/********************************************************************
* *
* THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. *
- * USE, DISTRIBUTION AND REPRODUCTION OF THIS SOURCE IS GOVERNED BY *
- * THE GNU LESSER/LIBRARY PUBLIC LICENSE, WHICH IS INCLUDED WITH *
- * THIS SOURCE. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
+ * 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 1994-2000 *
- * by Monty <monty@xiph.org> and the XIPHOPHORUS Company *
- * http://www.xiph.org/ *
+ * 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
- last mod: $Id: scales.h,v 1.11 2001/01/22 01:38:26 xiphmont Exp $
********************************************************************/
-#ifndef _V_SCALE_H_
+#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 DYNAMIC_RANGE_dB 200.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)
+#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
#define fromOC(o) (exp(((o)+5.965784f)*.693147f))
#endif
-