228 lines
6.7 KiB
C
228 lines
6.7 KiB
C
/* Copyright (C) 2006 Jean-Marc Valin */
|
|
/**
|
|
@file filterbank.c
|
|
@brief Converting between psd and filterbank
|
|
*/
|
|
/*
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions are
|
|
met:
|
|
|
|
1. Redistributions of source code must retain the above copyright notice,
|
|
this list of conditions and the following disclaimer.
|
|
|
|
2. Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in the
|
|
documentation and/or other materials provided with the distribution.
|
|
|
|
3. The name of the author may not be used to endorse or promote products
|
|
derived from this software without specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
|
|
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
|
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
|
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
|
|
#include "config.h"
|
|
|
|
|
|
#include "filterbank.h"
|
|
#include "arch.h"
|
|
#include <math.h>
|
|
#include "math_approx.h"
|
|
#include "os_support.h"
|
|
|
|
#ifdef FIXED_POINT
|
|
|
|
#define toBARK(n) (MULT16_16(26829,spx_atan(SHR32(MULT16_16(97,n),2))) + MULT16_16(4588,spx_atan(MULT16_32_Q15(20,MULT16_16(n,n)))) + MULT16_16(3355,n))
|
|
|
|
#else
|
|
#define toBARK(n) (13.1f*atan(.00074f*(n))+2.24f*atan((n)*(n)*1.85e-8f)+1e-4f*(n))
|
|
#endif
|
|
|
|
#define toMEL(n) (2595.f*log10(1.f+(n)/700.f))
|
|
|
|
FilterBank *filterbank_new(int banks, spx_word32_t sampling, int len, int type)
|
|
{
|
|
FilterBank *bank;
|
|
spx_word32_t df;
|
|
spx_word32_t max_mel, mel_interval;
|
|
int i;
|
|
int id1;
|
|
int id2;
|
|
df = DIV32(SHL32(sampling,15),MULT16_16(2,len));
|
|
max_mel = toBARK(EXTRACT16(sampling/2));
|
|
mel_interval = PDIV32(max_mel,banks-1);
|
|
|
|
bank = (FilterBank*)speex_alloc(sizeof(FilterBank));
|
|
bank->nb_banks = banks;
|
|
bank->len = len;
|
|
bank->bank_left = (int*)speex_alloc(len*sizeof(int));
|
|
bank->bank_right = (int*)speex_alloc(len*sizeof(int));
|
|
bank->filter_left = (spx_word16_t*)speex_alloc(len*sizeof(spx_word16_t));
|
|
bank->filter_right = (spx_word16_t*)speex_alloc(len*sizeof(spx_word16_t));
|
|
/* Think I can safely disable normalisation that for fixed-point (and probably float as well) */
|
|
#ifndef FIXED_POINT
|
|
bank->scaling = (float*)speex_alloc(banks*sizeof(float));
|
|
#endif
|
|
for (i=0;i<len;i++)
|
|
{
|
|
spx_word16_t curr_freq;
|
|
spx_word32_t mel;
|
|
spx_word16_t val;
|
|
curr_freq = EXTRACT16(MULT16_32_P15(i,df));
|
|
mel = toBARK(curr_freq);
|
|
if (mel > max_mel)
|
|
break;
|
|
#ifdef FIXED_POINT
|
|
id1 = DIV32(mel,mel_interval);
|
|
#else
|
|
id1 = (int)(floor(mel/mel_interval));
|
|
#endif
|
|
if (id1>banks-2)
|
|
{
|
|
id1 = banks-2;
|
|
val = Q15_ONE;
|
|
} else {
|
|
val = DIV32_16(mel - id1*mel_interval,EXTRACT16(PSHR32(mel_interval,15)));
|
|
}
|
|
id2 = id1+1;
|
|
bank->bank_left[i] = id1;
|
|
bank->filter_left[i] = SUB16(Q15_ONE,val);
|
|
bank->bank_right[i] = id2;
|
|
bank->filter_right[i] = val;
|
|
}
|
|
|
|
/* Think I can safely disable normalisation for fixed-point (and probably float as well) */
|
|
#ifndef FIXED_POINT
|
|
for (i=0;i<bank->nb_banks;i++)
|
|
bank->scaling[i] = 0;
|
|
for (i=0;i<bank->len;i++)
|
|
{
|
|
int id = bank->bank_left[i];
|
|
bank->scaling[id] += bank->filter_left[i];
|
|
id = bank->bank_right[i];
|
|
bank->scaling[id] += bank->filter_right[i];
|
|
}
|
|
for (i=0;i<bank->nb_banks;i++)
|
|
bank->scaling[i] = Q15_ONE/(bank->scaling[i]);
|
|
#endif
|
|
return bank;
|
|
}
|
|
|
|
void filterbank_destroy(FilterBank *bank)
|
|
{
|
|
speex_free(bank->bank_left);
|
|
speex_free(bank->bank_right);
|
|
speex_free(bank->filter_left);
|
|
speex_free(bank->filter_right);
|
|
#ifndef FIXED_POINT
|
|
speex_free(bank->scaling);
|
|
#endif
|
|
speex_free(bank);
|
|
}
|
|
|
|
void filterbank_compute_bank32(FilterBank *bank, spx_word32_t *ps, spx_word32_t *mel)
|
|
{
|
|
int i;
|
|
for (i=0;i<bank->nb_banks;i++)
|
|
mel[i] = 0;
|
|
|
|
for (i=0;i<bank->len;i++)
|
|
{
|
|
int id;
|
|
id = bank->bank_left[i];
|
|
mel[id] += MULT16_32_P15(bank->filter_left[i],ps[i]);
|
|
id = bank->bank_right[i];
|
|
mel[id] += MULT16_32_P15(bank->filter_right[i],ps[i]);
|
|
}
|
|
/* Think I can safely disable normalisation that for fixed-point (and probably float as well) */
|
|
#ifndef FIXED_POINT
|
|
/*for (i=0;i<bank->nb_banks;i++)
|
|
mel[i] = MULT16_32_P15(Q15(bank->scaling[i]),mel[i]);
|
|
*/
|
|
#endif
|
|
}
|
|
|
|
void filterbank_compute_psd16(FilterBank *bank, spx_word16_t *mel, spx_word16_t *ps)
|
|
{
|
|
int i;
|
|
for (i=0;i<bank->len;i++)
|
|
{
|
|
spx_word32_t tmp;
|
|
int id1, id2;
|
|
id1 = bank->bank_left[i];
|
|
id2 = bank->bank_right[i];
|
|
tmp = MULT16_16(mel[id1],bank->filter_left[i]);
|
|
tmp += MULT16_16(mel[id2],bank->filter_right[i]);
|
|
ps[i] = EXTRACT16(PSHR32(tmp,15));
|
|
}
|
|
}
|
|
|
|
|
|
#ifndef FIXED_POINT
|
|
void filterbank_compute_bank(FilterBank *bank, float *ps, float *mel)
|
|
{
|
|
int i;
|
|
for (i=0;i<bank->nb_banks;i++)
|
|
mel[i] = 0;
|
|
|
|
for (i=0;i<bank->len;i++)
|
|
{
|
|
int id = bank->bank_left[i];
|
|
mel[id] += bank->filter_left[i]*ps[i];
|
|
id = bank->bank_right[i];
|
|
mel[id] += bank->filter_right[i]*ps[i];
|
|
}
|
|
for (i=0;i<bank->nb_banks;i++)
|
|
mel[i] *= bank->scaling[i];
|
|
}
|
|
|
|
void filterbank_compute_psd(FilterBank *bank, float *mel, float *ps)
|
|
{
|
|
int i;
|
|
for (i=0;i<bank->len;i++)
|
|
{
|
|
int id = bank->bank_left[i];
|
|
ps[i] = mel[id]*bank->filter_left[i];
|
|
id = bank->bank_right[i];
|
|
ps[i] += mel[id]*bank->filter_right[i];
|
|
}
|
|
}
|
|
|
|
void filterbank_psy_smooth(FilterBank *bank, float *ps, float *mask)
|
|
{
|
|
/* Low freq slope: 14 dB/Bark*/
|
|
/* High freq slope: 9 dB/Bark*/
|
|
/* Noise vs tone: 5 dB difference */
|
|
/* FIXME: Temporary kludge */
|
|
float bark[100];
|
|
int i;
|
|
/* Assumes 1/3 Bark resolution */
|
|
float decay_low = 0.34145f;
|
|
float decay_high = 0.50119f;
|
|
filterbank_compute_bank(bank, ps, bark);
|
|
for (i=1;i<bank->nb_banks;i++)
|
|
{
|
|
/*float decay_high = 13-1.6*log10(bark[i-1]);
|
|
decay_high = pow(10,(-decay_high/30.f));*/
|
|
bark[i] = bark[i] + decay_high*bark[i-1];
|
|
}
|
|
for (i=bank->nb_banks-2;i>=0;i--)
|
|
{
|
|
bark[i] = bark[i] + decay_low*bark[i+1];
|
|
}
|
|
filterbank_compute_psd(bank, bark, mask);
|
|
}
|
|
|
|
#endif
|