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)))
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.
92 #define FFDIFFSIGN(x,y) (((x)>(y)) - ((x)<(y)))
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)
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]))
102 /* misc math functions */
104 #ifdef HAVE_AV_CONFIG_H
106 # include "intmath.h"
109 /* Pull in unguarded fallback defines at the end of this file. */
113 av_const int av_log2(unsigned v);
116 #ifndef av_log2_16bit
117 av_const int av_log2_16bit(unsigned v);
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
127 static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
129 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
130 if (amin > amax) abort();
132 if (a < amin) return amin;
133 else if (a > amax) return amax;
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
144 static av_always_inline av_const int64_t av_clip64_c(int64_t a, int64_t amin, int64_t amax)
146 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
147 if (amin > amax) abort();
149 if (a < amin) return amin;
150 else if (a > amax) return amax;
155 * Clip a signed integer value into the 0-255 range.
156 * @param a value to clip
157 * @return clipped value
159 static av_always_inline av_const uint8_t av_clip_uint8_c(int a)
161 if (a&(~0xFF)) return (~a)>>31;
166 * Clip a signed integer value into the -128,127 range.
167 * @param a value to clip
168 * @return clipped value
170 static av_always_inline av_const int8_t av_clip_int8_c(int a)
172 if ((a+0x80U) & ~0xFF) return (a>>31) ^ 0x7F;
177 * Clip a signed integer value into the 0-65535 range.
178 * @param a value to clip
179 * @return clipped value
181 static av_always_inline av_const uint16_t av_clip_uint16_c(int a)
183 if (a&(~0xFFFF)) return (~a)>>31;
188 * Clip a signed integer value into the -32768,32767 range.
189 * @param a value to clip
190 * @return clipped value
192 static av_always_inline av_const int16_t av_clip_int16_c(int a)
194 if ((a+0x8000U) & ~0xFFFF) return (a>>31) ^ 0x7FFF;
199 * Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
200 * @param a value to clip
201 * @return clipped value
203 static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a)
205 if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (int32_t)((a>>63) ^ 0x7FFFFFFF);
206 else return (int32_t)a;
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
215 static av_always_inline av_const int av_clip_intp2_c(int a, int p)
217 if (((unsigned)a + (1 << p)) & ~((2 << p) - 1))
218 return (a >> 31) ^ ((1 << p) - 1);
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
229 static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
231 if (a & ~((1<<p) - 1)) return (~a) >> 31 & ((1<<p) - 1);
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
241 static av_always_inline av_const unsigned av_mod_uintp2_c(unsigned a, unsigned p)
243 return a & ((1U << p) - 1);
247 * Add two signed 32-bit values with saturation.
250 * @param b another value
251 * @return sum with signed saturation
253 static av_always_inline int av_sat_add32_c(int a, int b)
255 return av_clipl_int32((int64_t)a + b);
259 * Add a doubled value to another value with saturation at both stages.
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
265 static av_always_inline int av_sat_dadd32_c(int a, int b)
267 return av_sat_add32(a, av_sat_add32(b, b));
271 * Subtract two signed 32-bit values with saturation.
274 * @param b another value
275 * @return difference with signed saturation
277 static av_always_inline int av_sat_sub32_c(int a, int b)
279 return av_clipl_int32((int64_t)a - b);
283 * Subtract a doubled value from another value with saturation at both stages.
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
289 static av_always_inline int av_sat_dsub32_c(int a, int b)
291 return av_sat_sub32(a, av_sat_add32(b, b));
295 * Clip a float value into the amin-amax range.
296 * @param a value to clip
297 * @param amin minimum value of the clip range
298 * @param amax maximum value of the clip range
299 * @return clipped value
301 static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
303 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
304 if (amin > amax) abort();
306 if (a < amin) return amin;
307 else if (a > amax) return amax;
312 * Clip a double value into the amin-amax range.
313 * @param a value to clip
314 * @param amin minimum value of the clip range
315 * @param amax maximum value of the clip range
316 * @return clipped value
318 static av_always_inline av_const double av_clipd_c(double a, double amin, double amax)
320 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
321 if (amin > amax) abort();
323 if (a < amin) return amin;
324 else if (a > amax) return amax;
328 /** Compute ceil(log2(x)).
329 * @param x value used to compute ceil(log2(x))
330 * @return computed ceiling of log2(x)
332 static av_always_inline av_const int av_ceil_log2_c(int x)
334 return av_log2((x - 1) << 1);
338 * Count number of bits set to one in x
339 * @param x value to count bits of
340 * @return the number of bits set to one in x
342 static av_always_inline av_const int av_popcount_c(uint32_t x)
344 x -= (x >> 1) & 0x55555555;
345 x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
346 x = (x + (x >> 4)) & 0x0F0F0F0F;
348 return (x + (x >> 16)) & 0x3F;
352 * Count number of bits set to one in x
353 * @param x value to count bits of
354 * @return the number of bits set to one in x
356 static av_always_inline av_const int av_popcount64_c(uint64_t x)
358 return av_popcount((uint32_t)x) + av_popcount((uint32_t)(x >> 32));
361 static av_always_inline av_const int av_parity_c(uint32_t v)
363 return av_popcount(v) & 1;
366 #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))
367 #define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24))
370 * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form.
372 * @param val Output value, must be an lvalue of type uint32_t.
373 * @param GET_BYTE Expression reading one byte from the input.
374 * Evaluated up to 7 times (4 for the currently
375 * assigned Unicode range). With a memory buffer
376 * input, this could be *ptr++, or if you want to make sure
377 * that *ptr stops at the end of a NULL terminated string then
379 * @param ERROR Expression to be evaluated on invalid input,
380 * typically a goto statement.
382 * @warning ERROR should not contain a loop control statement which
383 * could interact with the internal while loop, and should force an
384 * exit from the macro code (e.g. through a goto or a return) in order
385 * to prevent undefined results.
387 #define GET_UTF8(val, GET_BYTE, ERROR)\
390 uint32_t top = (val & 128) >> 1;\
391 if ((val & 0xc0) == 0x80 || val >= 0xFE)\
394 unsigned int tmp = (GET_BYTE) - 128;\
397 val= (val<<6) + tmp;\
400 val &= (top << 1) - 1;\
404 * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form.
406 * @param val Output value, must be an lvalue of type uint32_t.
407 * @param GET_16BIT Expression returning two bytes of UTF-16 data converted
408 * to native byte order. Evaluated one or two times.
409 * @param ERROR Expression to be evaluated on invalid input,
410 * typically a goto statement.
412 #define GET_UTF16(val, GET_16BIT, ERROR)\
415 unsigned int hi = val - 0xD800;\
417 val = (GET_16BIT) - 0xDC00;\
418 if (val > 0x3FFU || hi > 0x3FFU)\
420 val += (hi<<10) + 0x10000;\
425 * @def PUT_UTF8(val, tmp, PUT_BYTE)
426 * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).
427 * @param val is an input-only argument and should be of type uint32_t. It holds
428 * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If
429 * val is given as a function it is executed only once.
430 * @param tmp is a temporary variable and should be of type uint8_t. It
431 * represents an intermediate value during conversion that is to be
432 * output by PUT_BYTE.
433 * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
434 * It could be a function or a statement, and uses tmp as the input byte.
435 * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
436 * executed up to 4 times for values in the valid UTF-8 range and up to
437 * 7 times in the general case, depending on the length of the converted
440 #define PUT_UTF8(val, tmp, PUT_BYTE)\
448 bytes = (av_log2(in) + 4) / 5;\
449 shift = (bytes - 1) * 6;\
450 tmp = (256 - (256 >> bytes)) | (in >> shift);\
452 while (shift >= 6) {\
454 tmp = 0x80 | ((in >> shift) & 0x3f);\
461 * @def PUT_UTF16(val, tmp, PUT_16BIT)
462 * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes).
463 * @param val is an input-only argument and should be of type uint32_t. It holds
464 * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If
465 * val is given as a function it is executed only once.
466 * @param tmp is a temporary variable and should be of type uint16_t. It
467 * represents an intermediate value during conversion that is to be
468 * output by PUT_16BIT.
469 * @param PUT_16BIT writes the converted UTF-16 data to any proper destination
470 * in desired endianness. It could be a function or a statement, and uses tmp
471 * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;"
472 * PUT_BYTE will be executed 1 or 2 times depending on input character.
474 #define PUT_UTF16(val, tmp, PUT_16BIT)\
481 tmp = 0xD800 | ((in - 0x10000) >> 10);\
483 tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\
492 #ifdef HAVE_AV_CONFIG_H
493 # include "internal.h"
494 #endif /* HAVE_AV_CONFIG_H */
496 #endif /* AVUTIL_COMMON_H */
499 * The following definitions are outside the multiple inclusion guard
500 * to ensure they are immediately available in intmath.h.
504 # define av_ceil_log2 av_ceil_log2_c
507 # define av_clip av_clip_c
510 # define av_clip64 av_clip64_c
512 #ifndef av_clip_uint8
513 # define av_clip_uint8 av_clip_uint8_c
516 # define av_clip_int8 av_clip_int8_c
518 #ifndef av_clip_uint16
519 # define av_clip_uint16 av_clip_uint16_c
521 #ifndef av_clip_int16
522 # define av_clip_int16 av_clip_int16_c
524 #ifndef av_clipl_int32
525 # define av_clipl_int32 av_clipl_int32_c
527 #ifndef av_clip_intp2
528 # define av_clip_intp2 av_clip_intp2_c
530 #ifndef av_clip_uintp2
531 # define av_clip_uintp2 av_clip_uintp2_c
533 #ifndef av_mod_uintp2
534 # define av_mod_uintp2 av_mod_uintp2_c
537 # define av_sat_add32 av_sat_add32_c
539 #ifndef av_sat_dadd32
540 # define av_sat_dadd32 av_sat_dadd32_c
543 # define av_sat_sub32 av_sat_sub32_c
545 #ifndef av_sat_dsub32
546 # define av_sat_dsub32 av_sat_dsub32_c
549 # define av_clipf av_clipf_c
552 # define av_clipd av_clipd_c
555 # define av_popcount av_popcount_c
557 #ifndef av_popcount64
558 # define av_popcount64 av_popcount64_c
561 # define av_parity av_parity_c