2 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
4 * This file is part of FFmpeg.
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.
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.
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
23 * common internal and external API header
26 #ifndef AVUTIL_COMMON_H
27 #define AVUTIL_COMMON_H
29 #if defined(__cplusplus) && !defined(__STDC_CONSTANT_MACROS) && !defined(UINT64_C)
30 #error missing -D__STDC_CONSTANT_MACROS / #define __STDC_CONSTANT_MACROS
42 #include "attributes.h"
45 #include "libavutil/avconfig.h"
48 # define AV_NE(be, le) (be)
50 # define AV_NE(be, le) (le)
53 //rounded division & shift
54 #define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
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
63 #define FFUDIV(a,b) (((a)>0 ?(a):(a)-(b)+1) / (b))
64 #define FFUMOD(a,b) ((a)-(b)*FFUDIV(a,b))
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
72 #define FFABS(a) ((a) >= 0 ? (a) : (-(a)))
73 #define FFSIGN(a) ((a) > 0 ? 1 : -1)
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.
81 #define FFNABS(a) ((a) <= 0 ? (a) : (-(a)))
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.
89 #define FFABSU(a) ((a) <= 0 ? -(unsigned)(a) : (unsigned)(a))
93 * For two numerical expressions x and y, gives 1 if x > y, -1 if x < y, and 0
94 * if x == y. This is useful for instance in a qsort comparator callback.
95 * Furthermore, compilers are able to optimize this to branchless code, and
96 * there is no risk of overflow with signed types.
97 * As with many macros, this evaluates its argument multiple times, it thus
98 * must not have a side-effect.
100 #define FFDIFFSIGN(x,y) (((x)>(y)) - ((x)<(y)))
102 #define FFMAX(a,b) ((a) > (b) ? (a) : (b))
103 #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c)
104 #define FFMIN(a,b) ((a) > (b) ? (b) : (a))
105 #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c)
107 #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
108 #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))
110 /* misc math functions */
112 #ifdef HAVE_AV_CONFIG_H
114 # include "intmath.h"
117 /* Pull in unguarded fallback defines at the end of this file. */
121 av_const int av_log2(unsigned v);
124 #ifndef av_log2_16bit
125 av_const int av_log2_16bit(unsigned v);
129 * Clip a signed integer value into the amin-amax range.
130 * @param a value to clip
131 * @param amin minimum value of the clip range
132 * @param amax maximum value of the clip range
133 * @return clipped value
135 static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
137 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
138 if (amin > amax) abort();
140 if (a < amin) return amin;
141 else if (a > amax) return amax;
146 * Clip a signed 64bit integer value into the amin-amax range.
147 * @param a value to clip
148 * @param amin minimum value of the clip range
149 * @param amax maximum value of the clip range
150 * @return clipped value
152 static av_always_inline av_const int64_t av_clip64_c(int64_t a, int64_t amin, int64_t amax)
154 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
155 if (amin > amax) abort();
157 if (a < amin) return amin;
158 else if (a > amax) return amax;
163 * Clip a signed integer value into the 0-255 range.
164 * @param a value to clip
165 * @return clipped value
167 static av_always_inline av_const uint8_t av_clip_uint8_c(int a)
169 if (a&(~0xFF)) return (~a)>>31;
174 * Clip a signed integer value into the -128,127 range.
175 * @param a value to clip
176 * @return clipped value
178 static av_always_inline av_const int8_t av_clip_int8_c(int a)
180 if ((a+0x80U) & ~0xFF) return (a>>31) ^ 0x7F;
185 * Clip a signed integer value into the 0-65535 range.
186 * @param a value to clip
187 * @return clipped value
189 static av_always_inline av_const uint16_t av_clip_uint16_c(int a)
191 if (a&(~0xFFFF)) return (~a)>>31;
196 * Clip a signed integer value into the -32768,32767 range.
197 * @param a value to clip
198 * @return clipped value
200 static av_always_inline av_const int16_t av_clip_int16_c(int a)
202 if ((a+0x8000U) & ~0xFFFF) return (a>>31) ^ 0x7FFF;
207 * Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
208 * @param a value to clip
209 * @return clipped value
211 static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a)
213 if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (int32_t)((a>>63) ^ 0x7FFFFFFF);
214 else return (int32_t)a;
218 * Clip a signed integer into the -(2^p),(2^p-1) range.
219 * @param a value to clip
220 * @param p bit position to clip at
221 * @return clipped value
223 static av_always_inline av_const int av_clip_intp2_c(int a, int p)
225 if (((unsigned)a + (1 << p)) & ~((2 << p) - 1))
226 return (a >> 31) ^ ((1 << p) - 1);
232 * Clip a signed integer to an unsigned power of two range.
233 * @param a value to clip
234 * @param p bit position to clip at
235 * @return clipped value
237 static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
239 if (a & ~((1<<p) - 1)) return (~a) >> 31 & ((1<<p) - 1);
244 * Clear high bits from an unsigned integer starting with specific bit position
245 * @param a value to clip
246 * @param p bit position to clip at
247 * @return clipped value
249 static av_always_inline av_const unsigned av_mod_uintp2_c(unsigned a, unsigned p)
251 return a & ((1U << p) - 1);
255 * Add two signed 32-bit values with saturation.
258 * @param b another value
259 * @return sum with signed saturation
261 static av_always_inline int av_sat_add32_c(int a, int b)
263 return av_clipl_int32((int64_t)a + b);
267 * Add a doubled value to another value with saturation at both stages.
269 * @param a first value
270 * @param b value doubled and added to a
271 * @return sum sat(a + sat(2*b)) with signed saturation
273 static av_always_inline int av_sat_dadd32_c(int a, int b)
275 return av_sat_add32(a, av_sat_add32(b, b));
279 * Subtract two signed 32-bit values with saturation.
282 * @param b another value
283 * @return difference with signed saturation
285 static av_always_inline int av_sat_sub32_c(int a, int b)
287 return av_clipl_int32((int64_t)a - b);
291 * Subtract a doubled value from another value with saturation at both stages.
293 * @param a first value
294 * @param b value doubled and subtracted from a
295 * @return difference sat(a - sat(2*b)) with signed saturation
297 static av_always_inline int av_sat_dsub32_c(int a, int b)
299 return av_sat_sub32(a, av_sat_add32(b, b));
303 * Add two signed 64-bit values with saturation.
306 * @param b another value
307 * @return sum with signed saturation
309 static av_always_inline int64_t av_sat_add64_c(int64_t a, int64_t b) {
310 #if (!defined(__INTEL_COMPILER) && AV_GCC_VERSION_AT_LEAST(5,1)) || AV_HAS_BUILTIN(__builtin_add_overflow)
312 return !__builtin_add_overflow(a, b, &tmp) ? tmp : (tmp < 0 ? INT64_MAX : INT64_MIN);
314 int64_t s = a+(uint64_t)b;
315 if ((int64_t)(a^b | ~s^b) >= 0)
316 return INT64_MAX ^ (b >> 63);
322 * Subtract two signed 64-bit values with saturation.
325 * @param b another value
326 * @return difference with signed saturation
328 static av_always_inline int64_t av_sat_sub64_c(int64_t a, int64_t b) {
329 #if (!defined(__INTEL_COMPILER) && AV_GCC_VERSION_AT_LEAST(5,1)) || AV_HAS_BUILTIN(__builtin_sub_overflow)
331 return !__builtin_sub_overflow(a, b, &tmp) ? tmp : (tmp < 0 ? INT64_MAX : INT64_MIN);
333 if (b <= 0 && a >= INT64_MAX + b)
335 if (b >= 0 && a <= INT64_MIN + b)
342 * Clip a float 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
348 static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
350 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
351 if (amin > amax) abort();
353 if (a < amin) return amin;
354 else if (a > amax) return amax;
359 * Clip a double value into the amin-amax range.
360 * @param a value to clip
361 * @param amin minimum value of the clip range
362 * @param amax maximum value of the clip range
363 * @return clipped value
365 static av_always_inline av_const double av_clipd_c(double a, double amin, double amax)
367 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
368 if (amin > amax) abort();
370 if (a < amin) return amin;
371 else if (a > amax) return amax;
375 /** Compute ceil(log2(x)).
376 * @param x value used to compute ceil(log2(x))
377 * @return computed ceiling of log2(x)
379 static av_always_inline av_const int av_ceil_log2_c(int x)
381 return av_log2((x - 1U) << 1);
385 * Count number of bits set to one in x
386 * @param x value to count bits of
387 * @return the number of bits set to one in x
389 static av_always_inline av_const int av_popcount_c(uint32_t x)
391 x -= (x >> 1) & 0x55555555;
392 x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
393 x = (x + (x >> 4)) & 0x0F0F0F0F;
395 return (x + (x >> 16)) & 0x3F;
399 * Count number of bits set to one in x
400 * @param x value to count bits of
401 * @return the number of bits set to one in x
403 static av_always_inline av_const int av_popcount64_c(uint64_t x)
405 return av_popcount((uint32_t)x) + av_popcount((uint32_t)(x >> 32));
408 static av_always_inline av_const int av_parity_c(uint32_t v)
410 return av_popcount(v) & 1;
413 #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))
414 #define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24))
417 * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form.
419 * @param val Output value, must be an lvalue of type uint32_t.
420 * @param GET_BYTE Expression reading one byte from the input.
421 * Evaluated up to 7 times (4 for the currently
422 * assigned Unicode range). With a memory buffer
423 * input, this could be *ptr++, or if you want to make sure
424 * that *ptr stops at the end of a NULL terminated string then
426 * @param ERROR Expression to be evaluated on invalid input,
427 * typically a goto statement.
429 * @warning ERROR should not contain a loop control statement which
430 * could interact with the internal while loop, and should force an
431 * exit from the macro code (e.g. through a goto or a return) in order
432 * to prevent undefined results.
434 #define GET_UTF8(val, GET_BYTE, ERROR)\
437 uint32_t top = (val & 128) >> 1;\
438 if ((val & 0xc0) == 0x80 || val >= 0xFE)\
441 unsigned int tmp = (GET_BYTE) - 128;\
444 val= (val<<6) + tmp;\
447 val &= (top << 1) - 1;\
451 * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form.
453 * @param val Output value, must be an lvalue of type uint32_t.
454 * @param GET_16BIT Expression returning two bytes of UTF-16 data converted
455 * to native byte order. Evaluated one or two times.
456 * @param ERROR Expression to be evaluated on invalid input,
457 * typically a goto statement.
459 #define GET_UTF16(val, GET_16BIT, ERROR)\
462 unsigned int hi = val - 0xD800;\
464 val = (GET_16BIT) - 0xDC00;\
465 if (val > 0x3FFU || hi > 0x3FFU)\
467 val += (hi<<10) + 0x10000;\
472 * @def PUT_UTF8(val, tmp, PUT_BYTE)
473 * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).
474 * @param val is an input-only argument and should be of type uint32_t. It holds
475 * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If
476 * val is given as a function it is executed only once.
477 * @param tmp is a temporary variable and should be of type uint8_t. It
478 * represents an intermediate value during conversion that is to be
479 * output by PUT_BYTE.
480 * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
481 * It could be a function or a statement, and uses tmp as the input byte.
482 * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
483 * executed up to 4 times for values in the valid UTF-8 range and up to
484 * 7 times in the general case, depending on the length of the converted
487 #define PUT_UTF8(val, tmp, PUT_BYTE)\
495 bytes = (av_log2(in) + 4) / 5;\
496 shift = (bytes - 1) * 6;\
497 tmp = (256 - (256 >> bytes)) | (in >> shift);\
499 while (shift >= 6) {\
501 tmp = 0x80 | ((in >> shift) & 0x3f);\
508 * @def PUT_UTF16(val, tmp, PUT_16BIT)
509 * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes).
510 * @param val is an input-only argument and should be of type uint32_t. It holds
511 * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If
512 * val is given as a function it is executed only once.
513 * @param tmp is a temporary variable and should be of type uint16_t. It
514 * represents an intermediate value during conversion that is to be
515 * output by PUT_16BIT.
516 * @param PUT_16BIT writes the converted UTF-16 data to any proper destination
517 * in desired endianness. It could be a function or a statement, and uses tmp
518 * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;"
519 * PUT_BYTE will be executed 1 or 2 times depending on input character.
521 #define PUT_UTF16(val, tmp, PUT_16BIT)\
528 tmp = 0xD800 | ((in - 0x10000) >> 10);\
530 tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\
539 #ifdef HAVE_AV_CONFIG_H
540 # include "internal.h"
541 #endif /* HAVE_AV_CONFIG_H */
543 #endif /* AVUTIL_COMMON_H */
546 * The following definitions are outside the multiple inclusion guard
547 * to ensure they are immediately available in intmath.h.
551 # define av_ceil_log2 av_ceil_log2_c
554 # define av_clip av_clip_c
557 # define av_clip64 av_clip64_c
559 #ifndef av_clip_uint8
560 # define av_clip_uint8 av_clip_uint8_c
563 # define av_clip_int8 av_clip_int8_c
565 #ifndef av_clip_uint16
566 # define av_clip_uint16 av_clip_uint16_c
568 #ifndef av_clip_int16
569 # define av_clip_int16 av_clip_int16_c
571 #ifndef av_clipl_int32
572 # define av_clipl_int32 av_clipl_int32_c
574 #ifndef av_clip_intp2
575 # define av_clip_intp2 av_clip_intp2_c
577 #ifndef av_clip_uintp2
578 # define av_clip_uintp2 av_clip_uintp2_c
580 #ifndef av_mod_uintp2
581 # define av_mod_uintp2 av_mod_uintp2_c
584 # define av_sat_add32 av_sat_add32_c
586 #ifndef av_sat_dadd32
587 # define av_sat_dadd32 av_sat_dadd32_c
590 # define av_sat_sub32 av_sat_sub32_c
592 #ifndef av_sat_dsub32
593 # define av_sat_dsub32 av_sat_dsub32_c
596 # define av_sat_add64 av_sat_add64_c
599 # define av_sat_sub64 av_sat_sub64_c
602 # define av_clipf av_clipf_c
605 # define av_clipd av_clipd_c
608 # define av_popcount av_popcount_c
610 #ifndef av_popcount64
611 # define av_popcount64 av_popcount64_c
614 # define av_parity av_parity_c