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 "error.h"
44 #include "macros.h"
45 #include "mem.h"
46 
47 #ifdef HAVE_AV_CONFIG_H
48 # include "config.h"
49 # include "intmath.h"
50 # include "internal.h"
51 #endif /* HAVE_AV_CONFIG_H */
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  * Unsigned Absolute value.
85  * This takes the absolute value of a signed int and returns it as a unsigned.
86  * This also works with INT_MIN which would otherwise not be representable
87  * As with many macros, this evaluates its argument twice.
88  */
89 #define FFABSU(a) ((a) <= 0 ? -(unsigned)(a) : (unsigned)(a))
90 #define FFABS64U(a) ((a) <= 0 ? -(uint64_t)(a) : (uint64_t)(a))
91 
92 /* misc math functions */
93 
94 #ifndef av_ceil_log2
95 # define av_ceil_log2 av_ceil_log2_c
96 #endif
97 #ifndef av_clip
98 # define av_clip av_clip_c
99 #endif
100 #ifndef av_clip64
101 # define av_clip64 av_clip64_c
102 #endif
103 #ifndef av_clip_uint8
104 # define av_clip_uint8 av_clip_uint8_c
105 #endif
106 #ifndef av_clip_int8
107 # define av_clip_int8 av_clip_int8_c
108 #endif
109 #ifndef av_clip_uint16
110 # define av_clip_uint16 av_clip_uint16_c
111 #endif
112 #ifndef av_clip_int16
113 # define av_clip_int16 av_clip_int16_c
114 #endif
115 #ifndef av_clipl_int32
116 # define av_clipl_int32 av_clipl_int32_c
117 #endif
118 #ifndef av_clip_intp2
119 # define av_clip_intp2 av_clip_intp2_c
120 #endif
121 #ifndef av_clip_uintp2
122 # define av_clip_uintp2 av_clip_uintp2_c
123 #endif
124 #ifndef av_mod_uintp2
125 # define av_mod_uintp2 av_mod_uintp2_c
126 #endif
127 #ifndef av_sat_add32
128 # define av_sat_add32 av_sat_add32_c
129 #endif
130 #ifndef av_sat_dadd32
131 # define av_sat_dadd32 av_sat_dadd32_c
132 #endif
133 #ifndef av_sat_sub32
134 # define av_sat_sub32 av_sat_sub32_c
135 #endif
136 #ifndef av_sat_dsub32
137 # define av_sat_dsub32 av_sat_dsub32_c
138 #endif
139 #ifndef av_sat_add64
140 # define av_sat_add64 av_sat_add64_c
141 #endif
142 #ifndef av_sat_sub64
143 # define av_sat_sub64 av_sat_sub64_c
144 #endif
145 #ifndef av_clipf
146 # define av_clipf av_clipf_c
147 #endif
148 #ifndef av_clipd
149 # define av_clipd av_clipd_c
150 #endif
151 #ifndef av_popcount
152 # define av_popcount av_popcount_c
153 #endif
154 #ifndef av_popcount64
155 # define av_popcount64 av_popcount64_c
156 #endif
157 #ifndef av_parity
158 # define av_parity av_parity_c
159 #endif
160 
161 #ifndef av_log2
162 av_const int av_log2(unsigned v);
163 #endif
164 
165 #ifndef av_log2_16bit
166 av_const int av_log2_16bit(unsigned v);
167 #endif
168 
169 /**
170  * Clip a signed integer value into the amin-amax range.
171  * @param a value to clip
172  * @param amin minimum value of the clip range
173  * @param amax maximum value of the clip range
174  * @return clipped value
175  */
176 static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
177 {
178 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
179  if (amin > amax) abort();
180 #endif
181  if (a < amin) return amin;
182  else if (a > amax) return amax;
183  else return a;
184 }
185 
186 /**
187  * Clip a signed 64bit integer value into the amin-amax range.
188  * @param a value to clip
189  * @param amin minimum value of the clip range
190  * @param amax maximum value of the clip range
191  * @return clipped value
192  */
193 static av_always_inline av_const int64_t av_clip64_c(int64_t a, int64_t amin, int64_t amax)
194 {
195 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
196  if (amin > amax) abort();
197 #endif
198  if (a < amin) return amin;
199  else if (a > amax) return amax;
200  else return a;
201 }
202 
203 /**
204  * Clip a signed integer value into the 0-255 range.
205  * @param a value to clip
206  * @return clipped value
207  */
209 {
210  if (a&(~0xFF)) return (~a)>>31;
211  else return a;
212 }
213 
214 /**
215  * Clip a signed integer value into the -128,127 range.
216  * @param a value to clip
217  * @return clipped value
218  */
220 {
221  if ((a+0x80U) & ~0xFF) return (a>>31) ^ 0x7F;
222  else return a;
223 }
224 
225 /**
226  * Clip a signed integer value into the 0-65535 range.
227  * @param a value to clip
228  * @return clipped value
229  */
231 {
232  if (a&(~0xFFFF)) return (~a)>>31;
233  else return a;
234 }
235 
236 /**
237  * Clip a signed integer value into the -32768,32767 range.
238  * @param a value to clip
239  * @return clipped value
240  */
242 {
243  if ((a+0x8000U) & ~0xFFFF) return (a>>31) ^ 0x7FFF;
244  else return a;
245 }
246 
247 /**
248  * Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
249  * @param a value to clip
250  * @return clipped value
251  */
253 {
254  if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (int32_t)((a>>63) ^ 0x7FFFFFFF);
255  else return (int32_t)a;
256 }
257 
258 /**
259  * Clip a signed integer into the -(2^p),(2^p-1) range.
260  * @param a value to clip
261  * @param p bit position to clip at
262  * @return clipped value
263  */
265 {
266  if (((unsigned)a + (1 << p)) & ~((2 << p) - 1))
267  return (a >> 31) ^ ((1 << p) - 1);
268  else
269  return a;
270 }
271 
272 /**
273  * Clip a signed integer to an unsigned power of two range.
274  * @param a value to clip
275  * @param p bit position to clip at
276  * @return clipped value
277  */
278 static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
279 {
280  if (a & ~((1<<p) - 1)) return (~a) >> 31 & ((1<<p) - 1);
281  else return a;
282 }
283 
284 /**
285  * Clear high bits from an unsigned integer starting with specific bit position
286  * @param a value to clip
287  * @param p bit position to clip at
288  * @return clipped value
289  */
290 static av_always_inline av_const unsigned av_mod_uintp2_c(unsigned a, unsigned p)
291 {
292  return a & ((1U << p) - 1);
293 }
294 
295 /**
296  * Add two signed 32-bit values with saturation.
297  *
298  * @param a one value
299  * @param b another value
300  * @return sum with signed saturation
301  */
302 static av_always_inline int av_sat_add32_c(int a, int b)
303 {
304  return av_clipl_int32((int64_t)a + b);
305 }
306 
307 /**
308  * Add a doubled value to another value with saturation at both stages.
309  *
310  * @param a first value
311  * @param b value doubled and added to a
312  * @return sum sat(a + sat(2*b)) with signed saturation
313  */
314 static av_always_inline int av_sat_dadd32_c(int a, int b)
315 {
316  return av_sat_add32(a, av_sat_add32(b, b));
317 }
318 
319 /**
320  * Subtract two signed 32-bit values with saturation.
321  *
322  * @param a one value
323  * @param b another value
324  * @return difference with signed saturation
325  */
326 static av_always_inline int av_sat_sub32_c(int a, int b)
327 {
328  return av_clipl_int32((int64_t)a - b);
329 }
330 
331 /**
332  * Subtract a doubled value from another value with saturation at both stages.
333  *
334  * @param a first value
335  * @param b value doubled and subtracted from a
336  * @return difference sat(a - sat(2*b)) with signed saturation
337  */
338 static av_always_inline int av_sat_dsub32_c(int a, int b)
339 {
340  return av_sat_sub32(a, av_sat_add32(b, b));
341 }
342 
343 /**
344  * Add two signed 64-bit values with saturation.
345  *
346  * @param a one value
347  * @param b another value
348  * @return sum with signed saturation
349  */
350 static av_always_inline int64_t av_sat_add64_c(int64_t a, int64_t b) {
351 #if (!defined(__INTEL_COMPILER) && AV_GCC_VERSION_AT_LEAST(5,1)) || AV_HAS_BUILTIN(__builtin_add_overflow)
352  int64_t tmp;
353  return !__builtin_add_overflow(a, b, &tmp) ? tmp : (tmp < 0 ? INT64_MAX : INT64_MIN);
354 #else
355  int64_t s = a+(uint64_t)b;
356  if ((int64_t)(a^b | ~s^b) >= 0)
357  return INT64_MAX ^ (b >> 63);
358  return s;
359 #endif
360 }
361 
362 /**
363  * Subtract two signed 64-bit values with saturation.
364  *
365  * @param a one value
366  * @param b another value
367  * @return difference with signed saturation
368  */
369 static av_always_inline int64_t av_sat_sub64_c(int64_t a, int64_t b) {
370 #if (!defined(__INTEL_COMPILER) && AV_GCC_VERSION_AT_LEAST(5,1)) || AV_HAS_BUILTIN(__builtin_sub_overflow)
371  int64_t tmp;
372  return !__builtin_sub_overflow(a, b, &tmp) ? tmp : (tmp < 0 ? INT64_MAX : INT64_MIN);
373 #else
374  if (b <= 0 && a >= INT64_MAX + b)
375  return INT64_MAX;
376  if (b >= 0 && a <= INT64_MIN + b)
377  return INT64_MIN;
378  return a - b;
379 #endif
380 }
381 
382 /**
383  * Clip a float value into the amin-amax range.
384  * If a is nan or -inf amin will be returned.
385  * If a is +inf amax will be returned.
386  * @param a value to clip
387  * @param amin minimum value of the clip range
388  * @param amax maximum value of the clip range
389  * @return clipped value
390  */
391 static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
392 {
393 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
394  if (amin > amax) abort();
395 #endif
396  return FFMIN(FFMAX(a, amin), amax);
397 }
398 
399 /**
400  * Clip a double value into the amin-amax range.
401  * If a is nan or -inf amin will be returned.
402  * If a is +inf amax will be returned.
403  * @param a value to clip
404  * @param amin minimum value of the clip range
405  * @param amax maximum value of the clip range
406  * @return clipped value
407  */
408 static av_always_inline av_const double av_clipd_c(double a, double amin, double amax)
409 {
410 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
411  if (amin > amax) abort();
412 #endif
413  return FFMIN(FFMAX(a, amin), amax);
414 }
415 
416 /** Compute ceil(log2(x)).
417  * @param x value used to compute ceil(log2(x))
418  * @return computed ceiling of log2(x)
419  */
421 {
422  return av_log2((x - 1U) << 1);
423 }
424 
425 /**
426  * Count number of bits set to one in x
427  * @param x value to count bits of
428  * @return the number of bits set to one in x
429  */
431 {
432  x -= (x >> 1) & 0x55555555;
433  x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
434  x = (x + (x >> 4)) & 0x0F0F0F0F;
435  x += x >> 8;
436  return (x + (x >> 16)) & 0x3F;
437 }
438 
439 /**
440  * Count number of bits set to one in x
441  * @param x value to count bits of
442  * @return the number of bits set to one in x
443  */
445 {
446  return av_popcount((uint32_t)x) + av_popcount((uint32_t)(x >> 32));
447 }
448 
449 static av_always_inline av_const int av_parity_c(uint32_t v)
450 {
451  return av_popcount(v) & 1;
452 }
453 
454 /**
455  * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form.
456  *
457  * @param val Output value, must be an lvalue of type uint32_t.
458  * @param GET_BYTE Expression reading one byte from the input.
459  * Evaluated up to 7 times (4 for the currently
460  * assigned Unicode range). With a memory buffer
461  * input, this could be *ptr++, or if you want to make sure
462  * that *ptr stops at the end of a NULL terminated string then
463  * *ptr ? *ptr++ : 0
464  * @param ERROR Expression to be evaluated on invalid input,
465  * typically a goto statement.
466  *
467  * @warning ERROR should not contain a loop control statement which
468  * could interact with the internal while loop, and should force an
469  * exit from the macro code (e.g. through a goto or a return) in order
470  * to prevent undefined results.
471  */
472 #define GET_UTF8(val, GET_BYTE, ERROR)\
473  val= (GET_BYTE);\
474  {\
475  uint32_t top = (val & 128) >> 1;\
476  if ((val & 0xc0) == 0x80 || val >= 0xFE)\
477  {ERROR}\
478  while (val & top) {\
479  unsigned int tmp = (GET_BYTE) - 128;\
480  if(tmp>>6)\
481  {ERROR}\
482  val= (val<<6) + tmp;\
483  top <<= 5;\
484  }\
485  val &= (top << 1) - 1;\
486  }
487 
488 /**
489  * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form.
490  *
491  * @param val Output value, must be an lvalue of type uint32_t.
492  * @param GET_16BIT Expression returning two bytes of UTF-16 data converted
493  * to native byte order. Evaluated one or two times.
494  * @param ERROR Expression to be evaluated on invalid input,
495  * typically a goto statement.
496  */
497 #define GET_UTF16(val, GET_16BIT, ERROR)\
498  val = (GET_16BIT);\
499  {\
500  unsigned int hi = val - 0xD800;\
501  if (hi < 0x800) {\
502  val = (GET_16BIT) - 0xDC00;\
503  if (val > 0x3FFU || hi > 0x3FFU)\
504  {ERROR}\
505  val += (hi<<10) + 0x10000;\
506  }\
507  }\
508 
509 /**
510  * @def PUT_UTF8(val, tmp, PUT_BYTE)
511  * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).
512  * @param val is an input-only argument and should be of type uint32_t. It holds
513  * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If
514  * val is given as a function it is executed only once.
515  * @param tmp is a temporary variable and should be of type uint8_t. It
516  * represents an intermediate value during conversion that is to be
517  * output by PUT_BYTE.
518  * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
519  * It could be a function or a statement, and uses tmp as the input byte.
520  * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
521  * executed up to 4 times for values in the valid UTF-8 range and up to
522  * 7 times in the general case, depending on the length of the converted
523  * Unicode character.
524  */
525 #define PUT_UTF8(val, tmp, PUT_BYTE)\
526  {\
527  int bytes, shift;\
528  uint32_t in = val;\
529  if (in < 0x80) {\
530  tmp = in;\
531  PUT_BYTE\
532  } else {\
533  bytes = (av_log2(in) + 4) / 5;\
534  shift = (bytes - 1) * 6;\
535  tmp = (256 - (256 >> bytes)) | (in >> shift);\
536  PUT_BYTE\
537  while (shift >= 6) {\
538  shift -= 6;\
539  tmp = 0x80 | ((in >> shift) & 0x3f);\
540  PUT_BYTE\
541  }\
542  }\
543  }
544 
545 /**
546  * @def PUT_UTF16(val, tmp, PUT_16BIT)
547  * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes).
548  * @param val is an input-only argument and should be of type uint32_t. It holds
549  * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If
550  * val is given as a function it is executed only once.
551  * @param tmp is a temporary variable and should be of type uint16_t. It
552  * represents an intermediate value during conversion that is to be
553  * output by PUT_16BIT.
554  * @param PUT_16BIT writes the converted UTF-16 data to any proper destination
555  * in desired endianness. It could be a function or a statement, and uses tmp
556  * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;"
557  * PUT_BYTE will be executed 1 or 2 times depending on input character.
558  */
559 #define PUT_UTF16(val, tmp, PUT_16BIT)\
560  {\
561  uint32_t in = val;\
562  if (in < 0x10000) {\
563  tmp = in;\
564  PUT_16BIT\
565  } else {\
566  tmp = 0xD800 | ((in - 0x10000) >> 10);\
567  PUT_16BIT\
568  tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\
569  PUT_16BIT\
570  }\
571  }\
572 
573 #endif /* AVUTIL_COMMON_H */
av_mod_uintp2_c
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:290
av_log2_16bit
int av_log2_16bit(unsigned v)
Definition: intmath.c:31
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:28
av_clip_uintp2_c
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:278
av_sat_sub32_c
static av_always_inline int av_sat_sub32_c(int a, int b)
Subtract two signed 32-bit values with saturation.
Definition: common.h:326
av_const
#define av_const
Definition: attributes.h:84
b
#define b
Definition: input.c:41
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
av_popcount
#define av_popcount
Definition: common.h:152
av_clip_uint16_c
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:230
av_clip_uint8_c
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:208
av_sat_dadd32_c
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:314
av_clip64_c
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:193
macros.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
limits.h
av_sat_sub32
#define av_sat_sub32
Definition: common.h:134
av_clipf_c
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:391
av_clipd_c
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:408
av_clip_intp2_c
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:264
av_sat_add32
#define av_sat_add32
Definition: common.h:128
av_clip_c
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:176
error.h
av_clipl_int32
#define av_clipl_int32
Definition: common.h:116
a
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:41
attributes.h
internal.h
av_clipl_int32_c
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:252
av_always_inline
#define av_always_inline
Definition: attributes.h:49
av_popcount_c
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:430
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
av_sat_add32_c
static av_always_inline int av_sat_add32_c(int a, int b)
Add two signed 32-bit values with saturation.
Definition: common.h:302
av_popcount64_c
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:444
U
#define U(x)
Definition: vpx_arith.h:37
mem.h
av_sat_add64_c
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:350
av_clip_int16_c
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:241
av_sat_sub64_c
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:369
int32_t
int32_t
Definition: audioconvert.c:56
av_sat_dsub32_c
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:338
av_parity_c
static av_always_inline av_const int av_parity_c(uint32_t v)
Definition: common.h:449
av_log2
int av_log2(unsigned v)
Definition: intmath.c:26
av_ceil_log2_c
static av_always_inline av_const int av_ceil_log2_c(int x)
Compute ceil(log2(x)).
Definition: common.h:420
av_clip_int8_c
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:219
intmath.h