ref: 104c218c9b1565a8d4bc403fea1a527c19271935
dir: /libcelt/quant_bands.c/
/* (C) 2007-2008 Jean-Marc Valin, CSIRO
*/
/*
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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "quant_bands.h"
#include "laplace.h"
#include <math.h>
#include "os_support.h"
#include "arch.h"
#include "mathops.h"
#include "stack_alloc.h"
#ifdef FIXED_POINT
const celt_word16_t eMeans[24] = {11520, -2048, -3072, -640, 256, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
#else
const celt_word16_t eMeans[24] = {45.f, -8.f, -12.f, -2.5f, 1.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f};
#endif
/*const int frac[24] = {4, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2};*/
const int frac[24] = {8, 6, 5, 4, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2};
#ifdef FIXED_POINT
static inline celt_ener_t dB2Amp(celt_ener_t dB)
{
celt_ener_t amp;
amp = PSHR32(celt_exp2(MULT16_16_Q14(21771,dB)),2)-QCONST16(.3f, 14);
if (amp < 0)
amp = 0;
return amp;
}
#define DBofTWO 24661
static inline celt_word16_t amp2dB(celt_ener_t amp)
{
/* equivalent to return 6.0207*log2(.3+amp) */
return ROUND(MULT16_16(24661,celt_log2(ADD32(QCONST32(.3f,14),amp))),12);
/* return DB_SCALING*20*log10(.3+ENER_SCALING_1*amp); */
}
#else
static inline celt_ener_t dB2Amp(celt_ener_t dB)
{
celt_ener_t amp;
amp = pow(10, .05*dB)-.3;
if (amp < 0)
amp = 0;
return amp;
}
static inline celt_word16_t amp2dB(celt_ener_t amp)
{
return 20*log10(.3+amp);
}
#endif
static const celt_word16_t base_resolution = QCONST16(6.f,8);
static void quant_energy_mono(const CELTMode *m, celt_ener_t *eBands, celt_word16_t *oldEBands, unsigned budget, ec_enc *enc)
{
int i;
unsigned bits;
celt_word16_t prev = 0;
celt_word16_t coef = m->ePredCoef;
celt_word16_t beta;
VARDECL(celt_word16_t, error);
SAVE_STACK;
/* The .7 is a heuristic */
beta = MULT16_16_Q15(QCONST16(.7f,15),coef);
ALLOC(error, m->nbEBands, celt_word16_t);
bits = ec_enc_tell(enc, 0);
for (i=0;i<m->nbEBands;i++)
{
int qi;
celt_word16_t q; /* dB */
celt_word16_t x; /* dB */
celt_word16_t f; /* Q8 */
celt_word16_t mean = MULT16_16_Q15(Q15ONE-coef,eMeans[i]);
x = amp2dB(eBands[i]);
f = DIV32_16(SHL32(EXTEND32(x-mean-MULT16_16_Q15(coef,oldEBands[i])-prev),8),base_resolution);
#ifdef FIXED_POINT
/* Rounding to nearest integer here is really important! */
qi = (f+128)>>8;
#else
qi = (int)floor(.5+f);
#endif
/*ec_laplace_encode(enc, qi, i==0?11192:6192);*/
/*ec_laplace_encode(enc, qi, 8500-i*200);*/
/* If we don't have enough bits to encode all the energy, just assume something safe. */
if (ec_enc_tell(enc, 0) - bits > budget)
qi = -1;
else
ec_laplace_encode(enc, qi, 6000-i*200);
q = qi*base_resolution;
error[i] = f - SHL16(qi,8);
/*printf("%d ", qi);*/
/*printf("%f %f ", pred+prev+q, x);*/
/*printf("%f ", x-pred);*/
oldEBands[i] = mean+MULT16_16_Q15(coef,oldEBands[i])+prev+q;
prev = mean+prev+MULT16_16_Q15(Q15ONE-beta,q);
}
/*bits = ec_enc_tell(enc, 0) - bits;*/
/*printf ("%d\n", bits);*/
for (i=0;i<m->nbEBands;i++)
{
int q2;
celt_word16_t offset = (error[i]+QCONST16(.5f,8))*frac[i];
/* FIXME: Instead of giving up without warning, we should degrade everything gracefully */
if (ec_enc_tell(enc, 0) - bits +EC_ILOG(frac[i])> budget)
break;
#ifdef FIXED_POINT
/* Has to be without rounding */
q2 = offset>>8;
#else
q2 = (int)floor(offset);
#endif
if (q2 > frac[i]-1)
q2 = frac[i]-1;
ec_enc_uint(enc, q2, frac[i]);
offset = DIV32_16(SHL16(q2,8)+QCONST16(.5,8),frac[i])-QCONST16(.5f,8);
oldEBands[i] += PSHR32(MULT16_16(DB_SCALING*6,offset),8);
/*printf ("%f ", error[i] - offset);*/
}
for (i=0;i<m->nbEBands;i++)
{
eBands[i] = dB2Amp(oldEBands[i]);
}
/*printf ("%d\n", ec_enc_tell(enc, 0)-9);*/
/*printf ("\n");*/
RESTORE_STACK;
}
static void unquant_energy_mono(const CELTMode *m, celt_ener_t *eBands, celt_word16_t *oldEBands, unsigned budget, ec_dec *dec)
{
int i;
unsigned bits;
celt_word16_t prev = 0;
celt_word16_t coef = m->ePredCoef;
/* The .7 is a heuristic */
celt_word16_t beta = MULT16_16_Q15(QCONST16(.7f,15),coef);
bits = ec_dec_tell(dec, 0);
for (i=0;i<m->nbEBands;i++)
{
int qi;
celt_word16_t q;
celt_word16_t mean = MULT16_16_Q15(Q15ONE-coef,eMeans[i]);
/* If we didn't have enough bits to encode all the energy, just assume something safe. */
if (ec_dec_tell(dec, 0) - bits > budget)
qi = -1;
else
qi = ec_laplace_decode(dec, 6000-i*200);
q = qi*base_resolution;
/*printf("%d ", qi);*/
/*printf("%f %f ", pred+prev+q, x);*/
/*printf("%f ", x-pred);*/
oldEBands[i] = mean+MULT16_16_Q15(coef,oldEBands[i])+prev+q;
prev = mean+prev+MULT16_16_Q15(Q15ONE-beta,q);
}
for (i=0;i<m->nbEBands;i++)
{
int q2;
celt_word16_t offset;
if (ec_dec_tell(dec, 0) - bits +EC_ILOG(frac[i])> budget)
break;
q2 = ec_dec_uint(dec, frac[i]);
offset = DIV32_16(SHL16(q2,8)+QCONST16(.5,8),frac[i])-QCONST16(.5f,8);
oldEBands[i] += PSHR32(MULT16_16(DB_SCALING*6,offset),8);
}
for (i=0;i<m->nbEBands;i++)
{
eBands[i] = dB2Amp(oldEBands[i]);
}
/*printf ("\n");*/
}
void quant_energy(const CELTMode *m, celt_ener_t *eBands, celt_word16_t *oldEBands, int budget, ec_enc *enc)
{
int C;
SAVE_STACK;
C = m->nbChannels;
if (C==1)
quant_energy_mono(m, eBands, oldEBands, budget, enc);
else
#if 1
{
int c;
VARDECL(celt_ener_t, E);
ALLOC(E, m->nbEBands, celt_ener_t);
for (c=0;c<C;c++)
{
int i;
for (i=0;i<m->nbEBands;i++)
E[i] = eBands[C*i+c];
quant_energy_mono(m, E, oldEBands+c*m->nbEBands, budget/C, enc);
for (i=0;i<m->nbEBands;i++)
eBands[C*i+c] = E[i];
}
}
#else
if (C==2)
{
int i;
int NB = m->nbEBands;
celt_ener_t mid[NB];
celt_ener_t side[NB];
for (i=0;i<NB;i++)
{
//left = eBands[C*i];
//right = eBands[C*i+1];
mid[i] = ENER_SCALING_1*sqrt(eBands[C*i]*eBands[C*i] + eBands[C*i+1]*eBands[C*i+1]);
side[i] = 20*log10((ENER_SCALING_1*eBands[2*i]+.3)/(ENER_SCALING_1*eBands[2*i+1]+.3));
//printf ("%f %f ", mid[i], side[i]);
}
//printf ("\n");
quant_energy_mono(m, mid, oldEBands, enc);
for (i=0;i<NB;i++)
side[i] = pow(10.f,floor(.5f+side[i])/10.f);
//quant_energy_side(m, side, oldEBands+NB, enc);
for (i=0;i<NB;i++)
{
eBands[C*i] = ENER_SCALING*mid[i]*sqrt(side[i]/(1.f+side[i]));
eBands[C*i+1] = ENER_SCALING*mid[i]*sqrt(1.f/(1.f+side[i]));
//printf ("%f %f ", mid[i], side[i]);
}
} else {
celt_fatal("more than 2 channels not supported");
}
#endif
RESTORE_STACK;
}
void unquant_energy(const CELTMode *m, celt_ener_t *eBands, celt_word16_t *oldEBands, int budget, ec_dec *dec)
{
int C;
SAVE_STACK;
C = m->nbChannels;
if (C==1)
unquant_energy_mono(m, eBands, oldEBands, budget, dec);
else {
int c;
VARDECL(celt_ener_t, E);
ALLOC(E, m->nbEBands, celt_ener_t);
for (c=0;c<C;c++)
{
int i;
unquant_energy_mono(m, E, oldEBands+c*m->nbEBands, budget/C, dec);
for (i=0;i<m->nbEBands;i++)
eBands[C*i+c] = E[i];
}
}
RESTORE_STACK;
}