table.c

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/*
 * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
 * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
 * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
 */

/* $Header: n:\\development/speak_freely/GSM/TABLE.C,v 1.1.1.1 1998/10/15 00:47:39 Administrator Exp $ */

/*	Most of these tables are inlined at their point of use.
 */

/*	4.4 TABLES USED IN THE FIXED POINT IMPLEMENTATION OF THE RPE-LTP
 *		CODER AND DECODER
 *
 *		(Most of them inlined, so watch out.)
 */

#define GSM_TABLE_C
#include "private.h"
#include        "gsm.h"

/*	Table 4.1  Quantization of the Log.-Area Ratios
 */
/* i				 1		2	   3		4	   5	  6 	   7	   8 */
word gsm_A[8]	= {20480, 20480, 20480,  20480,  13964,  15360,   8534,  9036};
word gsm_B[8]	= {    0,	  0,  2048,  -2560, 	94,  -1792,   -341, -1144};
word gsm_MIC[8] = { -32,   -32,   -16,	  -16,	   -8,	   -8,	   -4,	  -4 };
word gsm_MAC[8] = {  31,	31,    15,	   15,		7,		7,		3,	   3 };


/*	Table 4.2  Tabulation  of 1/A[1..8]
 */
word gsm_INVA[8]={ 13107, 13107,  13107, 13107,  19223, 17476,	31454, 29708 };


/*	 Table 4.3a  Decision level of the LTP gain quantizer
 */
/*	bc				  0 		1		  2 		 3					*/
word gsm_DLB[4] = {  6554,	  16384,	26214,	   32767		};


/*	 Table 4.3b   Quantization levels of the LTP gain quantizer
 */
/* bc				  0 		 1		  2 		 3					*/
word gsm_QLB[4] = {  3277,	  11469,	21299,	   32767		};


/*	 Table 4.4	 Coefficients of the weighting filter
 */
/* i				0	   1   2	3	4	   5	  6 	7	8	9	 10  */
word gsm_H[11] = {-134, -374, 0, 2054, 5741, 8192, 5741, 2054, 0, -374, -134 };


/*	 Table 4.5	 Normalized inverse mantissa used to compute xM/xmax 
 */
/* i					0		 1	  2 	 3		4	   5	 6		7	*/
word gsm_NRFAC[8] = { 29128, 26215, 23832, 21846, 20165, 18725, 17476, 16384 };


/*	 Table 4.6	 Normalized direct mantissa used to compute xM/xmax
 */
/* i				  0 	 1		 2		3	   4	  5 	 6		7	*/
word gsm_FAC[8] = { 18431, 20479, 22527, 24575, 26623, 28671, 30719, 32767 };