unsigned int tmp = (GET_BYTE) - 128;\
425  if(tmp>>6)\
426  {ERROR}\
427  val= (val<<6) + tmp;\
428  top <<= 5;\
429  }\
430  val &= (top << 1) - 1;\
431  }
432 
433 /**
434  * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form.
435  *
436  * @param val Output value, must be an lvalue of type uint32_t.
437  * @param GET_16BIT Expression returning two bytes of UTF-16 data converted
438  * to native byte order. Evaluated one or two times.
439  * @param ERROR Expression to be evaluated on invalid input,
440  * typically a goto statement.
441  */
442 #define GET_UTF16(val, GET_16BIT, ERROR)\
443  val = (GET_16BIT);\
444  {\
445  unsigned int hi = val - 0xD800;\
446  if (hi < 0x800) {\
447  val = (GET_16BIT) - 0xDC00;\
448  if (val > 0x3FFU || hi > 0x3FFU)\
449  {ERROR}\
450  val += (hi<<10) + 0x10000;\
451  }\
452  }\
453 
454 /**
455  * @def PUT_UTF8(val, tmp, PUT_BYTE)
456  * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).
457  * @param val is an input-only argument and should be of type uint32_t. It holds
458  * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If
459  * val is given as a function it is executed only once.
460  * @param tmp is a temporary variable and should be of type uint8_t. It
461  * represents an intermediate value during conversion that is to be
462  * output by PUT_BYTE.
463  * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
464  * It could be a function or a statement, and uses tmp as the input byte.
465  * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
466  * executed up to 4 times for values in the valid UTF-8 range and up to
467  * 7 times in the general case, depending on the length of the converted
468  * Unicode character.
469  */
470 #define PUT_UTF8(val, tmp, PUT_BYTE)\
471  {\
472  int bytes, shift;\
473  uint32_t in = val;\
474  if (in < 0x80) {\
475  tmp = in;\
476  PUT_BYTE\
477  } else {\
478  bytes = (av_log2(in) + 4) / 5;\
479  shift = (bytes - 1) * 6;\
480  tmp = (256 - (256 >> bytes)) | (in >> shift);\
481  PUT_BYTE\
482  while (shift >= 6) {\
483  shift -= 6;\
484  tmp = 0x80 | ((in >> shift) & 0x3f);\
485  PUT_BYTE\
486  }\
487  }\
488  }
489 
490 /**
491  * @def PUT_UTF16(val, tmp, PUT_16BIT)
492  * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes).
493  * @param val is an input-only argument and should be of type uint32_t. It holds
494  * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If
495  * val is given as a function it is executed only once.
496  * @param tmp is a temporary variable and should be of type uint16_t. It
497  * represents an intermediate value during conversion that is to be
498  * output by PUT_16BIT.
499  * @param PUT_16BIT writes the converted UTF-16 data to any proper destination
500  * in desired endianness. It could be a function or a statement, and uses tmp
501  * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;"
502  * PUT_BYTE will be executed 1 or 2 times depending on input character.
503  */
504 #define PUT_UTF16(val, tmp, PUT_16BIT)\
505  {\
506  uint32_t in = val;\
507  if (in < 0x10000) {\
508  tmp = in;\
509  PUT_16BIT\
510  } else {\
511  tmp = 0xD800 | ((in - 0x10000) >> 10);\
512  PUT_16BIT\
513  tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\
514  PUT_16BIT\
515  }\
516  }\
517 
518 
519 
520 #include "mem.h"
521 
522 #ifdef HAVE_AV_CONFIG_H
523 # include "internal.h"
524 #endif /* HAVE_AV_CONFIG_H */
525 
526 #endif /* AVUTIL_COMMON_H */
527 
528 /*
529  * The following definitions are outside the multiple inclusion guard
530  * to ensure they are immediately available in intmath.h.
531  */
532 
533 #ifndef av_ceil_log2
534 # define av_ceil_log2 av_ceil_log2_c
535 #endif
536 #ifndef av_clip
537 # define av_clip av_clip_c
538 #endif
539 #ifndef av_clip64
540 # define av_clip64 av_clip64_c
541 #endif
542 #ifndef av_clip_uint8
543 # define av_clip_uint8 av_clip_uint8_c
544 #endif
545 #ifndef av_clip_int8
546 # define av_clip_int8 av_clip_int8_c
547 #endif
548 #ifndef av_clip_uint16
549 # define av_clip_uint16 av_clip_uint16_c
550 #endif
551 #ifndef av_clip_int16
552 # define av_clip_int16 av_clip_int16_c
553 #endif
554 #ifndef av_clipl_int32
555 # define av_clipl_int32 av_clipl_int32_c
556 #endif
557 #ifndef av_clip_intp2
558 # define av_clip_intp2 av_clip_intp2_c
559 #endif
560 #ifndef av_clip_uintp2
561 # define av_clip_uintp2 av_clip_uintp2_c
562 #endif
563 #ifndef av_mod_uintp2
564 # define av_mod_uintp2 av_mod_uintp2_c
565 #endif
566 #ifndef av_sat_add32
567 # define av_sat_add32 av_sat_add32_c
568 #endif
569 #ifndef av_sat_dadd32
570 # define av_sat_dadd32 av_sat_dadd32_c
571 #endif
572 #ifndef av_sat_sub32
573 # define av_sat_sub32 av_sat_sub32_c
574 #endif
575 #ifndef av_sat_dsub32
576 # define av_sat_dsub32 av_sat_dsub32_c
577 #endif
578 #ifndef av_sat_add64
579 # define av_sat_add64 av_sat_add64_c
580 #endif
581 #ifndef av_sat_sub64
582 # define av_sat_sub64 av_sat_sub64_c
583 #endif
584 #ifndef av_clipf
585 # define av_clipf av_clipf_c
586 #endif
587 #ifndef av_clipd
588 # define av_clipd av_clipd_c
589 #endif
590 #ifndef av_popcount
591 # define av_popcount av_popcount_c
592 #endif
593 #ifndef av_popcount64
594 # define av_popcount64 av_popcount64_c
595 #endif
596 #ifndef av_parity
597 # define av_parity av_parity_c
598 #endif
#define av_const
Definition: attributes.h:76
static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a)
Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
Definition: common.h:203
static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
Clip a float value into the amin-amax range.
Definition: common.h:331
static av_always_inline av_const unsigned av_mod_uintp2_c(unsigned a, unsigned p)
Clear high bits from an unsigned integer starting with specific bit position.
Definition: common.h:241
Memory handling functions.
static av_always_inline int av_sat_sub32_c(int a, int b)
Subtract two signed 32-bit values with saturation.
Definition: common.h:277
int av_log2(unsigned v)
Definition: intmath.c:26
static av_always_inline av_const int8_t av_clip_int8_c(int a)
Clip a signed integer value into the -128,127 range.
Definition: common.h:170
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:36
int av_log2_16bit(unsigned v)
Definition: intmath.c:31
Macro definitions for various function/variable attributes.
static av_always_inline int64_t av_sat_add64_c(int64_t a, int64_t b)
Add two signed 64-bit values with saturation.
Definition: common.h:301
uint8_t
static av_always_inline int64_t av_sat_sub64_c(int64_t a, int64_t b)
Subtract two signed 64-bit values with saturation.
Definition: common.h:316
static av_always_inline int av_sat_dsub32_c(int a, int b)
Subtract a doubled value from another value with saturation at both stages.
Definition: common.h:289
Utility Preprocessor macros.
#define U(x)
Definition: vp56_arith.h:37
static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
Clip a signed integer value into the amin-amax range.
Definition: common.h:127
Libavutil version macros.
static av_always_inline av_const uint16_t av_clip_uint16_c(int a)
Clip a signed integer value into the 0-65535 range.
Definition: common.h:181
static av_always_inline av_const uint8_t av_clip_uint8_c(int a)
Clip a signed integer value into the 0-255 range.
Definition: common.h:159
common internal API header
#define b
Definition: input.c:41
int32_t
static av_always_inline av_const double av_clipd_c(double a, double amin, double amax)
Clip a double value into the amin-amax range.
Definition: common.h:348
static av_always_inline av_const int av_clip_intp2_c(int a, int p)
Clip a signed integer into the -(2^p),(2^p-1) range.
Definition: common.h:215
static av_always_inline av_const int16_t av_clip_int16_c(int a)
Clip a signed integer value into the -32768,32767 range.
Definition: common.h:192
common internal and external API header
static av_always_inline av_const int av_popcount_c(uint32_t x)
Count number of bits set to one in x.
Definition: common.h:372
static av_always_inline int av_sat_add32_c(int a, int b)
Add two signed 32-bit values with saturation.
Definition: common.h:253
static av_always_inline av_const int av_popcount64_c(uint64_t x)
Count number of bits set to one in x.
Definition: common.h:386
static av_always_inline av_const int av_parity_c(uint32_t v)
Definition: common.h:391
static av_always_inline int av_sat_dadd32_c(int a, int b)
Add a doubled value to another value with saturation at both stages.
Definition: common.h:265
#define av_always_inline
Definition: attributes.h:39
static av_always_inline av_const int av_ceil_log2_c(int x)
Compute ceil(log2(x)).
Definition: common.h:362
static av_always_inline av_const int64_t av_clip64_c(int64_t a, int64_t amin, int64_t amax)
Clip a signed 64bit integer value into the amin-amax range.
Definition: common.h:144
static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
Clip a signed integer to an unsigned power of two range.
Definition: common.h:229