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| author | Diego Biurrun <diego@biurrun.de> | 2012-10-11 01:16:05 +0200 |
|---|---|---|
| committer | Diego Biurrun <diego@biurrun.de> | 2012-10-11 18:29:36 +0200 |
| commit | 9734b8ba56d05e970c353dfd5baafa43fdb08024 (patch) | |
| tree | e1f40e82ce4aa2ab7dc081115278057e08ffbbb6 /libavcodec/mathops.h | |
| parent | 0a75d1da23b8659ec49391469bb592da12760077 (diff) | |
| download | ffmpeg-9734b8ba56d05e970c353dfd5baafa43fdb08024.tar.gz | |
Move avutil tables only used in libavcodec to libavcodec.
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 ab545ef504..218c459acc 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 */ |