1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/libavutil/common.h	Tue Sep 25 15:55:33 2012 +0200
     1.3 @@ -0,0 +1,298 @@
     1.4 +/*
     1.5 + * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
     1.6 + *
     1.7 + * This file is part of FFmpeg.
     1.8 + *
     1.9 + * FFmpeg is free software; you can redistribute it and/or
    1.10 + * modify it under the terms of the GNU Lesser General Public
    1.11 + * License as published by the Free Software Foundation; either
    1.12 + * version 2.1 of the License, or (at your option) any later version.
    1.13 + *
    1.14 + * FFmpeg is distributed in the hope that it will be useful,
    1.15 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.16 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    1.17 + * Lesser General Public License for more details.
    1.18 + *
    1.19 + * You should have received a copy of the GNU Lesser General Public
    1.20 + * License along with FFmpeg; if not, write to the Free Software
    1.21 + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
    1.22 + */
    1.23 +
    1.24 +/**
    1.25 + * @file
    1.26 + * common internal and external API header
    1.27 + */
    1.28 +
    1.29 +#ifndef AVUTIL_COMMON_H
    1.30 +#define AVUTIL_COMMON_H
    1.31 +
    1.32 +#include <ctype.h>
    1.33 +#include <errno.h>
    1.34 +#include <inttypes.h>
    1.35 +#include <limits.h>
    1.36 +#include <math.h>
    1.37 +#include <stdio.h>
    1.38 +#include <stdlib.h>
    1.39 +#include <string.h>
    1.40 +#include "attributes.h"
    1.41 +
    1.42 +//rounded division & shift
    1.43 +#define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
    1.44 +/* assume b>0 */
    1.45 +#define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
    1.46 +#define FFABS(a) ((a) >= 0 ? (a) : (-(a)))
    1.47 +#define FFSIGN(a) ((a) > 0 ? 1 : -1)
    1.48 +
    1.49 +#define FFMAX(a,b) ((a) > (b) ? (a) : (b))
    1.50 +#define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c)
    1.51 +#define FFMIN(a,b) ((a) > (b) ? (b) : (a))
    1.52 +#define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c)
    1.53 +
    1.54 +#define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
    1.55 +#define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))
    1.56 +#define FFALIGN(x, a) (((x)+(a)-1)&~((a)-1))
    1.57 +
    1.58 +/* misc math functions */
    1.59 +extern const uint8_t ff_log2_tab[256];
    1.60 +
    1.61 +static inline av_const int av_log2_c(unsigned int v)
    1.62 +{
    1.63 +    int n = 0;
    1.64 +    if (v & 0xffff0000) {
    1.65 +        v >>= 16;
    1.66 +        n += 16;
    1.67 +    }
    1.68 +    if (v & 0xff00) {
    1.69 +        v >>= 8;
    1.70 +        n += 8;
    1.71 +    }
    1.72 +    n += ff_log2_tab[v];
    1.73 +
    1.74 +    return n;
    1.75 +}
    1.76 +
    1.77 +static inline av_const int av_log2_16bit_c(unsigned int v)
    1.78 +{
    1.79 +    int n = 0;
    1.80 +    if (v & 0xff00) {
    1.81 +        v >>= 8;
    1.82 +        n += 8;
    1.83 +    }
    1.84 +    n += ff_log2_tab[v];
    1.85 +
    1.86 +    return n;
    1.87 +}
    1.88 +
    1.89 +#ifdef HAVE_AV_CONFIG_H
    1.90 +#   include "config.h"
    1.91 +#endif
    1.92 +
    1.93 +/**
    1.94 + * Clips a signed integer value into the amin-amax range.
    1.95 + * @param a value to clip
    1.96 + * @param amin minimum value of the clip range
    1.97 + * @param amax maximum value of the clip range
    1.98 + * @return clipped value
    1.99 + */
   1.100 +static inline av_const int av_clip(int a, int amin, int amax)
   1.101 +{
   1.102 +    if      (a < amin) return amin;
   1.103 +    else if (a > amax) return amax;
   1.104 +    else               return a;
   1.105 +}
   1.106 +
   1.107 +/**
   1.108 + * Clips a signed integer value into the 0-255 range.
   1.109 + * @param a value to clip
   1.110 + * @return clipped value
   1.111 + */
   1.112 +static inline av_const uint8_t av_clip_uint8(int a)
   1.113 +{
   1.114 +    if (a&(~0xFF)) return (-a)>>31;
   1.115 +    else           return a;
   1.116 +}
   1.117 +
   1.118 +/**
   1.119 + * Clips a signed integer value into the 0-65535 range.
   1.120 + * @param a value to clip
   1.121 + * @return clipped value
   1.122 + */
   1.123 +static inline av_const uint16_t av_clip_uint16(int a)
   1.124 +{
   1.125 +    if (a&(~0xFFFF)) return (-a)>>31;
   1.126 +    else             return a;
   1.127 +}
   1.128 +
   1.129 +/**
   1.130 + * Clips a signed integer value into the -32768,32767 range.
   1.131 + * @param a value to clip
   1.132 + * @return clipped value
   1.133 + */
   1.134 +static inline av_const int16_t av_clip_int16(int a)
   1.135 +{
   1.136 +    if ((a+0x8000) & ~0xFFFF) return (a>>31) ^ 0x7FFF;
   1.137 +    else                      return a;
   1.138 +}
   1.139 +
   1.140 +/**
   1.141 + * Clips a signed 64-bit integer value into the -2147483648,2147483647 range.
   1.142 + * @param a value to clip
   1.143 + * @return clipped value
   1.144 + */
   1.145 +static inline av_const int32_t av_clipl_int32(int64_t a)
   1.146 +{
   1.147 +    if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (a>>63) ^ 0x7FFFFFFF;
   1.148 +    else                                         return a;
   1.149 +}
   1.150 +
   1.151 +/**
   1.152 + * Clips a float value into the amin-amax range.
   1.153 + * @param a value to clip
   1.154 + * @param amin minimum value of the clip range
   1.155 + * @param amax maximum value of the clip range
   1.156 + * @return clipped value
   1.157 + */
   1.158 +static inline av_const float av_clipf(float a, float amin, float amax)
   1.159 +{
   1.160 +    if      (a < amin) return amin;
   1.161 +    else if (a > amax) return amax;
   1.162 +    else               return a;
   1.163 +}
   1.164 +
   1.165 +/** Computes ceil(log2(x)).
   1.166 + * @param x value used to compute ceil(log2(x))
   1.167 + * @return computed ceiling of log2(x)
   1.168 + */
   1.169 +static inline av_const int av_ceil_log2(int x)
   1.170 +{
   1.171 +    return av_log2_c((x - 1) << 1);
   1.172 +}
   1.173 +
   1.174 +#define MKTAG(a,b,c,d) (a | (b << 8) | (c << 16) | (d << 24))
   1.175 +#define MKBETAG(a,b,c,d) (d | (c << 8) | (b << 16) | (a << 24))
   1.176 +
   1.177 +/*!
   1.178 + * \def GET_UTF8(val, GET_BYTE, ERROR)
   1.179 + * Converts a UTF-8 character (up to 4 bytes long) to its 32-bit UCS-4 encoded form
   1.180 + * \param val is the output and should be of type uint32_t. It holds the converted
   1.181 + * UCS-4 character and should be a left value.
   1.182 + * \param GET_BYTE gets UTF-8 encoded bytes from any proper source. It can be
   1.183 + * a function or a statement whose return value or evaluated value is of type
   1.184 + * uint8_t. It will be executed up to 4 times for values in the valid UTF-8 range,
   1.185 + * and up to 7 times in the general case.
   1.186 + * \param ERROR action that should be taken when an invalid UTF-8 byte is returned
   1.187 + * from GET_BYTE. It should be a statement that jumps out of the macro,
   1.188 + * like exit(), goto, return, break, or continue.
   1.189 + */
   1.190 +#define GET_UTF8(val, GET_BYTE, ERROR)\
   1.191 +    val= GET_BYTE;\
   1.192 +    {\
   1.193 +        int ones= 7 - av_log2(val ^ 255);\
   1.194 +        if(ones==1)\
   1.195 +            ERROR\
   1.196 +        val&= 127>>ones;\
   1.197 +        while(--ones > 0){\
   1.198 +            int tmp= GET_BYTE - 128;\
   1.199 +            if(tmp>>6)\
   1.200 +                ERROR\
   1.201 +            val= (val<<6) + tmp;\
   1.202 +        }\
   1.203 +    }
   1.204 +
   1.205 +/*!
   1.206 + * \def GET_UTF16(val, GET_16BIT, ERROR)
   1.207 + * Converts a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form
   1.208 + * \param val is the output and should be of type uint32_t. It holds the converted
   1.209 + * UCS-4 character and should be a left value.
   1.210 + * \param GET_16BIT gets two bytes of UTF-16 encoded data converted to native endianness.
   1.211 + * It can be a function or a statement whose return value or evaluated value is of type
   1.212 + * uint16_t. It will be executed up to 2 times.
   1.213 + * \param ERROR action that should be taken when an invalid UTF-16 surrogate is
   1.214 + * returned from GET_BYTE. It should be a statement that jumps out of the macro,
   1.215 + * like exit(), goto, return, break, or continue.
   1.216 + */
   1.217 +#define GET_UTF16(val, GET_16BIT, ERROR)\
   1.218 +    val = GET_16BIT;\
   1.219 +    {\
   1.220 +        unsigned int hi = val - 0xD800;\
   1.221 +        if (hi < 0x800) {\
   1.222 +            val = GET_16BIT - 0xDC00;\
   1.223 +            if (val > 0x3FFU || hi > 0x3FFU)\
   1.224 +                ERROR\
   1.225 +            val += (hi<<10) + 0x10000;\
   1.226 +        }\
   1.227 +    }\
   1.228 +
   1.229 +/*!
   1.230 + * \def PUT_UTF8(val, tmp, PUT_BYTE)
   1.231 + * Converts a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).
   1.232 + * \param val is an input-only argument and should be of type uint32_t. It holds
   1.233 + * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If
   1.234 + * val is given as a function it is executed only once.
   1.235 + * \param tmp is a temporary variable and should be of type uint8_t. It
   1.236 + * represents an intermediate value during conversion that is to be
   1.237 + * output by PUT_BYTE.
   1.238 + * \param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
   1.239 + * It could be a function or a statement, and uses tmp as the input byte.
   1.240 + * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
   1.241 + * executed up to 4 times for values in the valid UTF-8 range and up to
   1.242 + * 7 times in the general case, depending on the length of the converted
   1.243 + * Unicode character.
   1.244 + */
   1.245 +#define PUT_UTF8(val, tmp, PUT_BYTE)\
   1.246 +    {\
   1.247 +        int bytes, shift;\
   1.248 +        uint32_t in = val;\
   1.249 +        if (in < 0x80) {\
   1.250 +            tmp = in;\
   1.251 +            PUT_BYTE\
   1.252 +        } else {\
   1.253 +            bytes = (av_log2(in) + 4) / 5;\
   1.254 +            shift = (bytes - 1) * 6;\
   1.255 +            tmp = (256 - (256 >> bytes)) | (in >> shift);\
   1.256 +            PUT_BYTE\
   1.257 +            while (shift >= 6) {\
   1.258 +                shift -= 6;\
   1.259 +                tmp = 0x80 | ((in >> shift) & 0x3f);\
   1.260 +                PUT_BYTE\
   1.261 +            }\
   1.262 +        }\
   1.263 +    }
   1.264 +
   1.265 +/*!
   1.266 + * \def PUT_UTF16(val, tmp, PUT_16BIT)
   1.267 + * Converts a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes).
   1.268 + * \param val is an input-only argument and should be of type uint32_t. It holds
   1.269 + * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If
   1.270 + * val is given as a function it is executed only once.
   1.271 + * \param tmp is a temporary variable and should be of type uint16_t. It
   1.272 + * represents an intermediate value during conversion that is to be
   1.273 + * output by PUT_16BIT.
   1.274 + * \param PUT_16BIT writes the converted UTF-16 data to any proper destination
   1.275 + * in desired endianness. It could be a function or a statement, and uses tmp
   1.276 + * as the input byte.  For example, PUT_BYTE could be "*output++ = tmp;"
   1.277 + * PUT_BYTE will be executed 1 or 2 times depending on input character.
   1.278 + */
   1.279 +#define PUT_UTF16(val, tmp, PUT_16BIT)\
   1.280 +    {\
   1.281 +        uint32_t in = val;\
   1.282 +        if (in < 0x10000) {\
   1.283 +            tmp = in;\
   1.284 +            PUT_16BIT\
   1.285 +        } else {\
   1.286 +            tmp = 0xD800 | ((in - 0x10000) >> 10);\
   1.287 +            PUT_16BIT\
   1.288 +            tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\
   1.289 +            PUT_16BIT\
   1.290 +        }\
   1.291 +    }\
   1.292 +
   1.293 +
   1.294 +
   1.295 +#include "mem.h"
   1.296 +
   1.297 +#ifdef HAVE_AV_CONFIG_H
   1.298 +#    include "internal.h"
   1.299 +#endif /* HAVE_AV_CONFIG_H */
   1.300 +
   1.301 +#endif /* AVUTIL_COMMON_H */