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Diffstat (limited to 'vorbis/lib/scales.h')
-rw-r--r-- | vorbis/lib/scales.h | 89 |
1 files changed, 0 insertions, 89 deletions
diff --git a/vorbis/lib/scales.h b/vorbis/lib/scales.h deleted file mode 100644 index 18bc4e7..0000000 --- a/vorbis/lib/scales.h +++ /dev/null @@ -1,89 +0,0 @@ -/******************************************************************** - * * - * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. * - * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * - * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * - * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * - * * - * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009 * - * by the Xiph.Org Foundation http://www.xiph.org/ * - * * - ******************************************************************** - - function: linear scale -> dB, Bark and Mel scales - - ********************************************************************/ - -#ifndef _V_SCALES_H_ -#define _V_SCALES_H_ - -#include <math.h> -#include "os.h" - -#ifdef _MSC_VER -/* MS Visual Studio doesn't have C99 inline keyword. */ -#define inline __inline -#endif - -/* 20log10(x) */ -#define VORBIS_IEEE_FLOAT32 1 -#ifdef VORBIS_IEEE_FLOAT32 - -static inline float unitnorm(float x){ - union { - ogg_uint32_t i; - float f; - } ix; - ix.f = x; - ix.i = (ix.i & 0x80000000U) | (0x3f800000U); - return ix.f; -} - -/* Segher was off (too high) by ~ .3 decibel. Center the conversion correctly. */ -static inline float todB(const float *x){ - union { - ogg_uint32_t i; - float f; - } ix; - ix.f = *x; - ix.i = ix.i&0x7fffffff; - return (float)(ix.i * 7.17711438e-7f -764.6161886f); -} - -#define todB_nn(x) todB(x) - -#else - -static float unitnorm(float x){ - if(x<0)return(-1.f); - return(1.f); -} - -#define todB(x) (*(x)==0?-400.f:log(*(x)**(x))*4.34294480f) -#define todB_nn(x) (*(x)==0.f?-400.f:log(*(x))*8.6858896f) - -#endif - -#define fromdB(x) (exp((x)*.11512925f)) - -/* The bark scale equations are approximations, since the original - table was somewhat hand rolled. The below are chosen to have the - best possible fit to the rolled tables, thus their somewhat odd - appearance (these are more accurate and over a longer range than - the oft-quoted bark equations found in the texts I have). The - approximations are valid from 0 - 30kHz (nyquist) or so. - - all f in Hz, z in Bark */ - -#define toBARK(n) (13.1f*atan(.00074f*(n))+2.24f*atan((n)*(n)*1.85e-8f)+1e-4f*(n)) -#define fromBARK(z) (102.f*(z)-2.f*pow(z,2.f)+.4f*pow(z,3.f)+pow(1.46f,z)-1.f) -#define toMEL(n) (log(1.f+(n)*.001f)*1442.695f) -#define fromMEL(m) (1000.f*exp((m)/1442.695f)-1000.f) - -/* Frequency to octave. We arbitrarily declare 63.5 Hz to be octave - 0.0 */ - -#define toOC(n) (log(n)*1.442695f-5.965784f) -#define fromOC(o) (exp(((o)+5.965784f)*.693147f)) - -#endif |