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i've tested, now you can too

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This commit is contained in:
Brian West
2012-12-20 20:08:42 -06:00
parent d3fcfa8245
commit d67b96af8a
94 changed files with 25305 additions and 2005 deletions
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libs/libcodec2/src/interp.c
+168 -5
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@@ -22,16 +22,18 @@
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <assert.h>
#include <math.h>
#include <string.h>
#include <stdio.h>
#include "defines.h"
#include "interp.h"
#include "lsp.h"
#include "quantise.h"
float sample_log_amp(MODEL *model, float w);
@@ -48,6 +50,12 @@ float sample_log_amp(MODEL *model, float w);
This version can interpolate the amplitudes between two frames of
different Wo and L.
This version works by log linear interpolation, but listening tests
showed it creates problems in background noise, e.g. hts2a and mmt1.
When this function is used (--dec mode) bg noise appears to be
amplitude modulated, and gets louder. The interp_lsp() function
below seems to do a better job.
\*---------------------------------------------------------------------------*/
@@ -108,15 +116,170 @@ float sample_log_amp(MODEL *model, float w)
assert(f <= 1.0);
if (m < 1) {
log_amp = f*log10(model->A[1]);
log_amp = f*log10(model->A[1] + 1E-6);
}
else if ((m+1) > model->L) {
log_amp = (1.0-f)*log10(model->A[model->L]);
log_amp = (1.0-f)*log10(model->A[model->L] + 1E-6);
}
else {
log_amp = (1.0-f)*log10(model->A[m]) + f*log10(model->A[m+1]);
log_amp = (1.0-f)*log10(model->A[m] + 1E-6) +
f*log10(model->A[m+1] + 1E-6);
}
return log_amp;
}
/*---------------------------------------------------------------------------*\
FUNCTION....: interp_lsp()
AUTHOR......: David Rowe
DATE CREATED: 10 Nov 2010
Given two frames decribed by model parameters 20ms apart, determines
the model parameters of the 10ms frame between them. Assumes
voicing is available for middle (interpolated) frame. Outputs are
amplitudes and Wo for the interpolated frame.
This version uses interpolation of LSPs, seems to do a better job
with bg noise.
\*---------------------------------------------------------------------------*/
void interpolate_lsp(
kiss_fft_cfg fft_fwd_cfg,
MODEL *interp, /* interpolated model params */
MODEL *prev, /* previous frames model params */
MODEL *next, /* next frames model params */
float *prev_lsps, /* previous frames LSPs */
float prev_e, /* previous frames LPC energy */
float *next_lsps, /* next frames LSPs */
float next_e, /* next frames LPC energy */
float *ak_interp, /* interpolated aks for this frame */
float *lsps_interp/* interpolated lsps for this frame */
)
{
int i;
float e;
float snr;
/* trap corner case where V est is probably wrong */
if (interp->voiced && !prev->voiced && !next->voiced) {
interp->voiced = 0;
}
/* Wo depends on voicing of this and adjacent frames */
if (interp->voiced) {
if (prev->voiced && next->voiced)
interp->Wo = (prev->Wo + next->Wo)/2.0;
if (!prev->voiced && next->voiced)
interp->Wo = next->Wo;
if (prev->voiced && !next->voiced)
interp->Wo = prev->Wo;
}
else {
interp->Wo = TWO_PI/P_MAX;
}
interp->L = PI/interp->Wo;
//printf(" interp: prev_v: %d next_v: %d prev_Wo: %f next_Wo: %f\n",
// prev->voiced, next->voiced, prev->Wo, next->Wo);
//printf(" interp: Wo: %1.5f L: %d\n", interp->Wo, interp->L);
/* interpolate LSPs */
for(i=0; i<LPC_ORD; i++) {
lsps_interp[i] = (prev_lsps[i] + next_lsps[i])/2.0;
}
/* Interpolate LPC energy in log domain */
e = pow(10.0, (log10(prev_e) + log10(next_e))/2.0);
//printf(" interp: e: %f\n", e);
/* convert back to amplitudes */
lsp_to_lpc(lsps_interp, ak_interp, LPC_ORD);
aks_to_M2(fft_fwd_cfg, ak_interp, LPC_ORD, interp, e, &snr, 0, 0, 1, 1, LPCPF_BETA, LPCPF_GAMMA);
//printf(" interp: ak[1]: %f A[1] %f\n", ak_interp[1], interp->A[1]);
}
/*---------------------------------------------------------------------------*\
FUNCTION....: interp_Wo()
AUTHOR......: David Rowe
DATE CREATED: 22 May 2012
Interpolates centre 10ms sample of Wo and L samples given two
samples 20ms apart. Assumes voicing is available for centre
(interpolated) frame.
\*---------------------------------------------------------------------------*/
void interp_Wo(
MODEL *interp, /* interpolated model params */
MODEL *prev, /* previous frames model params */
MODEL *next /* next frames model params */
)
{
/* trap corner case where voicing est is probably wrong */
if (interp->voiced && !prev->voiced && !next->voiced) {
interp->voiced = 0;
}
/* Wo depends on voicing of this and adjacent frames */
if (interp->voiced) {
if (prev->voiced && next->voiced)
interp->Wo = (prev->Wo + next->Wo)/2.0;
if (!prev->voiced && next->voiced)
interp->Wo = next->Wo;
if (prev->voiced && !next->voiced)
interp->Wo = prev->Wo;
}
else {
interp->Wo = TWO_PI/P_MAX;
}
interp->L = PI/interp->Wo;
}
/*---------------------------------------------------------------------------*\
FUNCTION....: interp_energy()
AUTHOR......: David Rowe
DATE CREATED: 22 May 2012
Interpolates centre 10ms sample of energy given two samples 20ms
apart.
\*---------------------------------------------------------------------------*/
float interp_energy(float prev_e, float next_e)
{
return pow(10.0, (log10(prev_e) + log10(next_e))/2.0);
}
/*---------------------------------------------------------------------------*\
FUNCTION....: interpolate_lsp_ver2()
AUTHOR......: David Rowe
DATE CREATED: 22 May 2012
Weighted interpolation of LSPs.
\*---------------------------------------------------------------------------*/
void interpolate_lsp_ver2(float interp[], float prev[], float next[], float weight)
{
int i;
for(i=0; i<LPC_ORD; i++)
interp[i] = (1.0 - weight)*prev[i] + weight*next[i];
}