You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
269 lines
8.2 KiB
269 lines
8.2 KiB
4 years ago
|
/* Copyright (C) 2002 Jean-Marc Valin
|
||
|
File: vbr.c
|
||
|
|
||
|
VBR-related routines
|
||
|
|
||
|
Redistribution and use in source and binary forms, with or without
|
||
|
modification, are permitted provided that the following conditions
|
||
|
are met:
|
||
|
|
||
|
- Redistributions of source code must retain the above copyright
|
||
|
notice, this list of conditions and the following disclaimer.
|
||
|
|
||
|
- 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.
|
||
|
|
||
|
- Neither the name of the Xiph.org Foundation nor the names of its
|
||
|
contributors may be used to endorse or promote products derived from
|
||
|
this software without specific prior written permission.
|
||
|
|
||
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||
|
``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 FOUNDATION OR
|
||
|
CONTRIBUTORS 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 "vbr.h"
|
||
|
#include <math.h>
|
||
|
|
||
|
|
||
|
#define sqr(x) ((x)*(x))
|
||
|
|
||
|
#define MIN_ENERGY 6000
|
||
|
#define NOISE_POW .3
|
||
|
|
||
|
|
||
|
float vbr_nb_thresh[9][11]={
|
||
|
{-1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0}, /* CNG */
|
||
|
{ 3.5, 2.5, 2.0, 1.2, 0.5, 0.0, -0.5, -0.7, -0.8, -0.9, -1.0}, /* 2 kbps */
|
||
|
{10.0, 6.5, 5.2, 4.5, 3.9, 3.5, 3.0, 2.5, 2.3, 1.8, 1.0}, /* 6 kbps */
|
||
|
{11.0, 8.8, 7.5, 6.5, 5.0, 3.9, 3.9, 3.9, 3.5, 3.0, 1.0}, /* 8 kbps */
|
||
|
{11.0, 11.0, 9.9, 9.0, 8.0, 7.0, 6.5, 6.0, 5.0, 4.0, 2.0}, /* 11 kbps */
|
||
|
{11.0, 11.0, 11.0, 11.0, 9.5, 9.0, 8.0, 7.0, 6.5, 5.0, 3.0}, /* 15 kbps */
|
||
|
{11.0, 11.0, 11.0, 11.0, 11.0, 11.0, 9.5, 8.5, 8.0, 6.5, 4.0}, /* 18 kbps */
|
||
|
{11.0, 11.0, 11.0, 11.0, 11.0, 11.0, 11.0, 11.0, 9.8, 7.5, 5.5}, /* 24 kbps */
|
||
|
{ 8.0, 5.0, 3.7, 3.0, 2.5, 2.0, 1.8, 1.5, 1.0, 0.0, 0.0} /* 4 kbps */
|
||
|
};
|
||
|
|
||
|
|
||
|
float vbr_hb_thresh[5][11]={
|
||
|
{-1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0}, /* silence */
|
||
|
{-1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0}, /* 2 kbps */
|
||
|
{11.0, 11.0, 9.5, 8.5, 7.5, 6.0, 5.0, 3.9, 3.0, 2.0, 1.0}, /* 6 kbps */
|
||
|
{11.0, 11.0, 11.0, 11.0, 11.0, 9.5, 8.7, 7.8, 7.0, 6.5, 4.0}, /* 10 kbps */
|
||
|
{11.0, 11.0, 11.0, 11.0, 11.0, 11.0, 11.0, 11.0, 9.8, 7.5, 5.5} /* 18 kbps */
|
||
|
};
|
||
|
|
||
|
float vbr_uhb_thresh[2][11]={
|
||
|
{-1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0}, /* silence */
|
||
|
{ 3.9, 2.5, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, -1.0} /* 2 kbps */
|
||
|
};
|
||
|
|
||
|
void vbr_init(VBRState *vbr)
|
||
|
{
|
||
|
int i;
|
||
|
|
||
|
vbr->average_energy=0;
|
||
|
vbr->last_energy=1;
|
||
|
vbr->accum_sum=0;
|
||
|
vbr->energy_alpha=.1;
|
||
|
vbr->soft_pitch=0;
|
||
|
vbr->last_pitch_coef=0;
|
||
|
vbr->last_quality=0;
|
||
|
|
||
|
vbr->noise_accum = .05*pow(MIN_ENERGY, NOISE_POW);
|
||
|
vbr->noise_accum_count=.05;
|
||
|
vbr->noise_level=vbr->noise_accum/vbr->noise_accum_count;
|
||
|
vbr->consec_noise=0;
|
||
|
|
||
|
|
||
|
for (i=0;i<VBR_MEMORY_SIZE;i++)
|
||
|
vbr->last_log_energy[i] = log(MIN_ENERGY);
|
||
|
}
|
||
|
|
||
|
|
||
|
/*
|
||
|
This function should analyse the signal and decide how critical the
|
||
|
coding error will be perceptually. The following factors should be
|
||
|
taken into account:
|
||
|
|
||
|
-Attacks (positive energy derivative) should be coded with more bits
|
||
|
|
||
|
-Stationary voiced segments should receive more bits
|
||
|
|
||
|
-Segments with (very) low absolute energy should receive less bits (maybe
|
||
|
only shaped noise?)
|
||
|
|
||
|
-DTX for near-zero energy?
|
||
|
|
||
|
-Stationary fricative segments should have less bits
|
||
|
|
||
|
-Temporal masking: when energy slope is decreasing, decrease the bit-rate
|
||
|
|
||
|
-Decrease bit-rate for males (low pitch)?
|
||
|
|
||
|
-(wideband only) less bits in the high-band when signal is very
|
||
|
non-stationary (harder to notice high-frequency noise)???
|
||
|
|
||
|
*/
|
||
|
|
||
|
float vbr_analysis(VBRState *vbr, float *sig, int len, int pitch, float pitch_coef)
|
||
|
{
|
||
|
int i;
|
||
|
float ener=0, ener1=0, ener2=0;
|
||
|
float qual=7;
|
||
|
int va;
|
||
|
float log_energy;
|
||
|
float non_st=0;
|
||
|
float voicing;
|
||
|
float pow_ener;
|
||
|
|
||
|
for (i=0;i<len>>1;i++)
|
||
|
ener1 += sig[i]*sig[i];
|
||
|
|
||
|
for (i=len>>1;i<len;i++)
|
||
|
ener2 += sig[i]*sig[i];
|
||
|
ener=ener1+ener2;
|
||
|
|
||
|
log_energy = log(ener+MIN_ENERGY);
|
||
|
for (i=0;i<VBR_MEMORY_SIZE;i++)
|
||
|
non_st += sqr(log_energy-vbr->last_log_energy[i]);
|
||
|
non_st = non_st/(30*VBR_MEMORY_SIZE);
|
||
|
if (non_st>1)
|
||
|
non_st=1;
|
||
|
|
||
|
voicing = 3*(pitch_coef-.4)*fabs(pitch_coef-.4);
|
||
|
vbr->average_energy = (1-vbr->energy_alpha)*vbr->average_energy + vbr->energy_alpha*ener;
|
||
|
vbr->noise_level=vbr->noise_accum/vbr->noise_accum_count;
|
||
|
pow_ener = pow(ener,NOISE_POW);
|
||
|
if (vbr->noise_accum_count<.06 && ener>MIN_ENERGY)
|
||
|
vbr->noise_accum = .05*pow_ener;
|
||
|
|
||
|
if ((voicing<.3 && non_st < .2 && pow_ener < 1.2*vbr->noise_level)
|
||
|
|| (voicing<.3 && non_st < .05 && pow_ener < 1.5*vbr->noise_level)
|
||
|
|| (voicing<.4 && non_st < .05 && pow_ener < 1.2*vbr->noise_level)
|
||
|
|| (voicing<0 && non_st < .05))
|
||
|
{
|
||
|
float tmp;
|
||
|
va = 0;
|
||
|
vbr->consec_noise++;
|
||
|
if (pow_ener > 3*vbr->noise_level)
|
||
|
tmp = 3*vbr->noise_level;
|
||
|
else
|
||
|
tmp = pow_ener;
|
||
|
if (vbr->consec_noise>=4)
|
||
|
{
|
||
|
vbr->noise_accum = .95*vbr->noise_accum + .05*tmp;
|
||
|
vbr->noise_accum_count = .95*vbr->noise_accum_count + .05;
|
||
|
}
|
||
|
} else {
|
||
|
va = 1;
|
||
|
vbr->consec_noise=0;
|
||
|
}
|
||
|
|
||
|
if (pow_ener < vbr->noise_level && ener>MIN_ENERGY)
|
||
|
{
|
||
|
vbr->noise_accum = .95*vbr->noise_accum + .05*pow_ener;
|
||
|
vbr->noise_accum_count = .95*vbr->noise_accum_count + .05;
|
||
|
}
|
||
|
|
||
|
/* Checking for very low absolute energy */
|
||
|
if (ener < 30000)
|
||
|
{
|
||
|
qual -= .7;
|
||
|
if (ener < 10000)
|
||
|
qual-=.7;
|
||
|
if (ener < 3000)
|
||
|
qual-=.7;
|
||
|
} else {
|
||
|
float short_diff, long_diff;
|
||
|
short_diff = log((ener+1)/(1+vbr->last_energy));
|
||
|
long_diff = log((ener+1)/(1+vbr->average_energy));
|
||
|
/*fprintf (stderr, "%f %f\n", short_diff, long_diff);*/
|
||
|
|
||
|
if (long_diff<-5)
|
||
|
long_diff=-5;
|
||
|
if (long_diff>2)
|
||
|
long_diff=2;
|
||
|
|
||
|
if (long_diff>0)
|
||
|
qual += .6*long_diff;
|
||
|
if (long_diff<0)
|
||
|
qual += .5*long_diff;
|
||
|
if (short_diff>0)
|
||
|
{
|
||
|
if (short_diff>5)
|
||
|
short_diff=5;
|
||
|
qual += .5*short_diff;
|
||
|
}
|
||
|
/* Checking for energy increases */
|
||
|
if (ener2 > 1.6*ener1)
|
||
|
qual += .5;
|
||
|
}
|
||
|
vbr->last_energy = ener;
|
||
|
vbr->soft_pitch = .6*vbr->soft_pitch + .4*pitch_coef;
|
||
|
qual += 2.2*((pitch_coef-.4) + (vbr->soft_pitch-.4));
|
||
|
|
||
|
if (qual < vbr->last_quality)
|
||
|
qual = .5*qual + .5*vbr->last_quality;
|
||
|
if (qual<4)
|
||
|
qual=4;
|
||
|
if (qual>10)
|
||
|
qual=10;
|
||
|
|
||
|
/*
|
||
|
if (vbr->consec_noise>=2)
|
||
|
qual-=1.3;
|
||
|
if (vbr->consec_noise>=5)
|
||
|
qual-=1.3;
|
||
|
if (vbr->consec_noise>=12)
|
||
|
qual-=1.3;
|
||
|
*/
|
||
|
if (vbr->consec_noise>=3)
|
||
|
qual=4;
|
||
|
|
||
|
if (vbr->consec_noise)
|
||
|
qual -= 1.0 * (log(3.0 + vbr->consec_noise)-log(3));
|
||
|
if (qual<0)
|
||
|
qual=0;
|
||
|
|
||
|
if (ener<60000)
|
||
|
{
|
||
|
if (vbr->consec_noise>2)
|
||
|
qual-=0.5*(log(3.0 + vbr->consec_noise)-log(3));
|
||
|
if (ener<10000&&vbr->consec_noise>2)
|
||
|
qual-=0.5*(log(3.0 + vbr->consec_noise)-log(3));
|
||
|
if (qual<0)
|
||
|
qual=0;
|
||
|
qual += .3*log(ener/60000.0);
|
||
|
}
|
||
|
if (qual<-1)
|
||
|
qual=-1;
|
||
|
|
||
|
/*printf ("%f %f %f %f %d\n", qual, voicing, non_st, pow_ener/(.01+vbr->noise_level), va);*/
|
||
|
|
||
|
vbr->last_pitch_coef = pitch_coef;
|
||
|
vbr->last_quality = qual;
|
||
|
|
||
|
for (i=VBR_MEMORY_SIZE-1;i>0;i--)
|
||
|
vbr->last_log_energy[i] = vbr->last_log_energy[i-1];
|
||
|
vbr->last_log_energy[0] = log_energy;
|
||
|
|
||
|
/*printf ("VBR: %f %f %f %d %f\n", (float)(log_energy-log(vbr->average_energy+MIN_ENERGY)), non_st, voicing, va, vbr->noise_level);*/
|
||
|
|
||
|
return qual;
|
||
|
}
|
||
|
|
||
|
void vbr_destroy(VBRState *vbr)
|
||
|
{
|
||
|
}
|