FreeCalypso > hg > gsm-codec-lib
view libtwamr/d_plsf.h @ 478:936a08cc73ce
doc/AMR-library-API: describe the decoder
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Sun, 19 May 2024 21:32:31 +0000 |
parents | 3f574255c3aa |
children |
line wrap: on
line source
/* ******************************************************************************** * * 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 : d_plsf.h * Purpose : common part (init, exit, reset) of LSF decoder * module (rest in d_plsf_3.c and d_plsf_5.c) * ******************************************************************************** */ #ifndef d_plsf_h #define d_plsf_h "$Id $" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "tw_amr.h" #include "typedef.h" #include "cnst.h" /* ******************************************************************************** * LOCAL VARIABLES AND TABLES ******************************************************************************** */ /* *--------------------------------------------------* * Constants (defined in cnst.h) * *--------------------------------------------------* * M : LPC Order * *--------------------------------------------------* */ /* ******************************************************************************** * DEFINITION OF DATA TYPES ******************************************************************************** */ typedef struct { Word16 past_r_q[M]; /* Past quantized prediction error, Q15 */ Word16 past_lsf_q[M]; /* Past dequantized lsfs, Q15 */ } D_plsfState; /* ******************************************************************************** * DECLARATION OF PROTOTYPES ******************************************************************************** */ /* ************************************************************************** * * Function : D_plsf_reset * Purpose : Resets state memory * Returns : 0 on success * ************************************************************************** */ void D_plsf_reset (D_plsfState *st); /* ************************************************************************** * * Function : D_plsf_5 * Purpose : Decodes the 2 sets of LSP parameters in a frame * using the received quantization indices. * Description : The two sets of LSFs are quantized using split by * 5 matrix quantization (split-MQ) with 1st order MA * prediction. * See "q_plsf_5.c" for more details about the * quantization procedure * Returns : 0 * ************************************************************************** */ int D_plsf_5 ( D_plsfState *st, /* i/o: State variables */ Word16 bfi, /* i : bad frame indicator (set to 1 if a bad frame is received) */ Word16 *indice, /* i : quantization indices of 5 submatrices, Q0 */ Word16 *lsp1_q, /* o : quantized 1st LSP vector (M) Q15 */ Word16 *lsp2_q /* o : quantized 2nd LSP vector (M) Q15 */ ); /************************************************************************* * * FUNCTION: D_plsf_3() * * PURPOSE: Decodes the LSP parameters using the received quantization * indices.1st order MA prediction and split by 3 matrix * quantization (split-MQ) * *************************************************************************/ void D_plsf_3( D_plsfState *st, /* i/o: State struct */ enum Mode mode, /* i : coder mode */ Word16 bfi, /* i : bad frame indicator (set to 1 if a */ /* bad frame is received) */ Word16 * indice, /* i : quantization indices of 3 submatrices, Q0 */ Word16 * lsp1_q /* o : quantized 1st LSP vector, Q15 */ ); /************************************************************************* * * FUNCTION: Init_D_plsf_3() * * PURPOSE: Set the past_r_q[M] vector to one of the eight * past_rq_init vectors. * *************************************************************************/ void Init_D_plsf_3(D_plsfState *st, /* i/o: State struct */ Word16 index /* i : past_rq_init[] index [0, 7] */ ); #endif