FreeCalypso > hg > gsm-codec-lib
view libtwamr/d4_17pf.c @ 422:1ceda5586d01
implement twamr-tseq-enc test program
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Tue, 07 May 2024 06:27:20 +0000 |
parents | dfaa8f322a8d |
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 : d4_17pf.c * Purpose : Algebraic codebook decoder * ******************************************************************************** */ /* ******************************************************************************** * MODULE INCLUDE FILE AND VERSION ID ******************************************************************************** */ #include "namespace.h" #include "d4_17pf.h" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "typedef.h" #include "basic_op.h" #include "no_count.h" #include "cnst.h" #include "graytab.h" /* ******************************************************************************** * LOCAL VARIABLES AND TABLES ******************************************************************************** */ #define NB_PULSE 4 /* ******************************************************************************** * PUBLIC PROGRAM CODE ******************************************************************************** */ /************************************************************************* * * FUNCTION: decod_ACELP() * * PURPOSE: Algebraic codebook decoder * *************************************************************************/ void decode_4i40_17bits( Word16 sign, /* i : signs of 4 pulses. */ Word16 index, /* i : Positions of the 4 pulses. */ Word16 cod[] /* o : algebraic (fixed) codebook excitation */ ) { Word16 i, j; Word16 pos[NB_PULSE]; /* Decode the positions */ i = index & 7; logic16 (); i = dgray[i]; move16 (); pos[0] = add(i, shl(i, 2)); /* pos0 =i*5 */ move16 (); index = shr(index, 3); i = index & 7; logic16 (); i = dgray[i]; move16 (); i = add(i, shl(i, 2)); /* pos1 =i*5+1 */ pos[1] = add(i, 1); move16 (); index = shr(index, 3); i = index & 7; logic16 (); i = dgray[i]; move16 (); i = add(i, shl(i, 2)); /* pos2 =i*5+1 */ pos[2] = add(i, 2); move16 (); index = shr(index, 3); j = index & 1; logic16 (); index = shr(index, 1); i = index & 7; logic16 (); i = dgray[i]; move16 (); i = add(i, shl(i, 2)); /* pos3 =i*5+3+j */ i = add(i, 3); pos[3] = 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 (); } else { cod[pos[j]] = -8192; move16 (); } } return; }