1 /********************************************************************
3 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. *
4 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
5 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
6 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
8 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2001 *
9 * by the XIPHOPHORUS Company http://www.xiph.org/ *
11 ********************************************************************
13 function: linear scale -> dB, Bark and Mel scales
14 last mod: $Id: scales.h,v 1.21 2002/03/17 19:50:47 xiphmont Exp $
16 ********************************************************************/
25 #ifdef VORBIS_IEEE_FLOAT32
27 static float unitnorm(float x){
28 ogg_uint32_t *ix=(ogg_uint32_t *)&x;
29 *ix=(*ix&0x80000000UL)|(0x3f800000UL);
33 static float FABS(float x){
34 ogg_uint32_t *ix=(ogg_uint32_t *)&x;
39 static float todB_LOOKUP[256]={
40 -140.277330f, -139.633636f, -139.034372f, -138.473797f,
41 -137.450747f, -136.535597f, -135.707743f, -134.951972f,
42 -134.256730f, -133.613036f, -133.013772f, -132.453198f,
43 -131.430147f, -130.514997f, -129.687144f, -128.931372f,
44 -128.236130f, -127.592437f, -126.993172f, -126.432598f,
45 -125.409547f, -124.494397f, -123.666544f, -122.910772f,
46 -122.215530f, -121.571837f, -120.972572f, -120.411998f,
47 -119.388947f, -118.473797f, -117.645944f, -116.890173f,
48 -116.194930f, -115.551237f, -114.951972f, -114.391398f,
49 -113.368347f, -112.453198f, -111.625344f, -110.869573f,
50 -110.174331f, -109.530637f, -108.931372f, -108.370798f,
51 -107.347748f, -106.432598f, -105.604744f, -104.848973f,
52 -104.153731f, -103.510037f, -102.910773f, -102.350198f,
53 -101.327148f, -100.411998f, -99.584144f, -98.828373f,
54 -98.133131f, -97.489437f, -96.890173f, -96.329598f,
55 -95.306548f, -94.391398f, -93.563544f, -92.807773f,
56 -92.112531f, -91.468837f, -90.869573f, -90.308998f,
57 -89.285948f, -88.370798f, -87.542944f, -86.787173f,
58 -86.091931f, -85.448237f, -84.848973f, -84.288398f,
59 -83.265348f, -82.350198f, -81.522344f, -80.766573f,
60 -80.071331f, -79.427637f, -78.828373f, -78.267799f,
61 -77.244748f, -76.329598f, -75.501745f, -74.745973f,
62 -74.050731f, -73.407038f, -72.807773f, -72.247199f,
63 -71.224148f, -70.308998f, -69.481145f, -68.725373f,
64 -68.030131f, -67.386438f, -66.787173f, -66.226599f,
65 -65.203548f, -64.288399f, -63.460545f, -62.704774f,
66 -62.009531f, -61.365838f, -60.766573f, -60.205999f,
67 -59.182948f, -58.267799f, -57.439945f, -56.684174f,
68 -55.988932f, -55.345238f, -54.745973f, -54.185399f,
69 -53.162349f, -52.247199f, -51.419345f, -50.663574f,
70 -49.968332f, -49.324638f, -48.725374f, -48.164799f,
71 -47.141749f, -46.226599f, -45.398745f, -44.642974f,
72 -43.947732f, -43.304038f, -42.704774f, -42.144199f,
73 -41.121149f, -40.205999f, -39.378145f, -38.622374f,
74 -37.927132f, -37.283438f, -36.684174f, -36.123599f,
75 -35.100549f, -34.185399f, -33.357545f, -32.601774f,
76 -31.906532f, -31.262838f, -30.663574f, -30.102999f,
77 -29.079949f, -28.164799f, -27.336945f, -26.581174f,
78 -25.885932f, -25.242238f, -24.642974f, -24.082400f,
79 -23.059349f, -22.144199f, -21.316346f, -20.560574f,
80 -19.865332f, -19.221639f, -18.622374f, -18.061800f,
81 -17.038749f, -16.123599f, -15.295746f, -14.539974f,
82 -13.844732f, -13.201039f, -12.601774f, -12.041200f,
83 -11.018149f, -10.103000f, -9.275146f, -8.519375f,
84 -7.824132f, -7.180439f, -6.581174f, -6.020600f,
85 -4.997549f, -4.082400f, -3.254546f, -2.498775f,
86 -1.803533f, -1.159839f, -0.560574f, 0.000000f,
87 1.023050f, 1.938200f, 2.766054f, 3.521825f,
88 4.217067f, 4.860761f, 5.460025f, 6.020600f,
89 7.043650f, 7.958800f, 8.786654f, 9.542425f,
90 10.237667f, 10.881361f, 11.480625f, 12.041200f,
91 13.064250f, 13.979400f, 14.807254f, 15.563025f,
92 16.258267f, 16.901961f, 17.501225f, 18.061800f,
93 19.084850f, 20.000000f, 20.827854f, 21.583625f,
94 22.278867f, 22.922561f, 23.521825f, 24.082400f,
95 25.105450f, 26.020600f, 26.848453f, 27.604225f,
96 28.299467f, 28.943161f, 29.542425f, 30.102999f,
97 31.126050f, 32.041200f, 32.869053f, 33.624825f,
98 34.320067f, 34.963760f, 35.563025f, 36.123599f,
99 37.146650f, 38.061800f, 38.889653f, 39.645424f,
100 40.340667f, 40.984360f, 41.583625f, 42.144199f,
101 43.167250f, 44.082399f, 44.910253f, 45.666024f,
102 46.361266f, 47.004960f, 47.604225f, 48.164799f,
103 49.187850f, 50.102999f, 50.930853f, 51.686624f
106 static float todB(const float *x){
107 ogg_int32_t *i=(ogg_int32_t *)x;
108 ogg_int32_t temp=((*i&0x7fffffff)-0x33c7ffff)>>20;
109 if(temp<0)return -400.f;
110 return(todB_LOOKUP[temp]);
113 #define todB_nn(x) todB(x)
117 static float unitnorm(float x){
122 #define FABS(x) fabs(*(x))
124 #define todB(x) (*(x)==0?-400.f:log(*(x)**(x))*4.34294480f)
125 #define todB_nn(x) (*(x)==0.f?-400.f:log(*(x))*8.6858896f)
129 #define fromdB(x) (exp((x)*.11512925f))
131 /* The bark scale equations are approximations, since the original
132 table was somewhat hand rolled. The below are chosen to have the
133 best possible fit to the rolled tables, thus their somewhat odd
134 appearance (these are more accurate and over a longer range than
135 the oft-quoted bark equations found in the texts I have). The
136 approximations are valid from 0 - 30kHz (nyquist) or so.
138 all f in Hz, z in Bark */
140 #define toBARK(n) (13.1f*atan(.00074f*(n))+2.24f*atan((n)*(n)*1.85e-8f)+1e-4f*(n))
141 #define fromBARK(z) (102.f*(z)-2.f*pow(z,2.f)+.4f*pow(z,3.f)+pow(1.46f,z)-1.f)
142 #define toMEL(n) (log(1.f+(n)*.001f)*1442.695f)
143 #define fromMEL(m) (1000.f*exp((m)/1442.695f)-1000.f)
145 /* Frequency to octave. We arbitrarily declare 63.5 Hz to be octave
148 #define toOC(n) (log(n)*1.442695f-5.965784f)
149 #define fromOC(o) (exp(((o)+5.965784f)*.693147f))