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diff --git a/lib/rbcodec/codecs/libspeex/filterbank.c b/lib/rbcodec/codecs/libspeex/filterbank.c
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+/* 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.
+*/
+
+#ifdef HAVE_CONFIG_H
+#include "config-speex.h"
+#endif
+
+#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