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- /*
- * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
- *
- * This file is part of FFmpeg.
- *
- * FFmpeg is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * FFmpeg is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
- /**
- * @file libavutil/common.h
- * common internal and external API header
- */
-
- #ifndef AVUTIL_COMMON_H
- #define AVUTIL_COMMON_H
-
- #include <ctype.h>
- #include <errno.h>
- #include <inttypes.h>
- #include <limits.h>
- #include <math.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
-
- #ifdef __GNUC__
- # define AV_GCC_VERSION_AT_LEAST(x,y) (__GNUC__ > x || __GNUC__ == x && __GNUC_MINOR__ >= y)
- #else
- # define AV_GCC_VERSION_AT_LEAST(x,y) 0
- #endif
-
- #ifndef av_always_inline
- #if AV_GCC_VERSION_AT_LEAST(3,1)
- # define av_always_inline __attribute__((always_inline)) inline
- #else
- # define av_always_inline inline
- #endif
- #endif
-
- #ifndef av_noinline
- #if AV_GCC_VERSION_AT_LEAST(3,1)
- # define av_noinline __attribute__((noinline))
- #else
- # define av_noinline
- #endif
- #endif
-
- #ifndef av_pure
- #if AV_GCC_VERSION_AT_LEAST(3,1)
- # define av_pure __attribute__((pure))
- #else
- # define av_pure
- #endif
- #endif
-
- #ifndef av_const
- #if AV_GCC_VERSION_AT_LEAST(2,6)
- # define av_const __attribute__((const))
- #else
- # define av_const
- #endif
- #endif
-
- #ifndef av_cold
- #if (!defined(__ICC) || __ICC > 1100) && AV_GCC_VERSION_AT_LEAST(4,3)
- # define av_cold __attribute__((cold))
- #else
- # define av_cold
- #endif
- #endif
-
- #ifndef av_flatten
- #if AV_GCC_VERSION_AT_LEAST(4,1)
- # define av_flatten __attribute__((flatten))
- #else
- # define av_flatten
- #endif
- #endif
-
- #ifndef attribute_deprecated
- #if AV_GCC_VERSION_AT_LEAST(3,1)
- # define attribute_deprecated __attribute__((deprecated))
- #else
- # define attribute_deprecated
- #endif
- #endif
-
- #ifndef av_unused
- #if defined(__GNUC__)
- # define av_unused __attribute__((unused))
- #else
- # define av_unused
- #endif
- #endif
-
- #ifndef av_uninit
- #if defined(__GNUC__) && !defined(__ICC)
- # define av_uninit(x) x=x
- #else
- # define av_uninit(x) x
- #endif
- #endif
-
- //rounded division & shift
- #define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
- /* assume b>0 */
- #define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
- #define FFABS(a) ((a) >= 0 ? (a) : (-(a)))
- #define FFSIGN(a) ((a) > 0 ? 1 : -1)
-
- #define FFMAX(a,b) ((a) > (b) ? (a) : (b))
- #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c)
- #define FFMIN(a,b) ((a) > (b) ? (b) : (a))
- #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c)
-
- #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
- #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))
-
- /* misc math functions */
- extern const uint8_t ff_log2_tab[256];
-
- __inline av_const int av_log2(unsigned int v)
- {
- int n = 0;
- if (v & 0xffff0000) {
- v >>= 16;
- n += 16;
- }
- if (v & 0xff00) {
- v >>= 8;
- n += 8;
- }
- n += ff_log2_tab[v];
-
- return n;
- }
-
- __inline av_const int av_log2_16bit(unsigned int v)
- {
- int n = 0;
- if (v & 0xff00) {
- v >>= 8;
- n += 8;
- }
- n += ff_log2_tab[v];
-
- return n;
- }
-
- /**
- * Clips a signed integer value into the amin-amax range.
- * @param a value to clip
- * @param amin minimum value of the clip range
- * @param amax maximum value of the clip range
- * @return clipped value
- */
- __inline av_const int av_clip(int a, int amin, int amax)
- {
- if (a < amin) return amin;
- else if (a > amax) return amax;
- else return a;
- }
-
- /**
- * Clips a signed integer value into the 0-255 range.
- * @param a value to clip
- * @return clipped value
- */
- __inline av_const uint8_t av_clip_uint8(int a)
- {
- if (a&(~255)) return (-a)>>31;
- else return a;
- }
-
- /**
- * Clips a signed integer value into the -32768,32767 range.
- * @param a value to clip
- * @return clipped value
- */
- __inline av_const int16_t av_clip_int16(int a)
- {
- if ((a+32768) & ~65535) return (a>>31) ^ 32767;
- else return a;
- }
-
- /**
- * Clips a float value into the amin-amax range.
- * @param a value to clip
- * @param amin minimum value of the clip range
- * @param amax maximum value of the clip range
- * @return clipped value
- */
- __inline av_const float av_clipf(float a, float amin, float amax)
- {
- if (a < amin) return amin;
- else if (a > amax) return amax;
- else return a;
- }
-
- #define MKTAG(a,b,c,d) (a | (b << 8) | (c << 16) | (d << 24))
- #define MKBETAG(a,b,c,d) (d | (c << 8) | (b << 16) | (a << 24))
-
- /*!
- * \def GET_UTF8(val, GET_BYTE, ERROR)
- * Converts a UTF-8 character (up to 4 bytes long) to its 32-bit UCS-4 encoded form
- * \param val is the output and should be of type uint32_t. It holds the converted
- * UCS-4 character and should be a left value.
- * \param GET_BYTE gets UTF-8 encoded bytes from any proper source. It can be
- * a function or a statement whose return value or evaluated value is of type
- * uint8_t. It will be executed up to 4 times for values in the valid UTF-8 range,
- * and up to 7 times in the general case.
- * \param ERROR action that should be taken when an invalid UTF-8 byte is returned
- * from GET_BYTE. It should be a statement that jumps out of the macro,
- * like exit(), goto, return, break, or continue.
- */
- #define GET_UTF8(val, GET_BYTE, ERROR)\
- val= GET_BYTE;\
- {\
- int ones= 7 - av_log2(val ^ 255);\
- if(ones==1)\
- ERROR\
- val&= 127>>ones;\
- while(--ones > 0){\
- int tmp= GET_BYTE - 128;\
- if(tmp>>6)\
- ERROR\
- val= (val<<6) + tmp;\
- }\
- }
-
- /*!
- * \def PUT_UTF8(val, tmp, PUT_BYTE)
- * Converts a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).
- * \param val is an input-only argument and should be of type uint32_t. It holds
- * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If
- * val is given as a function it is executed only once.
- * \param tmp is a temporary variable and should be of type uint8_t. It
- * represents an intermediate value during conversion that is to be
- * output by PUT_BYTE.
- * \param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
- * It could be a function or a statement, and uses tmp as the input byte.
- * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
- * executed up to 4 times for values in the valid UTF-8 range and up to
- * 7 times in the general case, depending on the length of the converted
- * Unicode character.
- */
- #define PUT_UTF8(val, tmp, PUT_BYTE)\
- {\
- int bytes, shift;\
- uint32_t in = val;\
- if (in < 0x80) {\
- tmp = in;\
- PUT_BYTE\
- } else {\
- bytes = (av_log2(in) + 4) / 5;\
- shift = (bytes - 1) * 6;\
- tmp = (256 - (256 >> bytes)) | (in >> shift);\
- PUT_BYTE\
- while (shift >= 6) {\
- shift -= 6;\
- tmp = 0x80 | ((in >> shift) & 0x3f);\
- PUT_BYTE\
- }\
- }\
- }
-
- #include "mem.h"
-
- #ifdef HAVE_AV_CONFIG_H
- # include "config.h"
- # include "internal.h"
- #endif /* HAVE_AV_CONFIG_H */
-
- #endif /* AVUTIL_COMMON_H */
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