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Diffstat (limited to 'gr-vocoder/lib/codec2/interp.c')
| -rw-r--r-- | gr-vocoder/lib/codec2/interp.c | 323 |
1 files changed, 0 insertions, 323 deletions
diff --git a/gr-vocoder/lib/codec2/interp.c b/gr-vocoder/lib/codec2/interp.c deleted file mode 100644 index be89fc3154..0000000000 --- a/gr-vocoder/lib/codec2/interp.c +++ /dev/null @@ -1,323 +0,0 @@ -/*---------------------------------------------------------------------------*\ - - FILE........: interp.c - AUTHOR......: David Rowe - DATE CREATED: 9/10/09 - - Interpolation of 20ms frames to 10ms frames. - -\*---------------------------------------------------------------------------*/ - -/* - Copyright (C) 2009 David Rowe - - All rights reserved. - - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU Lesser General Public License version 2.1, as - published by the Free Software Foundation. This program is - distributed in the hope that it will be useful, but WITHOUT ANY - WARRANTY; without even the implied warranty of MERCHANTABILITY or - FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public - License for more details. - - You should have received a copy of the GNU Lesser General Public License - 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); - -/*---------------------------------------------------------------------------*\ - - FUNCTION....: interp() - AUTHOR......: David Rowe - DATE CREATED: 22/8/10 - - 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 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. - -\*---------------------------------------------------------------------------*/ - -void interpolate( - MODEL *interp, /* interpolated model params */ - MODEL *prev, /* previous frames model params */ - MODEL *next /* next frames model params */ -) -{ - int l; - float w,log_amp; - - /* 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; - - /* Interpolate amplitudes using linear interpolation in log domain */ - - for(l=1; l<=interp->L; l++) { - w = l*interp->Wo; - log_amp = (sample_log_amp(prev, w) + sample_log_amp(next, w))/2.0; - interp->A[l] = pow(10.0, log_amp); - } -} - -/*---------------------------------------------------------------------------*\ - - FUNCTION....: sample_log_amp() - AUTHOR......: David Rowe - DATE CREATED: 22/8/10 - - Samples the amplitude envelope at an arbitrary frequency w. Uses - linear interpolation in the log domain to sample between harmonic - amplitudes. - -\*---------------------------------------------------------------------------*/ - -float sample_log_amp(MODEL *model, float w) -{ - int m; - float f, log_amp; - - assert(w > 0.0); assert (w <= PI); - - m = floorf(w/model->Wo + 0.5); - f = (w - m*model->Wo)/w; - assert(f <= 1.0); - - if (m < 1) { - log_amp = f*log10f(model->A[1] + 1E-6); - } - else if ((m+1) > model->L) { - log_amp = (1.0-f)*log10f(model->A[model->L] + 1E-6); - } - else { - log_amp = (1.0-f)*log10f(model->A[m] + 1E-6) + - f*log10f(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 = powf(10.0, (log10f(prev_e) + log10f(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 */ - ) -{ - interp_Wo2(interp, prev, next, 0.5); -} - -/*---------------------------------------------------------------------------*\ - - FUNCTION....: interp_Wo2() - AUTHOR......: David Rowe - DATE CREATED: 22 May 2012 - - Weighted interpolation of two Wo samples. - -\*---------------------------------------------------------------------------*/ - -void interp_Wo2( - MODEL *interp, /* interpolated model params */ - MODEL *prev, /* previous frames model params */ - MODEL *next, /* next frames model params */ - float weight -) -{ - /* 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 = (1.0 - weight)*prev->Wo + weight*next->Wo; - 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 powf(10.0, (log10f(prev_e) + log10f(next_e))/2.0); - -} - - -/*---------------------------------------------------------------------------*\ - - FUNCTION....: interp_energy2() - AUTHOR......: David Rowe - DATE CREATED: 22 May 2012 - - Interpolates centre 10ms sample of energy given two samples 20ms - apart. - -\*---------------------------------------------------------------------------*/ - -float interp_energy2(float prev_e, float next_e, float weight) -{ - return powf(10.0, (1.0 - weight)*log10f(prev_e) + weight*log10f(next_e)); - -} - - -/*---------------------------------------------------------------------------*\ - - 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]; -} - |