2 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
4 * This file is part of Libav.
6 * Libav 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 * Libav 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 Libav; 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
38 #include "attributes.h"
41 #include "libavutil/avconfig.h"
44 # define AV_NE(be, le) (be)
46 # define AV_NE(be, le) (le)
49 //rounded division & shift
50 #define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
52 #define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
55 * Fast a / (1 << b) rounded toward +inf, assuming a >= 0 and b >= 0.
57 #define AV_CEIL_RSHIFT(a, b) \
58 (av_builtin_constant_p(b) ? ((a) + (1 << (b)) - 1) >> (b) \
61 #define FFABS(a) ((a) >= 0 ? (a) : (-(a)))
62 #define FFSIGN(a) ((a) > 0 ? 1 : -1)
64 #define FFMAX(a,b) ((a) > (b) ? (a) : (b))
65 #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c)
66 #define FFMIN(a,b) ((a) > (b) ? (b) : (a))
67 #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c)
69 #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
70 #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))
72 /* misc math functions */
74 #ifdef HAVE_AV_CONFIG_H
79 /* Pull in unguarded fallback defines at the end of this file. */
83 av_const int av_log2(unsigned v);
87 av_const int av_log2_16bit(unsigned v);
91 * Clip a signed integer value into the amin-amax range.
92 * @param a value to clip
93 * @param amin minimum value of the clip range
94 * @param amax maximum value of the clip range
95 * @return clipped value
97 static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
99 if (a < amin) return amin;
100 else if (a > amax) return amax;
105 * Clip a signed integer value into the 0-255 range.
106 * @param a value to clip
107 * @return clipped value
109 static av_always_inline av_const uint8_t av_clip_uint8_c(int a)
111 if (a&(~0xFF)) return (-a)>>31;
116 * Clip a signed integer value into the -128,127 range.
117 * @param a value to clip
118 * @return clipped value
120 static av_always_inline av_const int8_t av_clip_int8_c(int a)
122 if ((a+0x80) & ~0xFF) return (a>>31) ^ 0x7F;
127 * Clip a signed integer value into the 0-65535 range.
128 * @param a value to clip
129 * @return clipped value
131 static av_always_inline av_const uint16_t av_clip_uint16_c(int a)
133 if (a&(~0xFFFF)) return (-a)>>31;
138 * Clip a signed integer value into the -32768,32767 range.
139 * @param a value to clip
140 * @return clipped value
142 static av_always_inline av_const int16_t av_clip_int16_c(int a)
144 if ((a+0x8000) & ~0xFFFF) return (a>>31) ^ 0x7FFF;
149 * Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
150 * @param a value to clip
151 * @return clipped value
153 static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a)
155 if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (a>>63) ^ 0x7FFFFFFF;
160 * Clip a signed integer into the -(2^p),(2^p-1) range.
161 * @param a value to clip
162 * @param p bit position to clip at
163 * @return clipped value
165 static av_always_inline av_const int av_clip_intp2_c(int a, int p)
167 if ((a + (1 << p)) & ~((1 << (p + 1)) - 1))
168 return (a >> 31) ^ ((1 << p) - 1);
174 * Clip a signed integer to an unsigned power of two range.
175 * @param a value to clip
176 * @param p bit position to clip at
177 * @return clipped value
179 static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
181 if (a & ~((1<<p) - 1)) return -a >> 31 & ((1<<p) - 1);
186 * Add two signed 32-bit values with saturation.
189 * @param b another value
190 * @return sum with signed saturation
192 static av_always_inline int av_sat_add32_c(int a, int b)
194 return av_clipl_int32((int64_t)a + b);
198 * Add a doubled value to another value with saturation at both stages.
200 * @param a first value
201 * @param b value doubled and added to a
202 * @return sum with signed saturation
204 static av_always_inline int av_sat_dadd32_c(int a, int b)
206 return av_sat_add32(a, av_sat_add32(b, b));
210 * Clip a float value into the amin-amax range.
211 * @param a value to clip
212 * @param amin minimum value of the clip range
213 * @param amax maximum value of the clip range
214 * @return clipped value
216 static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
218 if (a < amin) return amin;
219 else if (a > amax) return amax;
223 /** Compute ceil(log2(x)).
224 * @param x value used to compute ceil(log2(x))
225 * @return computed ceiling of log2(x)
227 static av_always_inline av_const int av_ceil_log2_c(int x)
229 return av_log2((x - 1) << 1);
233 * Count number of bits set to one in x
234 * @param x value to count bits of
235 * @return the number of bits set to one in x
237 static av_always_inline av_const int av_popcount_c(uint32_t x)
239 x -= (x >> 1) & 0x55555555;
240 x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
241 x = (x + (x >> 4)) & 0x0F0F0F0F;
243 return (x + (x >> 16)) & 0x3F;
247 * Count number of bits set to one in x
248 * @param x value to count bits of
249 * @return the number of bits set to one in x
251 static av_always_inline av_const int av_popcount64_c(uint64_t x)
253 return av_popcount(x) + av_popcount(x >> 32);
256 #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))
257 #define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24))
260 * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form.
262 * @param val Output value, must be an lvalue of type uint32_t.
263 * @param GET_BYTE Expression reading one byte from the input.
264 * Evaluated up to 7 times (4 for the currently
265 * assigned Unicode range). With a memory buffer
266 * input, this could be *ptr++.
267 * @param ERROR Expression to be evaluated on invalid input,
268 * typically a goto statement.
270 #define GET_UTF8(val, GET_BYTE, ERROR)\
273 uint32_t top = (val & 128) >> 1;\
274 if ((val & 0xc0) == 0x80)\
277 int tmp= GET_BYTE - 128;\
280 val= (val<<6) + tmp;\
283 val &= (top << 1) - 1;\
287 * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form.
289 * @param val Output value, must be an lvalue of type uint32_t.
290 * @param GET_16BIT Expression returning two bytes of UTF-16 data converted
291 * to native byte order. Evaluated one or two times.
292 * @param ERROR Expression to be evaluated on invalid input,
293 * typically a goto statement.
295 #define GET_UTF16(val, GET_16BIT, ERROR)\
298 unsigned int hi = val - 0xD800;\
300 val = GET_16BIT - 0xDC00;\
301 if (val > 0x3FFU || hi > 0x3FFU)\
303 val += (hi<<10) + 0x10000;\
308 * @def PUT_UTF8(val, tmp, PUT_BYTE)
309 * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).
310 * @param val is an input-only argument and should be of type uint32_t. It holds
311 * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If
312 * val is given as a function it is executed only once.
313 * @param tmp is a temporary variable and should be of type uint8_t. It
314 * represents an intermediate value during conversion that is to be
315 * output by PUT_BYTE.
316 * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
317 * It could be a function or a statement, and uses tmp as the input byte.
318 * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
319 * executed up to 4 times for values in the valid UTF-8 range and up to
320 * 7 times in the general case, depending on the length of the converted
323 #define PUT_UTF8(val, tmp, PUT_BYTE)\
331 bytes = (av_log2(in) + 4) / 5;\
332 shift = (bytes - 1) * 6;\
333 tmp = (256 - (256 >> bytes)) | (in >> shift);\
335 while (shift >= 6) {\
337 tmp = 0x80 | ((in >> shift) & 0x3f);\
344 * @def PUT_UTF16(val, tmp, PUT_16BIT)
345 * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes).
346 * @param val is an input-only argument and should be of type uint32_t. It holds
347 * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If
348 * val is given as a function it is executed only once.
349 * @param tmp is a temporary variable and should be of type uint16_t. It
350 * represents an intermediate value during conversion that is to be
351 * output by PUT_16BIT.
352 * @param PUT_16BIT writes the converted UTF-16 data to any proper destination
353 * in desired endianness. It could be a function or a statement, and uses tmp
354 * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;"
355 * PUT_BYTE will be executed 1 or 2 times depending on input character.
357 #define PUT_UTF16(val, tmp, PUT_16BIT)\
364 tmp = 0xD800 | ((in - 0x10000) >> 10);\
366 tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\
375 #ifdef HAVE_AV_CONFIG_H
376 # include "internal.h"
377 #endif /* HAVE_AV_CONFIG_H */
379 #endif /* AVUTIL_COMMON_H */
382 * The following definitions are outside the multiple inclusion guard
383 * to ensure they are immediately available in intmath.h.
387 # define av_ceil_log2 av_ceil_log2_c
390 # define av_clip av_clip_c
392 #ifndef av_clip_uint8
393 # define av_clip_uint8 av_clip_uint8_c
396 # define av_clip_int8 av_clip_int8_c
398 #ifndef av_clip_uint16
399 # define av_clip_uint16 av_clip_uint16_c
401 #ifndef av_clip_int16
402 # define av_clip_int16 av_clip_int16_c
404 #ifndef av_clipl_int32
405 # define av_clipl_int32 av_clipl_int32_c
407 #ifndef av_clip_intp2
408 # define av_clip_intp2 av_clip_intp2_c
410 #ifndef av_clip_uintp2
411 # define av_clip_uintp2 av_clip_uintp2_c
414 # define av_sat_add32 av_sat_add32_c
416 #ifndef av_sat_dadd32
417 # define av_sat_dadd32 av_sat_dadd32_c
420 # define av_clipf av_clipf_c
423 # define av_popcount av_popcount_c
425 #ifndef av_popcount64
426 # define av_popcount64 av_popcount64_c