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| author | Michael Niedermayer <michaelni@gmx.at> | 2012-10-12 14:26:46 +0200 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2012-10-12 14:26:46 +0200 |
| commit | e335658370840390272b70de92f5a76860537fb9 (patch) | |
| tree | 8f9074bfd2d0f5c6c09c34f23b354ee9dbce7e56 /libavcodec/mathops.h | |
| parent | 43cce41267a7aa71946911e87b4dfce48183bb25 (diff) | |
| parent | 9734b8ba56d05e970c353dfd5baafa43fdb08024 (diff) | |
| download | ffmpeg-e335658370840390272b70de92f5a76860537fb9.tar.gz | |
Merge commit '9734b8ba56d05e970c353dfd5baafa43fdb08024'
* commit '9734b8ba56d05e970c353dfd5baafa43fdb08024':
Move avutil tables only used in libavcodec to libavcodec.
Conflicts:
libavcodec/mathtables.c
libavutil/intmath.h
Merged-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavcodec/mathops.h')
| -rw-r--r-- | libavcodec/mathops.h | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/libavcodec/mathops.h b/libavcodec/mathops.h index 2840735c79..7ff055141d 100644 --- a/libavcodec/mathops.h +++ b/libavcodec/mathops.h @@ -22,9 +22,14 @@ #ifndef AVCODEC_MATHOPS_H #define AVCODEC_MATHOPS_H +#include <stdint.h> + #include "libavutil/common.h" #include "config.h" +extern const uint32_t ff_inverse[257]; +extern const uint8_t ff_sqrt_tab[256]; + #if ARCH_ARM # include "arm/mathops.h" #elif ARCH_AVR32 @@ -185,4 +190,28 @@ if ((y) < (x)) {\ # define PACK_2S16(a,b) PACK_2U16((a)&0xffff, (b)&0xffff) #endif +#ifndef FASTDIV +# define FASTDIV(a,b) ((uint32_t)((((uint64_t)a) * ff_inverse[b]) >> 32)) +#endif /* FASTDIV */ + +static inline av_const unsigned int ff_sqrt(unsigned int a) +{ + unsigned int b; + + if (a < 255) return (ff_sqrt_tab[a + 1] - 1) >> 4; + else if (a < (1 << 12)) b = ff_sqrt_tab[a >> 4] >> 2; +#if !CONFIG_SMALL + else if (a < (1 << 14)) b = ff_sqrt_tab[a >> 6] >> 1; + else if (a < (1 << 16)) b = ff_sqrt_tab[a >> 8] ; +#endif + else { + int s = av_log2_16bit(a >> 16) >> 1; + unsigned int c = a >> (s + 2); + b = ff_sqrt_tab[c >> (s + 8)]; + b = FASTDIV(c,b) + (b << s); + } + + return b - (a < b * b); +} + #endif /* AVCODEC_MATHOPS_H */ |