ref: c9cc6d3e346e1bbf6b3f656f314c6099586487b1
dir: /libcelt/quant_bands.c/
/* (C) 2007 Jean-Marc Valin, CSIRO
*/
/*
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are met:
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- Redistributions in binary form must reproduce the above copyright
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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 "quant_bands.h"
#include "laplace.h"
#include <math.h>
#include "os_support.h"
const float 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};
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};
static void quant_energy_mono(const CELTMode *m, float *eBands, float *oldEBands, int budget, ec_enc *enc)
{
int i;
int bits;
float prev = 0;
float coef = m->ePredCoef;
float error[m->nbEBands];
/* The .7 is a heuristic */
float beta = .7*coef;
bits = ec_enc_tell(enc, 0);
for (i=0;i<m->nbEBands;i++)
{
int qi;
float q;
float res;
float x;
float f;
float mean = (1-coef)*eMeans[i];
x = 20*log10(.3+eBands[i]);
res = 6.;
//res = 1;
f = (x-mean-coef*oldEBands[i]-prev)/res;
qi = (int)floor(.5+f);
//if (i> 4 && qi<-2)
// qi = -2;
//ec_laplace_encode(enc, qi, i==0?11192:6192);
//ec_laplace_encode(enc, qi, 8500-i*200);
ec_laplace_encode(enc, qi, 6000-i*200);
q = qi*res;
error[i] = f - qi;
//printf("%d ", qi);
//printf("%f %f ", pred+prev+q, x);
//printf("%f ", x-pred);
oldEBands[i] = mean+coef*oldEBands[i]+prev+q;
prev = mean+prev+(1-beta)*q;
}
//bits = ec_enc_tell(enc, 0) - bits;
//printf ("%d\n", bits);
for (i=0;i<m->nbEBands;i++)
{
int q2;
float offset = (error[i]+.5)*frac[i];
if (ec_enc_tell(enc, 0) - bits +ec_ilog(frac[i])> budget)
break;
q2 = (int)floor(offset);
if (q2 > frac[i]-1)
q2 = frac[i]-1;
ec_enc_uint(enc, q2, frac[i]);
offset = ((q2+.5)/frac[i])-.5;
oldEBands[i] += 6.*offset;
//printf ("%f ", error[i] - offset);
}
for (i=0;i<m->nbEBands;i++)
{
eBands[i] = pow(10, .05*oldEBands[i])-.3;
if (eBands[i] < 0)
eBands[i] = 0;
}
//printf ("%d\n", ec_enc_tell(enc, 0)-9);
//printf ("\n");
}
static void unquant_energy_mono(const CELTMode *m, float *eBands, float *oldEBands, int budget, ec_dec *dec)
{
int i;
int bits;
float prev = 0;
float coef = m->ePredCoef;
/* The .7 is a heuristic */
float beta = .7*coef;
bits = ec_dec_tell(dec, 0);
for (i=0;i<m->nbEBands;i++)
{
int qi;
float q;
float res;
float mean = (1-coef)*eMeans[i];
res = 6.;
qi = ec_laplace_decode(dec, 6000-i*200);
q = qi*res;
oldEBands[i] = mean+coef*oldEBands[i]+prev+q;
prev = mean+prev+(1-beta)*q;
}
for (i=0;i<m->nbEBands;i++)
{
int q2;
float offset;
if (ec_dec_tell(dec, 0) - bits +ec_ilog(frac[i])> budget)
break;
q2 = ec_dec_uint(dec, frac[i]);
offset = ((q2+.5)/frac[i])-.5;
oldEBands[i] += 6.*offset;
}
for (i=0;i<m->nbEBands;i++)
{
//printf ("%f ", error[i] - offset);
eBands[i] = pow(10, .05*oldEBands[i])-.3;
if (eBands[i] < 0)
eBands[i] = 0;
}
//printf ("\n");
}
void quant_energy(const CELTMode *m, float *eBands, float *oldEBands, int budget, ec_enc *enc)
{
int C;
C = m->nbChannels;
if (C==1)
quant_energy_mono(m, eBands, oldEBands, budget, enc);
else
#if 1
{
int c;
for (c=0;c<C;c++)
{
int i;
float E[m->nbEBands];
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;
float mid[NB];
float side[NB];
float left;
float right;
for (i=0;i<NB;i++)
{
//left = eBands[C*i];
//right = eBands[C*i+1];
mid[i] = sqrt(eBands[C*i]*eBands[C*i] + eBands[C*i+1]*eBands[C*i+1]);
side[i] = 20*log10((eBands[2*i]+.3)/(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] = mid[i]*sqrt(side[i]/(1.f+side[i]));
eBands[C*i+1] = 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
}
void unquant_energy(const CELTMode *m, float *eBands, float *oldEBands, int budget, ec_dec *dec)
{
int C;
C = m->nbChannels;
if (C==1)
unquant_energy_mono(m, eBands, oldEBands, budget, dec);
else {
int c;
for (c=0;c<C;c++)
{
int i;
float E[m->nbEBands];
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];
}
}
}