eden-emu/opus
17
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

fixed-point: compute_band_energies() converted. Had to add some tiny bias to

Browse source 
make sure never to end up with a pitch vector with >1 norm.
This commit is contained in:
Jean-Marc Valin 2008-03-07 16:42:31 +11:00
parent 0668b8ea5e
commit 000973f7e2
1 changed files with 40 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

50
libcelt/bands.c
View file

@ -71,6 +71,10 @@ void exp_rotation(celt_norm_t *X, int len, int dir, int stride, int iter)
} }
} }
const celt_word16_t sqrtC_1[2] = {QCONST16(1.f, 14), QCONST16(1.414214f, 14)};
#ifdef FIXED_POINT
/* Compute the amplitude (sqrt energy) in each of the bands */ /* Compute the amplitude (sqrt energy) in each of the bands */
void compute_band_energies(const CELTMode *m, const celt_sig_t *X, celt_ener_t *bank) void compute_band_energies(const CELTMode *m, const celt_sig_t *X, celt_ener_t *bank)
{ {
@ -83,19 +87,27 @@ void compute_band_energies(const CELTMode *m, const celt_sig_t *X, celt_ener_t *
for (i=0;i<m->nbEBands;i++) for (i=0;i<m->nbEBands;i++)
{ {
int j; int j;
float sum = 1e-10; celt_word32_t maxval=0;
celt_word32_t sum = 0;
for (j=B*eBands[i];j<B*eBands[i+1];j++) for (j=B*eBands[i];j<B*eBands[i+1];j++)
sum += SIG_SCALING_1*SIG_SCALING_1*X[j*C+c]*X[j*C+c]; maxval = MAX32(maxval, ABS32(X[j*C+c]));
bank[i*C+c] = ENER_SCALING*sqrt(sum); if (maxval > 0)
{
int shift = celt_ilog2(maxval)-10;
for (j=B*eBands[i];j<B*eBands[i+1];j++)
sum += VSHR32(X[j*C+c],shift)*VSHR32(X[j*C+c],shift);
/* We're adding one here to make damn sure we never end up with a pitch vector that's
larger than unity norm */
bank[i*C+c] = 1+VSHR32(EXTEND32(celt_sqrt(sum)),-shift);
} else {
bank[i*C+c] = 0;
}
/*printf ("%f ", bank[i*C+c]);*/ /*printf ("%f ", bank[i*C+c]);*/
} }
} }
/*printf ("\n");*/ /*printf ("\n");*/
} }
const celt_word16_t sqrtC_1[2] = {QCONST16(1.f, 14), QCONST16(1.414214f, 14)};
#ifdef FIXED_POINT
/* Normalise each band such that the energy is one. */ /* Normalise each band such that the energy is one. */
void normalise_bands(const CELTMode *m, const celt_sig_t *freq, celt_norm_t *X, const celt_ener_t *bank) void normalise_bands(const CELTMode *m, const celt_sig_t *freq, celt_norm_t *X, const celt_ener_t *bank)
{ {
@ -139,6 +151,28 @@ void renormalise_bands(const CELTMode *m, celt_norm_t *X)
RESTORE_STACK; RESTORE_STACK;
} }
#else #else
/* Compute the amplitude (sqrt energy) in each of the bands */
void compute_band_energies(const CELTMode *m, const celt_sig_t *X, celt_ener_t *bank)
{
int i, c, B, C;
const int *eBands = m->eBands;
B = m->nbMdctBlocks;
C = m->nbChannels;
for (c=0;c<C;c++)
{
for (i=0;i<m->nbEBands;i++)
{
int j;
float sum = 1e-10;
for (j=B*eBands[i];j<B*eBands[i+1];j++)
sum += SIG_SCALING_1*SIG_SCALING_1*X[j*C+c]*X[j*C+c];
bank[i*C+c] = ENER_SCALING*sqrt(sum);
/*printf ("%f ", bank[i*C+c]);*/
}
}
/*printf ("\n");*/
}
/* Normalise each band such that the energy is one. */ /* Normalise each band such that the energy is one. */
void normalise_bands(const CELTMode *m, const celt_sig_t *freq, celt_norm_t *X, const celt_ener_t *bank) void normalise_bands(const CELTMode *m, const celt_sig_t *freq, celt_norm_t *X, const celt_ener_t *bank)
{ {
@ -284,8 +318,6 @@ void quant_bands(const CELTMode *m, celt_norm_t *X, celt_norm_t *P, celt_mask_t
int q; int q;
celt_word16_t n; celt_word16_t n;
q = pulses[i]; q = pulses[i];
/*Scale factor of .0625f is just there to prevent overflows in fixed-point
(has no effect on float)*/
n = SHL16(celt_sqrt(B*(eBands[i+1]-eBands[i])),11); n = SHL16(celt_sqrt(B*(eBands[i+1]-eBands[i])),11);
/* If pitch isn't available, use intra-frame prediction */ /* If pitch isn't available, use intra-frame prediction */
@ -345,8 +377,6 @@ void unquant_bands(const CELTMode *m, celt_norm_t *X, celt_norm_t *P, int total_
int q; int q;
celt_word16_t n; celt_word16_t n;
q = pulses[i]; q = pulses[i];
/*Scale factor of .0625f is just there to prevent overflows in fixed-point
(has no effect on float)*/
n = SHL16(celt_sqrt(B*(eBands[i+1]-eBands[i])),11); n = SHL16(celt_sqrt(B*(eBands[i+1]-eBands[i])),11);
/* If pitch isn't available, use intra-frame prediction */ /* If pitch isn't available, use intra-frame prediction */