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
37 #include "attributes.h"
39 #include "libavutil/avconfig.h"
42 # define AV_NE(be, le) (be)
44 # define AV_NE(be, le) (le)
47 //rounded division & shift
48 #define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
50 #define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
51 #define FFABS(a) ((a) >= 0 ? (a) : (-(a)))
52 #define FFSIGN(a) ((a) > 0 ? 1 : -1)
54 #define FFMAX(a,b) ((a) > (b) ? (a) : (b))
55 #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c)
56 #define FFMIN(a,b) ((a) > (b) ? (b) : (a))
57 #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c)
59 #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
60 #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))
61 #define FFALIGN(x, a) (((x)+(a)-1)&~((a)-1))
63 /* misc math functions */
66 extern attribute_deprecated const uint8_t av_reverse[256];
69 #ifdef HAVE_AV_CONFIG_H
74 /* Pull in unguarded fallback defines at the end of this file. */
78 av_const int av_log2(unsigned v);
82 av_const int av_log2_16bit(unsigned v);
86 * Clip a signed integer value into the amin-amax range.
87 * @param a value to clip
88 * @param amin minimum value of the clip range
89 * @param amax maximum value of the clip range
90 * @return clipped value
92 static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
94 if (a < amin) return amin;
95 else if (a > amax) return amax;
100 * Clip a signed integer value into the 0-255 range.
101 * @param a value to clip
102 * @return clipped value
104 static av_always_inline av_const uint8_t av_clip_uint8_c(int a)
106 if (a&(~0xFF)) return (-a)>>31;
111 * Clip a signed integer value into the -128,127 range.
112 * @param a value to clip
113 * @return clipped value
115 static av_always_inline av_const int8_t av_clip_int8_c(int a)
117 if ((a+0x80) & ~0xFF) return (a>>31) ^ 0x7F;
122 * Clip a signed integer value into the 0-65535 range.
123 * @param a value to clip
124 * @return clipped value
126 static av_always_inline av_const uint16_t av_clip_uint16_c(int a)
128 if (a&(~0xFFFF)) return (-a)>>31;
133 * Clip a signed integer value into the -32768,32767 range.
134 * @param a value to clip
135 * @return clipped value
137 static av_always_inline av_const int16_t av_clip_int16_c(int a)
139 if ((a+0x8000) & ~0xFFFF) return (a>>31) ^ 0x7FFF;
144 * Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
145 * @param a value to clip
146 * @return clipped value
148 static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a)
150 if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (a>>63) ^ 0x7FFFFFFF;
155 * Clip a signed integer to an unsigned power of two range.
156 * @param a value to clip
157 * @param p bit position to clip at
158 * @return clipped value
160 static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
162 if (a & ~((1<<p) - 1)) return -a >> 31 & ((1<<p) - 1);
167 * Add two signed 32-bit values with saturation.
170 * @param b another value
171 * @return sum with signed saturation
173 static av_always_inline int av_sat_add32_c(int a, int b)
175 return av_clipl_int32((int64_t)a + b);
179 * Add a doubled value to another value with saturation at both stages.
181 * @param a first value
182 * @param b value doubled and added to a
183 * @return sum with signed saturation
185 static av_always_inline int av_sat_dadd32_c(int a, int b)
187 return av_sat_add32(a, av_sat_add32(b, b));
191 * Clip a float value into the amin-amax range.
192 * @param a value to clip
193 * @param amin minimum value of the clip range
194 * @param amax maximum value of the clip range
195 * @return clipped value
197 static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
199 if (a < amin) return amin;
200 else if (a > amax) return amax;
204 /** Compute ceil(log2(x)).
205 * @param x value used to compute ceil(log2(x))
206 * @return computed ceiling of log2(x)
208 static av_always_inline av_const int av_ceil_log2_c(int x)
210 return av_log2((x - 1) << 1);
214 * Count number of bits set to one in x
215 * @param x value to count bits of
216 * @return the number of bits set to one in x
218 static av_always_inline av_const int av_popcount_c(uint32_t x)
220 x -= (x >> 1) & 0x55555555;
221 x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
222 x = (x + (x >> 4)) & 0x0F0F0F0F;
224 return (x + (x >> 16)) & 0x3F;
228 * Count number of bits set to one in x
229 * @param x value to count bits of
230 * @return the number of bits set to one in x
232 static av_always_inline av_const int av_popcount64_c(uint64_t x)
234 return av_popcount(x) + av_popcount(x >> 32);
237 #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))
238 #define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24))
241 * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form.
243 * @param val Output value, must be an lvalue of type uint32_t.
244 * @param GET_BYTE Expression reading one byte from the input.
245 * Evaluated up to 7 times (4 for the currently
246 * assigned Unicode range). With a memory buffer
247 * input, this could be *ptr++.
248 * @param ERROR Expression to be evaluated on invalid input,
249 * typically a goto statement.
251 #define GET_UTF8(val, GET_BYTE, ERROR)\
254 uint32_t top = (val & 128) >> 1;\
255 if ((val & 0xc0) == 0x80)\
258 int tmp= GET_BYTE - 128;\
261 val= (val<<6) + tmp;\
264 val &= (top << 1) - 1;\
268 * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form.
270 * @param val Output value, must be an lvalue of type uint32_t.
271 * @param GET_16BIT Expression returning two bytes of UTF-16 data converted
272 * to native byte order. Evaluated one or two times.
273 * @param ERROR Expression to be evaluated on invalid input,
274 * typically a goto statement.
276 #define GET_UTF16(val, GET_16BIT, ERROR)\
279 unsigned int hi = val - 0xD800;\
281 val = GET_16BIT - 0xDC00;\
282 if (val > 0x3FFU || hi > 0x3FFU)\
284 val += (hi<<10) + 0x10000;\
289 * @def PUT_UTF8(val, tmp, PUT_BYTE)
290 * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).
291 * @param val is an input-only argument and should be of type uint32_t. It holds
292 * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If
293 * val is given as a function it is executed only once.
294 * @param tmp is a temporary variable and should be of type uint8_t. It
295 * represents an intermediate value during conversion that is to be
296 * output by PUT_BYTE.
297 * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
298 * It could be a function or a statement, and uses tmp as the input byte.
299 * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
300 * executed up to 4 times for values in the valid UTF-8 range and up to
301 * 7 times in the general case, depending on the length of the converted
304 #define PUT_UTF8(val, tmp, PUT_BYTE)\
312 bytes = (av_log2(in) + 4) / 5;\
313 shift = (bytes - 1) * 6;\
314 tmp = (256 - (256 >> bytes)) | (in >> shift);\
316 while (shift >= 6) {\
318 tmp = 0x80 | ((in >> shift) & 0x3f);\
325 * @def PUT_UTF16(val, tmp, PUT_16BIT)
326 * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes).
327 * @param val is an input-only argument and should be of type uint32_t. It holds
328 * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If
329 * val is given as a function it is executed only once.
330 * @param tmp is a temporary variable and should be of type uint16_t. It
331 * represents an intermediate value during conversion that is to be
332 * output by PUT_16BIT.
333 * @param PUT_16BIT writes the converted UTF-16 data to any proper destination
334 * in desired endianness. It could be a function or a statement, and uses tmp
335 * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;"
336 * PUT_BYTE will be executed 1 or 2 times depending on input character.
338 #define PUT_UTF16(val, tmp, PUT_16BIT)\
345 tmp = 0xD800 | ((in - 0x10000) >> 10);\
347 tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\
356 #ifdef HAVE_AV_CONFIG_H
357 # include "internal.h"
358 #endif /* HAVE_AV_CONFIG_H */
360 #endif /* AVUTIL_COMMON_H */
363 * The following definitions are outside the multiple inclusion guard
364 * to ensure they are immediately available in intmath.h.
368 # define av_ceil_log2 av_ceil_log2_c
371 # define av_clip av_clip_c
373 #ifndef av_clip_uint8
374 # define av_clip_uint8 av_clip_uint8_c
377 # define av_clip_int8 av_clip_int8_c
379 #ifndef av_clip_uint16
380 # define av_clip_uint16 av_clip_uint16_c
382 #ifndef av_clip_int16
383 # define av_clip_int16 av_clip_int16_c
385 #ifndef av_clipl_int32
386 # define av_clipl_int32 av_clipl_int32_c
388 #ifndef av_clip_uintp2
389 # define av_clip_uintp2 av_clip_uintp2_c
392 # define av_sat_add32 av_sat_add32_c
394 #ifndef av_sat_dadd32
395 # define av_sat_dadd32 av_sat_dadd32_c
398 # define av_clipf av_clipf_c
401 # define av_popcount av_popcount_c
403 #ifndef av_popcount64
404 # define av_popcount64 av_popcount64_c