FreeCalypso > hg > gsm-codec-lib
view libtwamr/lsp.c @ 478:936a08cc73ce
doc/AMR-library-API: describe the decoder
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Sun, 19 May 2024 21:32:31 +0000 |
parents | 550d3594c878 |
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 : lsp.c * Purpose : From A(z) to lsp. LSP quantization and interpolation * ******************************************************************************** */ /* ******************************************************************************** * MODULE INCLUDE FILE AND VERSION ID ******************************************************************************** */ #include "namespace.h" #include "lsp.h" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "tw_amr.h" #include "typedef.h" #include "basic_op.h" #include "oper_32b.h" #include "q_plsf.h" #include "memops.h" #include "az_lsp.h" #include "int_lpc.h" #include "no_count.h" #include "lsp_tab.h" /* ******************************************************************************** * PUBLIC PROGRAM CODE ******************************************************************************** */ /* ************************************************************************** * * Function : lsp_reset * ************************************************************************** */ void lsp_reset (lspState *st) { /* Init lsp_old[] */ Copy(lsp_init_data, &st->lsp_old[0], M); /* Initialize lsp_old_q[] */ Copy(st->lsp_old, st->lsp_old_q, M); /* Reset quantization state */ Q_plsf_reset(&st->qSt); } /************************************************************************* * * FUNCTION: lsp() * ************************************************************************/ int lsp(lspState *st, /* i/o : State struct */ enum Mode req_mode, /* i : requested coder mode */ enum Mode used_mode, /* i : used coder mode */ Word16 az[], /* i/o : interpolated LP parameters Q12 */ Word16 azQ[], /* o : quantization interpol. LP parameters Q12*/ Word16 lsp_new[], /* o : new lsp vector */ Word16 **anap /* o : analysis parameters */) { Word16 lsp_new_q[M]; /* LSPs at 4th subframe */ Word16 lsp_mid[M], lsp_mid_q[M]; /* LSPs at 2nd subframe */ Word16 pred_init_i; /* init index for MA prediction in DTX mode */ test (); if ( sub (req_mode, MR122) == 0) { Az_lsp (&az[MP1], lsp_mid, st->lsp_old); Az_lsp (&az[MP1 * 3], lsp_new, lsp_mid); /*--------------------------------------------------------------------* * Find interpolated LPC parameters in all subframes (both quantized * * and unquantized). * * The interpolated parameters are in array A_t[] of size (M+1)*4 * * and the quantized interpolated parameters are in array Aq_t[] * *--------------------------------------------------------------------*/ Int_lpc_1and3_2 (st->lsp_old, lsp_mid, lsp_new, az); test (); if ( sub (used_mode, MRDTX) != 0) { /* LSP quantization (lsp_mid[] and lsp_new[] jointly quantized) */ Q_plsf_5 (&st->qSt, lsp_mid, lsp_new, lsp_mid_q, lsp_new_q, *anap); Int_lpc_1and3 (st->lsp_old_q, lsp_mid_q, lsp_new_q, azQ); /* Advance analysis parameters pointer */ (*anap) += add(0,5); move16 (); } } else { Az_lsp(&az[MP1 * 3], lsp_new, st->lsp_old); /* From A(z) to lsp */ /*--------------------------------------------------------------------* * Find interpolated LPC parameters in all subframes (both quantized * * and unquantized). * * The interpolated parameters are in array A_t[] of size (M+1)*4 * * and the quantized interpolated parameters are in array Aq_t[] * *--------------------------------------------------------------------*/ Int_lpc_1to3_2(st->lsp_old, lsp_new, az); test (); if ( sub (used_mode, MRDTX) != 0) { /* LSP quantization */ Q_plsf_3(&st->qSt, req_mode, lsp_new, lsp_new_q, *anap, &pred_init_i); Int_lpc_1to3(st->lsp_old_q, lsp_new_q, azQ); /* Advance analysis parameters pointer */ (*anap) += add (0, 3); move16 (); } } /* update the LSPs for the next frame */ Copy (lsp_new, st->lsp_old, M); Copy (lsp_new_q, st->lsp_old_q, M); return 0; }