15e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh/* 25e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische 35e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * Universitaet Berlin. See the accompanying file "COPYRIGHT" for 45e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * details. THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE. 55e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh */ 65e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 75e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh/* $Header: /tmp_amd/presto/export/kbs/jutta/src/gsm/RCS/code.c,v 1.3 1996/07/02 09:59:05 jutta Exp $ */ 85e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 95e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh#include "config.h" 105e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 115e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 125fa09236b165ef5773a1503349ca8d04fbf82099Elliott Hughes#ifdef HAS_STRING_H 135fa09236b165ef5773a1503349ca8d04fbf82099Elliott Hughes#include <string.h> 145e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh#else 155e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh# include "proto.h" 165e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh extern char * memcpy P((char *, char *, int)); 175e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh#endif 185e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 195e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh#include "private.h" 205e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh#include "gsm.h" 215e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh#include "proto.h" 225e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 235e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh/* 245e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * 4.2 FIXED POINT IMPLEMENTATION OF THE RPE-LTP CODER 255e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh */ 265e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 275e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yehvoid Gsm_Coder P8((S,s,LARc,Nc,bc,Mc,xmaxc,xMc), 285e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 295e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh struct gsm_state * S, 305e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 315e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh word * s, /* [0..159] samples IN */ 325e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 335e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh/* 345e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * The RPE-LTD coder works on a frame by frame basis. The length of 355e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * the frame is equal to 160 samples. Some computations are done 365e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * once per frame to produce at the output of the coder the 375e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * LARc[1..8] parameters which are the coded LAR coefficients and 385e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * also to realize the inverse filtering operation for the entire 395e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * frame (160 samples of signal d[0..159]). These parts produce at 405e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * the output of the coder: 415e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh */ 425e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 435e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh word * LARc, /* [0..7] LAR coefficients OUT */ 445e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 455e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh/* 465e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * Procedure 4.2.11 to 4.2.18 are to be executed four times per 475e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * frame. That means once for each sub-segment RPE-LTP analysis of 485e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * 40 samples. These parts produce at the output of the coder: 495e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh */ 505e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 515e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh word * Nc, /* [0..3] LTP lag OUT */ 525e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh word * bc, /* [0..3] coded LTP gain OUT */ 535e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh word * Mc, /* [0..3] RPE grid selection OUT */ 545e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh word * xmaxc,/* [0..3] Coded maximum amplitude OUT */ 555e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh word * xMc /* [13*4] normalized RPE samples OUT */ 565e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh) 575e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh{ 585e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh int k; 595e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh word * dp = S->dp0 + 120; /* [ -120...-1 ] */ 605e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh word * dpp = dp; /* [ 0...39 ] */ 615e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 625e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh word so[160]; 635e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 645e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh Gsm_Preprocess (S, s, so); 655e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh Gsm_LPC_Analysis (S, so, LARc); 665e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh Gsm_Short_Term_Analysis_Filter (S, LARc, so); 675e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 685e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh for (k = 0; k <= 3; k++, xMc += 13) { 695e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 705e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh Gsm_Long_Term_Predictor ( S, 715e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh so+k*40, /* d [0..39] IN */ 725e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh dp, /* dp [-120..-1] IN */ 735e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh S->e + 5, /* e [0..39] OUT */ 745e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh dpp, /* dpp [0..39] OUT */ 755e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh Nc++, 765e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh bc++); 775e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 785e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh Gsm_RPE_Encoding ( S, 795e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh S->e + 5,/* e ][0..39][ IN/OUT */ 805e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh xmaxc++, Mc++, xMc ); 815e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh /* 825e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * Gsm_Update_of_reconstructed_short_time_residual_signal 835e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh * ( dpp, S->e + 5, dp ); 845e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh */ 855e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 865e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh { register int i; 875e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh register longword ltmp; 885e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh for (i = 0; i <= 39; i++) 895e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh dp[ i ] = GSM_ADD( S->e[5 + i], dpp[i] ); 905e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh } 915e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh dp += 40; 925e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh dpp += 40; 935e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 945e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh } 955e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh (void)memcpy( (char *)S->dp0, (char *)(S->dp0 + 160), 965e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh 120 * sizeof(*S->dp0) ); 975e4516958690b9a1b2c98f88eeecba3edd2dbda4Chia-chi Yeh} 98