From f02dfce6e6c34b3d8a7b8a0e784b506178e331fa Mon Sep 17 00:00:00 2001 From: "erdgeist@erdgeist.org" Date: Thu, 4 Jul 2019 23:26:09 +0200 Subject: stripdown of version 0.9 --- interp.c | 331 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 331 insertions(+) create mode 100644 interp.c (limited to 'interp.c') diff --git a/interp.c b/interp.c new file mode 100644 index 0000000..2109acb --- /dev/null +++ b/interp.c @@ -0,0 +1,331 @@ +/*---------------------------------------------------------------------------*\ + + 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 . +*/ + +#include +#include +#include +#include + +#include "defines.h" +#include "interp.h" +#include "lsp.h" +#include "quantise.h" + +float sample_log_amp(MODEL *model, float w); + +#if 0 +/*---------------------------------------------------------------------------*\ + + 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 */ + float Wo_min +) +{ + 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 = Wo_min; + } + 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] = powf(10.0, log_amp); + } +} +#endif + +/*---------------------------------------------------------------------------*\ + + 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; +} + +#ifdef NOT_NEEDED + +/*---------------------------------------------------------------------------*\ + + 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( + codec2_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 */ + float Wo_min +) +{ + 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 = Wo_min; + } + 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; iA[1]); +} +#endif + +/*---------------------------------------------------------------------------*\ + + 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 */ + float Wo_min + ) +{ + interp_Wo2(interp, prev, next, 0.5, Wo_min); +} + +/*---------------------------------------------------------------------------*\ + + 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, + float Wo_min +) +{ + /* 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 = Wo_min; + } + 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); + return sqrtf(prev_e * next_e); //looks better is math. identical and faster math +} + + +/*---------------------------------------------------------------------------*\ + + 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 POW10F((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 order) +{ + int i; + + for(i=0; i