FreeCalypso > hg > gsm-codec-lib
view libtwamr/spreproc.c @ 419:2a094af3d384
libtwamr: implement encoder top level
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Tue, 07 May 2024 04:51:04 +0000 |
parents | 7e0aeab69b10 |
children |
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/* ******************************************************************************** * * GSM AMR-NB speech codec R98 Version 7.6.0 December 12, 2001 * R99 Version 3.3.0 * REL-4 Version 4.1.0 * ******************************************************************************** * * File : spreproc.c * Purpose : Subframe preprocessing * ******************************************************************************** */ /* ******************************************************************************** * MODULE INCLUDE FILE AND VERSION ID ******************************************************************************** */ #include "namespace.h" #include "spreproc.h" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "typedef.h" #include "basic_op.h" #include "oper_32b.h" #include "weight_a.h" #include "syn_filt.h" #include "residu.h" #include "memops.h" #include "no_count.h" /* ******************************************************************************** * PUBLIC PROGRAM CODE ******************************************************************************** */ int subframePreProc( enum Mode mode, /* i : coder mode */ const Word16 gamma1[], /* i : spectral exp. factor 1 */ const Word16 gamma1_12k2[],/* i : spectral exp. factor 1 for EFR */ const Word16 gamma2[], /* i : spectral exp. factor 2 */ Word16 *A, /* i : A(z) unquantized for the 4 subframes */ Word16 *Aq, /* i : A(z) quantized for the 4 subframes */ Word16 *speech, /* i : speech segment */ Word16 *mem_err, /* i : pointer to error signal */ Word16 *mem_w0, /* i : memory of weighting filter */ Word16 *zero, /* i : pointer to zero vector */ Word16 ai_zero[], /* o : history of weighted synth. filter */ Word16 exc[], /* o : long term prediction residual */ Word16 h1[], /* o : impulse response */ Word16 xn[], /* o : target vector for pitch search */ Word16 res2[], /* o : long term prediction residual */ Word16 error[] /* o : error of LPC synthesis filter */ ) { Word16 i; Word16 Ap1[MP1]; /* A(z) with spectral expansion */ Word16 Ap2[MP1]; /* A(z) with spectral expansion */ const Word16 *g1; /* Pointer to correct gammma1 vector */ /*---------------------------------------------------------------* * mode specific pointer to gamma1 values * *---------------------------------------------------------------*/ test (); test (); if ( sub(mode, MR122) == 0 || sub(mode, MR102) == 0 ) { g1 = gamma1_12k2; move16 (); } else { g1 = gamma1; move16 (); } /*---------------------------------------------------------------* * Find the weighted LPC coefficients for the weighting filter. * *---------------------------------------------------------------*/ Weight_Ai(A, g1, Ap1); Weight_Ai(A, gamma2, Ap2); /*---------------------------------------------------------------* * Compute impulse response, h1[], of weighted synthesis filter * *---------------------------------------------------------------*/ for (i = 0; i <= M; i++) { ai_zero[i] = Ap1[i]; move16 (); } Syn_filt(Aq, ai_zero, h1, L_SUBFR, zero, 0); Syn_filt(Ap2, h1, h1, L_SUBFR, zero, 0); /*------------------------------------------------------------------------* * * * Find the target vector for pitch search: * * * *------------------------------------------------------------------------*/ /* LPC residual */ Residu(Aq, speech, res2, L_SUBFR); Copy(res2, exc, L_SUBFR); Syn_filt(Aq, exc, error, L_SUBFR, mem_err, 0); Residu(Ap1, error, xn, L_SUBFR); /* target signal xn[]*/ Syn_filt(Ap2, xn, xn, L_SUBFR, mem_w0, 0); return 0; }