FreeCalypso > hg > gsm-codec-lib
view libtwamr/d2_11pf.c @ 391:be8edf9e6bc1
libtwamr: integrate pitch_fr.c
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Mon, 06 May 2024 18:30:00 +0000 |
parents | c75327562b5e |
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 : d2_11pf.c * Purpose : Algebraic codebook decoder * ******************************************************************************** */ /* ******************************************************************************** * MODULE INCLUDE FILE AND VERSION ID ******************************************************************************** */ #include "namespace.h" #include "d2_11pf.h" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "typedef.h" #include "basic_op.h" #include "no_count.h" #include "cnst.h" /* ******************************************************************************** * LOCAL VARIABLES AND TABLES ******************************************************************************** */ #define NB_PULSE 2 /* number of pulses */ /* ******************************************************************************** * PUBLIC PROGRAM CODE ******************************************************************************** */ /************************************************************************* * * FUNCTION: decode_2i40_11bits (decod_ACELP()) * * PURPOSE: Algebraic codebook decoder * *************************************************************************/ void decode_2i40_11bits( Word16 sign, /* i : signs of 2 pulses. */ Word16 index, /* i : Positions of the 2 pulses. */ Word16 cod[] /* o : algebraic (fixed) codebook excitation */ ) { Word16 i, j; Word16 pos[NB_PULSE]; /* Decode the positions */ j = index & 1; logic16 (); index = shr(index, 1); i = index & 7; logic16 (); i = add(i, shl(i, 2)); /* pos0 =i*5+1+j*2 */ i = add(i, 1); j = shl(j, 1); pos[0] = add(i, j); move16 (); index = shr(index, 3); j = index & 3; logic16 (); index = shr(index, 2); i = index & 7; logic16 (); test(); if (sub(j, 3) == 0) { i = add(i, shl(i, 2)); /* pos1 =i*5+4 */ pos[1] = add(i, 4); move16 (); } else { i = add(i, shl(i, 2)); /* pos1 =i*5+j */ pos[1] = add(i, j); move16 (); } /* decode the signs and build the codeword */ for (i = 0; i < L_SUBFR; i++) { cod[i] = 0; move16 (); } for (j = 0; j < NB_PULSE; j++) { i = sign & 1; logic16 (); sign = shr(sign, 1); test (); if (i != 0) { cod[pos[j]] = 8191; move16 (); /* +1.0 */ } else { cod[pos[j]] = -8192; move16 (); /* -1.0 */ } } return; }