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d9a291f641
Took the opportunity to undo the Godot changed made to the opus source. The opus module should eventually be built in its own environment to avoid polluting others with too many include dirs and defines. TODO: Fix the platform/ stuff for opus.
95 lines
3.2 KiB
C
95 lines
3.2 KiB
C
/********************************************************************
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* *
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* THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. *
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* USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
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* GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
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* IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
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* *
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* THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009 *
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* by the Xiph.Org Foundation http://www.xiph.org/ *
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* *
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********************************************************************
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function: lookup based functions
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last mod: $Id: lookup.c 16227 2009-07-08 06:58:46Z xiphmont $
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********************************************************************/
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#include <math.h>
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#include "lookup.h"
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#include "lookup_data.h"
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#include "os.h"
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#include "misc.h"
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#ifdef FLOAT_LOOKUP
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/* interpolated lookup based cos function, domain 0 to PI only */
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float vorbis_coslook(float a){
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double d=a*(.31830989*(float)COS_LOOKUP_SZ);
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int i=vorbis_ftoi(d-.5);
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return COS_LOOKUP[i]+ (d-i)*(COS_LOOKUP[i+1]-COS_LOOKUP[i]);
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}
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/* interpolated 1./sqrt(p) where .5 <= p < 1. */
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float vorbis_invsqlook(float a){
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double d=a*(2.f*(float)INVSQ_LOOKUP_SZ)-(float)INVSQ_LOOKUP_SZ;
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int i=vorbis_ftoi(d-.5f);
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return INVSQ_LOOKUP[i]+ (d-i)*(INVSQ_LOOKUP[i+1]-INVSQ_LOOKUP[i]);
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}
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/* interpolated 1./sqrt(p) where .5 <= p < 1. */
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float vorbis_invsq2explook(int a){
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return INVSQ2EXP_LOOKUP[a-INVSQ2EXP_LOOKUP_MIN];
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}
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#include <stdio.h>
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/* interpolated lookup based fromdB function, domain -140dB to 0dB only */
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float vorbis_fromdBlook(float a){
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int i=vorbis_ftoi(a*((float)(-(1<<FROMdB2_SHIFT)))-.5f);
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return (i<0)?1.f:
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((i>=(FROMdB_LOOKUP_SZ<<FROMdB_SHIFT))?0.f:
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FROMdB_LOOKUP[i>>FROMdB_SHIFT]*FROMdB2_LOOKUP[i&FROMdB2_MASK]);
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}
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#endif
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#ifdef INT_LOOKUP
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/* interpolated 1./sqrt(p) where .5 <= a < 1. (.100000... to .111111...) in
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16.16 format
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returns in m.8 format */
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long vorbis_invsqlook_i(long a,long e){
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long i=(a&0x7fff)>>(INVSQ_LOOKUP_I_SHIFT-1);
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long d=(a&INVSQ_LOOKUP_I_MASK)<<(16-INVSQ_LOOKUP_I_SHIFT); /* 0.16 */
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long val=INVSQ_LOOKUP_I[i]- /* 1.16 */
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(((INVSQ_LOOKUP_I[i]-INVSQ_LOOKUP_I[i+1])* /* 0.16 */
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d)>>16); /* result 1.16 */
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e+=32;
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if(e&1)val=(val*5792)>>13; /* multiply val by 1/sqrt(2) */
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e=(e>>1)-8;
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return(val>>e);
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}
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/* interpolated lookup based fromdB function, domain -140dB to 0dB only */
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/* a is in n.12 format */
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float vorbis_fromdBlook_i(long a){
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int i=(-a)>>(12-FROMdB2_SHIFT);
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return (i<0)?1.f:
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((i>=(FROMdB_LOOKUP_SZ<<FROMdB_SHIFT))?0.f:
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FROMdB_LOOKUP[i>>FROMdB_SHIFT]*FROMdB2_LOOKUP[i&FROMdB2_MASK]);
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}
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/* interpolated lookup based cos function, domain 0 to PI only */
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/* a is in 0.16 format, where 0==0, 2^^16-1==PI, return 0.14 */
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long vorbis_coslook_i(long a){
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int i=a>>COS_LOOKUP_I_SHIFT;
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int d=a&COS_LOOKUP_I_MASK;
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return COS_LOOKUP_I[i]- ((d*(COS_LOOKUP_I[i]-COS_LOOKUP_I[i+1]))>>
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COS_LOOKUP_I_SHIFT);
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}
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#endif
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