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-rw-r--r--codecs/gsm/src/long_term.c955
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diff --git a/codecs/gsm/src/long_term.c b/codecs/gsm/src/long_term.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.
- */
-
-/* $Header$ */
-
-#include <stdio.h>
-#include <assert.h>
-
-#include "private.h"
-
-#include "gsm.h"
-#include "proto.h"
-#ifdef K6OPT
-#include "k6opt.h"
-#endif
-/*
- * 4.2.11 .. 4.2.12 LONG TERM PREDICTOR (LTP) SECTION
- */
-
-
-/*
- * This module computes the LTP gain (bc) and the LTP lag (Nc)
- * for the long term analysis filter. This is done by calculating a
- * maximum of the cross-correlation function between the current
- * sub-segment short term residual signal d[0..39] (output of
- * the short term analysis filter; for simplification the index
- * of this array begins at 0 and ends at 39 for each sub-segment of the
- * RPE-LTP analysis) and the previous reconstructed short term
- * residual signal dp[ -120 .. -1 ]. A dynamic scaling must be
- * performed to avoid overflow.
- */
-
- /* The next procedure exists in six versions. First two integer
- * version (if USE_FLOAT_MUL is not defined); then four floating
- * point versions, twice with proper scaling (USE_FLOAT_MUL defined),
- * once without (USE_FLOAT_MUL and FAST defined, and fast run-time
- * option used). Every pair has first a Cut version (see the -C
- * option to toast or the LTP_CUT option to gsm_option()), then the
- * uncut one. (For a detailed explanation of why this is altogether
- * a bad idea, see Henry Spencer and Geoff Collyer, ``#ifdef Considered
- * Harmful''.)
- */
-
-#ifndef USE_FLOAT_MUL
-
-#ifdef LTP_CUT
-
-static void Cut_Calculation_of_the_LTP_parameters P5((st, d,dp,bc_out,Nc_out),
-
- struct gsm_state * st,
-
- register word * d, /* [0..39] IN */
- register word * dp, /* [-120..-1] IN */
- word * bc_out, /* OUT */
- word * Nc_out /* OUT */
-)
-{
- register int k, lambda;
- word Nc, bc;
- word wt[40];
-
- longword L_result;
- longword L_max, L_power;
- word R, S, dmax, scal, best_k;
- word ltp_cut;
-
- register word temp, wt_k;
-
- /* Search of the optimum scaling of d[0..39].
- */
- dmax = 0;
- for (k = 0; k <= 39; k++) {
- temp = d[k];
- temp = GSM_ABS( temp );
- if (temp > dmax) {
- dmax = temp;
- best_k = k;
- }
- }
- temp = 0;
- if (dmax == 0) scal = 0;
- else {
- assert(dmax > 0);
- temp = gsm_norm( (longword)dmax << 16 );
- }
- if (temp > 6) scal = 0;
- else scal = 6 - temp;
- assert(scal >= 0);
-
- /* Search for the maximum cross-correlation and coding of the LTP lag
- */
- L_max = 0;
- Nc = 40; /* index for the maximum cross-correlation */
- wt_k = SASR(d[best_k], scal);
-
- for (lambda = 40; lambda <= 120; lambda++) {
- L_result = (longword)wt_k * dp[best_k - lambda];
- if (L_result > L_max) {
- Nc = lambda;
- L_max = L_result;
- }
- }
- *Nc_out = Nc;
- L_max <<= 1;
-
- /* Rescaling of L_max
- */
- assert(scal <= 100 && scal >= -100);
- L_max = L_max >> (6 - scal); /* sub(6, scal) */
-
- assert( Nc <= 120 && Nc >= 40);
-
- /* Compute the power of the reconstructed short term residual
- * signal dp[..]
- */
- L_power = 0;
- for (k = 0; k <= 39; k++) {
-
- register longword L_temp;
-
- L_temp = SASR( dp[k - Nc], 3 );
- L_power += L_temp * L_temp;
- }
- L_power <<= 1; /* from L_MULT */
-
- /* Normalization of L_max and L_power
- */
-
- if (L_max <= 0) {
- *bc_out = 0;
- return;
- }
- if (L_max >= L_power) {
- *bc_out = 3;
- return;
- }
-
- temp = gsm_norm( L_power );
-
- R = SASR( L_max << temp, 16 );
- S = SASR( L_power << temp, 16 );
-
- /* Coding of the LTP gain
- */
-
- /* Table 4.3a must be used to obtain the level DLB[i] for the
- * quantization of the LTP gain b to get the coded version bc.
- */
- for (bc = 0; bc <= 2; bc++) if (R <= gsm_mult(S, gsm_DLB[bc])) break;
- *bc_out = bc;
-}
-
-#endif /* LTP_CUT */
-
-static void Calculation_of_the_LTP_parameters P4((d,dp,bc_out,Nc_out),
- register word * d, /* [0..39] IN */
- register word * dp, /* [-120..-1] IN */
- word * bc_out, /* OUT */
- word * Nc_out /* OUT */
-)
-{
- register int k;
-#ifndef K6OPT
- register int lambda;
-#endif
- word Nc, bc;
- word wt[40];
-
- longword L_max, L_power;
- word R, S, dmax, scal;
- register word temp;
-
- /* Search of the optimum scaling of d[0..39].
- */
- dmax = 0;
-
- for (k = 0; k <= 39; k++) {
- temp = d[k];
- temp = GSM_ABS( temp );
- if (temp > dmax) dmax = temp;
- }
-
- temp = 0;
- if (dmax == 0) scal = 0;
- else {
- assert(dmax > 0);
- temp = gsm_norm( (longword)dmax << 16 );
- }
-
- if (temp > 6) scal = 0;
- else scal = 6 - temp;
-
- assert(scal >= 0);
-
- /* Initialization of a working array wt
- */
-
- for (k = 0; k <= 39; k++) wt[k] = SASR( d[k], scal );
-
- /* Search for the maximum cross-correlation and coding of the LTP lag
- */
-# ifdef K6OPT
- L_max = k6maxcc(wt,dp,&Nc);
-# else
- L_max = 0;
- Nc = 40; /* index for the maximum cross-correlation */
-
- for (lambda = 40; lambda <= 120; lambda++) {
-
-# undef STEP
-# define STEP(k) (longword)wt[k] * dp[k - lambda]
-
- register longword L_result;
-
- L_result = STEP(0) ; L_result += STEP(1) ;
- L_result += STEP(2) ; L_result += STEP(3) ;
- L_result += STEP(4) ; L_result += STEP(5) ;
- L_result += STEP(6) ; L_result += STEP(7) ;
- L_result += STEP(8) ; L_result += STEP(9) ;
- L_result += STEP(10) ; L_result += STEP(11) ;
- L_result += STEP(12) ; L_result += STEP(13) ;
- L_result += STEP(14) ; L_result += STEP(15) ;
- L_result += STEP(16) ; L_result += STEP(17) ;
- L_result += STEP(18) ; L_result += STEP(19) ;
- L_result += STEP(20) ; L_result += STEP(21) ;
- L_result += STEP(22) ; L_result += STEP(23) ;
- L_result += STEP(24) ; L_result += STEP(25) ;
- L_result += STEP(26) ; L_result += STEP(27) ;
- L_result += STEP(28) ; L_result += STEP(29) ;
- L_result += STEP(30) ; L_result += STEP(31) ;
- L_result += STEP(32) ; L_result += STEP(33) ;
- L_result += STEP(34) ; L_result += STEP(35) ;
- L_result += STEP(36) ; L_result += STEP(37) ;
- L_result += STEP(38) ; L_result += STEP(39) ;
-
- if (L_result > L_max) {
-
- Nc = lambda;
- L_max = L_result;
- }
- }
-# endif
- *Nc_out = Nc;
-
- L_max <<= 1;
-
- /* Rescaling of L_max
- */
- assert(scal <= 100 && scal >= -100);
- L_max = L_max >> (6 - scal); /* sub(6, scal) */
-
- assert( Nc <= 120 && Nc >= 40);
-
- /* Compute the power of the reconstructed short term residual
- * signal dp[..]
- */
- L_power = 0;
- for (k = 0; k <= 39; k++) {
-
- register longword L_temp;
-
- L_temp = SASR( dp[k - Nc], 3 );
- L_power += L_temp * L_temp;
- }
- L_power <<= 1; /* from L_MULT */
-
- /* Normalization of L_max and L_power
- */
-
- if (L_max <= 0) {
- *bc_out = 0;
- return;
- }
- if (L_max >= L_power) {
- *bc_out = 3;
- return;
- }
-
- temp = gsm_norm( L_power );
-
- R = (word)SASR( L_max << temp, 16 );
- S = (word)SASR( L_power << temp, 16 );
-
- /* Coding of the LTP gain
- */
-
- /* Table 4.3a must be used to obtain the level DLB[i] for the
- * quantization of the LTP gain b to get the coded version bc.
- */
- for (bc = 0; bc <= 2; bc++) if (R <= gsm_mult(S, gsm_DLB[bc])) break;
- *bc_out = bc;
-}
-
-#else /* USE_FLOAT_MUL */
-
-#ifdef LTP_CUT
-
-static void Cut_Calculation_of_the_LTP_parameters P5((st, d,dp,bc_out,Nc_out),
- struct gsm_state * st, /* IN */
- register word * d, /* [0..39] IN */
- register word * dp, /* [-120..-1] IN */
- word * bc_out, /* OUT */
- word * Nc_out /* OUT */
-)
-{
- register int k, lambda;
- word Nc, bc;
- word ltp_cut;
-
- float wt_float[40];
- float dp_float_base[120], * dp_float = dp_float_base + 120;
-
- longword L_max, L_power;
- word R, S, dmax, scal;
- register word temp;
-
- /* Search of the optimum scaling of d[0..39].
- */
- dmax = 0;
-
- for (k = 0; k <= 39; k++) {
- temp = d[k];
- temp = GSM_ABS( temp );
- if (temp > dmax) dmax = temp;
- }
-
- temp = 0;
- if (dmax == 0) scal = 0;
- else {
- assert(dmax > 0);
- temp = gsm_norm( (longword)dmax << 16 );
- }
-
- if (temp > 6) scal = 0;
- else scal = 6 - temp;
-
- assert(scal >= 0);
- ltp_cut = (longword)SASR(dmax, scal) * st->ltp_cut / 100;
-
-
- /* Initialization of a working array wt
- */
-
- for (k = 0; k < 40; k++) {
- register word w = SASR( d[k], scal );
- if (w < 0 ? w > -ltp_cut : w < ltp_cut) {
- wt_float[k] = 0.0;
- }
- else {
- wt_float[k] = w;
- }
- }
- for (k = -120; k < 0; k++) dp_float[k] = dp[k];
-
- /* Search for the maximum cross-correlation and coding of the LTP lag
- */
- L_max = 0;
- Nc = 40; /* index for the maximum cross-correlation */
-
- for (lambda = 40; lambda <= 120; lambda += 9) {
-
- /* Calculate L_result for l = lambda .. lambda + 9.
- */
- register float *lp = dp_float - lambda;
-
- register float W;
- register float a = lp[-8], b = lp[-7], c = lp[-6],
- d = lp[-5], e = lp[-4], f = lp[-3],
- g = lp[-2], h = lp[-1];
- register float E;
- register float S0 = 0, S1 = 0, S2 = 0, S3 = 0, S4 = 0,
- S5 = 0, S6 = 0, S7 = 0, S8 = 0;
-
-# undef STEP
-# define STEP(K, a, b, c, d, e, f, g, h) \
- if ((W = wt_float[K]) != 0.0) { \
- E = W * a; S8 += E; \
- E = W * b; S7 += E; \
- E = W * c; S6 += E; \
- E = W * d; S5 += E; \
- E = W * e; S4 += E; \
- E = W * f; S3 += E; \
- E = W * g; S2 += E; \
- E = W * h; S1 += E; \
- a = lp[K]; \
- E = W * a; S0 += E; } else (a = lp[K])
-
-# define STEP_A(K) STEP(K, a, b, c, d, e, f, g, h)
-# define STEP_B(K) STEP(K, b, c, d, e, f, g, h, a)
-# define STEP_C(K) STEP(K, c, d, e, f, g, h, a, b)
-# define STEP_D(K) STEP(K, d, e, f, g, h, a, b, c)
-# define STEP_E(K) STEP(K, e, f, g, h, a, b, c, d)
-# define STEP_F(K) STEP(K, f, g, h, a, b, c, d, e)
-# define STEP_G(K) STEP(K, g, h, a, b, c, d, e, f)
-# define STEP_H(K) STEP(K, h, a, b, c, d, e, f, g)
-
- STEP_A( 0); STEP_B( 1); STEP_C( 2); STEP_D( 3);
- STEP_E( 4); STEP_F( 5); STEP_G( 6); STEP_H( 7);
-
- STEP_A( 8); STEP_B( 9); STEP_C(10); STEP_D(11);
- STEP_E(12); STEP_F(13); STEP_G(14); STEP_H(15);
-
- STEP_A(16); STEP_B(17); STEP_C(18); STEP_D(19);
- STEP_E(20); STEP_F(21); STEP_G(22); STEP_H(23);
-
- STEP_A(24); STEP_B(25); STEP_C(26); STEP_D(27);
- STEP_E(28); STEP_F(29); STEP_G(30); STEP_H(31);
-
- STEP_A(32); STEP_B(33); STEP_C(34); STEP_D(35);
- STEP_E(36); STEP_F(37); STEP_G(38); STEP_H(39);
-
- if (S0 > L_max) { L_max = S0; Nc = lambda; }
- if (S1 > L_max) { L_max = S1; Nc = lambda + 1; }
- if (S2 > L_max) { L_max = S2; Nc = lambda + 2; }
- if (S3 > L_max) { L_max = S3; Nc = lambda + 3; }
- if (S4 > L_max) { L_max = S4; Nc = lambda + 4; }
- if (S5 > L_max) { L_max = S5; Nc = lambda + 5; }
- if (S6 > L_max) { L_max = S6; Nc = lambda + 6; }
- if (S7 > L_max) { L_max = S7; Nc = lambda + 7; }
- if (S8 > L_max) { L_max = S8; Nc = lambda + 8; }
-
- }
- *Nc_out = Nc;
-
- L_max <<= 1;
-
- /* Rescaling of L_max
- */
- assert(scal <= 100 && scal >= -100);
- L_max = L_max >> (6 - scal); /* sub(6, scal) */
-
- assert( Nc <= 120 && Nc >= 40);
-
- /* Compute the power of the reconstructed short term residual
- * signal dp[..]
- */
- L_power = 0;
- for (k = 0; k <= 39; k++) {
-
- register longword L_temp;
-
- L_temp = SASR( dp[k - Nc], 3 );
- L_power += L_temp * L_temp;
- }
- L_power <<= 1; /* from L_MULT */
-
- /* Normalization of L_max and L_power
- */
-
- if (L_max <= 0) {
- *bc_out = 0;
- return;
- }
- if (L_max >= L_power) {
- *bc_out = 3;
- return;
- }
-
- temp = gsm_norm( L_power );
-
- R = SASR( L_max << temp, 16 );
- S = SASR( L_power << temp, 16 );
-
- /* Coding of the LTP gain
- */
-
- /* Table 4.3a must be used to obtain the level DLB[i] for the
- * quantization of the LTP gain b to get the coded version bc.
- */
- for (bc = 0; bc <= 2; bc++) if (R <= gsm_mult(S, gsm_DLB[bc])) break;
- *bc_out = bc;
-}
-
-#endif /* LTP_CUT */
-
-static void Calculation_of_the_LTP_parameters P4((d,dp,bc_out,Nc_out),
- register word * d, /* [0..39] IN */
- register word * dp, /* [-120..-1] IN */
- word * bc_out, /* OUT */
- word * Nc_out /* OUT */
-)
-{
- register int k, lambda;
- word Nc, bc;
-
- float wt_float[40];
- float dp_float_base[120], * dp_float = dp_float_base + 120;
-
- longword L_max, L_power;
- word R, S, dmax, scal;
- register word temp;
-
- /* Search of the optimum scaling of d[0..39].
- */
- dmax = 0;
-
- for (k = 0; k <= 39; k++) {
- temp = d[k];
- temp = GSM_ABS( temp );
- if (temp > dmax) dmax = temp;
- }
-
- temp = 0;
- if (dmax == 0) scal = 0;
- else {
- assert(dmax > 0);
- temp = gsm_norm( (longword)dmax << 16 );
- }
-
- if (temp > 6) scal = 0;
- else scal = 6 - temp;
-
- assert(scal >= 0);
-
- /* Initialization of a working array wt
- */
-
- for (k = 0; k < 40; k++) wt_float[k] = SASR( d[k], scal );
- for (k = -120; k < 0; k++) dp_float[k] = dp[k];
-
- /* Search for the maximum cross-correlation and coding of the LTP lag
- */
- L_max = 0;
- Nc = 40; /* index for the maximum cross-correlation */
-
- for (lambda = 40; lambda <= 120; lambda += 9) {
-
- /* Calculate L_result for l = lambda .. lambda + 9.
- */
- register float *lp = dp_float - lambda;
-
- register float W;
- register float a = lp[-8], b = lp[-7], c = lp[-6],
- d = lp[-5], e = lp[-4], f = lp[-3],
- g = lp[-2], h = lp[-1];
- register float E;
- register float S0 = 0, S1 = 0, S2 = 0, S3 = 0, S4 = 0,
- S5 = 0, S6 = 0, S7 = 0, S8 = 0;
-
-# undef STEP
-# define STEP(K, a, b, c, d, e, f, g, h) \
- W = wt_float[K]; \
- E = W * a; S8 += E; \
- E = W * b; S7 += E; \
- E = W * c; S6 += E; \
- E = W * d; S5 += E; \
- E = W * e; S4 += E; \
- E = W * f; S3 += E; \
- E = W * g; S2 += E; \
- E = W * h; S1 += E; \
- a = lp[K]; \
- E = W * a; S0 += E
-
-# define STEP_A(K) STEP(K, a, b, c, d, e, f, g, h)
-# define STEP_B(K) STEP(K, b, c, d, e, f, g, h, a)
-# define STEP_C(K) STEP(K, c, d, e, f, g, h, a, b)
-# define STEP_D(K) STEP(K, d, e, f, g, h, a, b, c)
-# define STEP_E(K) STEP(K, e, f, g, h, a, b, c, d)
-# define STEP_F(K) STEP(K, f, g, h, a, b, c, d, e)
-# define STEP_G(K) STEP(K, g, h, a, b, c, d, e, f)
-# define STEP_H(K) STEP(K, h, a, b, c, d, e, f, g)
-
- STEP_A( 0); STEP_B( 1); STEP_C( 2); STEP_D( 3);
- STEP_E( 4); STEP_F( 5); STEP_G( 6); STEP_H( 7);
-
- STEP_A( 8); STEP_B( 9); STEP_C(10); STEP_D(11);
- STEP_E(12); STEP_F(13); STEP_G(14); STEP_H(15);
-
- STEP_A(16); STEP_B(17); STEP_C(18); STEP_D(19);
- STEP_E(20); STEP_F(21); STEP_G(22); STEP_H(23);
-
- STEP_A(24); STEP_B(25); STEP_C(26); STEP_D(27);
- STEP_E(28); STEP_F(29); STEP_G(30); STEP_H(31);
-
- STEP_A(32); STEP_B(33); STEP_C(34); STEP_D(35);
- STEP_E(36); STEP_F(37); STEP_G(38); STEP_H(39);
-
- if (S0 > L_max) { L_max = S0; Nc = lambda; }
- if (S1 > L_max) { L_max = S1; Nc = lambda + 1; }
- if (S2 > L_max) { L_max = S2; Nc = lambda + 2; }
- if (S3 > L_max) { L_max = S3; Nc = lambda + 3; }
- if (S4 > L_max) { L_max = S4; Nc = lambda + 4; }
- if (S5 > L_max) { L_max = S5; Nc = lambda + 5; }
- if (S6 > L_max) { L_max = S6; Nc = lambda + 6; }
- if (S7 > L_max) { L_max = S7; Nc = lambda + 7; }
- if (S8 > L_max) { L_max = S8; Nc = lambda + 8; }
- }
- *Nc_out = Nc;
-
- L_max <<= 1;
-
- /* Rescaling of L_max
- */
- assert(scal <= 100 && scal >= -100);
- L_max = L_max >> (6 - scal); /* sub(6, scal) */
-
- assert( Nc <= 120 && Nc >= 40);
-
- /* Compute the power of the reconstructed short term residual
- * signal dp[..]
- */
- L_power = 0;
- for (k = 0; k <= 39; k++) {
-
- register longword L_temp;
-
- L_temp = SASR( dp[k - Nc], 3 );
- L_power += L_temp * L_temp;
- }
- L_power <<= 1; /* from L_MULT */
-
- /* Normalization of L_max and L_power
- */
-
- if (L_max <= 0) {
- *bc_out = 0;
- return;
- }
- if (L_max >= L_power) {
- *bc_out = 3;
- return;
- }
-
- temp = gsm_norm( L_power );
-
- R = SASR( L_max << temp, 16 );
- S = SASR( L_power << temp, 16 );
-
- /* Coding of the LTP gain
- */
-
- /* Table 4.3a must be used to obtain the level DLB[i] for the
- * quantization of the LTP gain b to get the coded version bc.
- */
- for (bc = 0; bc <= 2; bc++) if (R <= gsm_mult(S, gsm_DLB[bc])) break;
- *bc_out = bc;
-}
-
-#ifdef FAST
-#ifdef LTP_CUT
-
-static void Cut_Fast_Calculation_of_the_LTP_parameters P5((st,
- d,dp,bc_out,Nc_out),
- struct gsm_state * st, /* IN */
- register word * d, /* [0..39] IN */
- register word * dp, /* [-120..-1] IN */
- word * bc_out, /* OUT */
- word * Nc_out /* OUT */
-)
-{
- register int k, lambda;
- register float wt_float;
- word Nc, bc;
- word wt_max, best_k, ltp_cut;
-
- float dp_float_base[120], * dp_float = dp_float_base + 120;
-
- register float L_result, L_max, L_power;
-
- wt_max = 0;
-
- for (k = 0; k < 40; ++k) {
- if ( d[k] > wt_max) wt_max = d[best_k = k];
- else if (-d[k] > wt_max) wt_max = -d[best_k = k];
- }
-
- assert(wt_max >= 0);
- wt_float = (float)wt_max;
-
- for (k = -120; k < 0; ++k) dp_float[k] = (float)dp[k];
-
- /* Search for the maximum cross-correlation and coding of the LTP lag
- */
- L_max = 0;
- Nc = 40; /* index for the maximum cross-correlation */
-
- for (lambda = 40; lambda <= 120; lambda++) {
- L_result = wt_float * dp_float[best_k - lambda];
- if (L_result > L_max) {
- Nc = lambda;
- L_max = L_result;
- }
- }
-
- *Nc_out = Nc;
- if (L_max <= 0.) {
- *bc_out = 0;
- return;
- }
-
- /* Compute the power of the reconstructed short term residual
- * signal dp[..]
- */
- dp_float -= Nc;
- L_power = 0;
- for (k = 0; k < 40; ++k) {
- register float f = dp_float[k];
- L_power += f * f;
- }
-
- if (L_max >= L_power) {
- *bc_out = 3;
- return;
- }
-
- /* Coding of the LTP gain
- * Table 4.3a must be used to obtain the level DLB[i] for the
- * quantization of the LTP gain b to get the coded version bc.
- */
- lambda = L_max / L_power * 32768.;
- for (bc = 0; bc <= 2; ++bc) if (lambda <= gsm_DLB[bc]) break;
- *bc_out = bc;
-}
-
-#endif /* LTP_CUT */
-
-static void Fast_Calculation_of_the_LTP_parameters P4((d,dp,bc_out,Nc_out),
- register word * d, /* [0..39] IN */
- register word * dp, /* [-120..-1] IN */
- word * bc_out, /* OUT */
- word * Nc_out /* OUT */
-)
-{
- register int k, lambda;
- word Nc, bc;
-
- float wt_float[40];
- float dp_float_base[120], * dp_float = dp_float_base + 120;
-
- register float L_max, L_power;
-
- for (k = 0; k < 40; ++k) wt_float[k] = (float)d[k];
- for (k = -120; k < 0; ++k) dp_float[k] = (float)dp[k];
-
- /* Search for the maximum cross-correlation and coding of the LTP lag
- */
- L_max = 0;
- Nc = 40; /* index for the maximum cross-correlation */
-
- for (lambda = 40; lambda <= 120; lambda += 9) {
-
- /* Calculate L_result for l = lambda .. lambda + 9.
- */
- register float *lp = dp_float - lambda;
-
- register float W;
- register float a = lp[-8], b = lp[-7], c = lp[-6],
- d = lp[-5], e = lp[-4], f = lp[-3],
- g = lp[-2], h = lp[-1];
- register float E;
- register float S0 = 0, S1 = 0, S2 = 0, S3 = 0, S4 = 0,
- S5 = 0, S6 = 0, S7 = 0, S8 = 0;
-
-# undef STEP
-# define STEP(K, a, b, c, d, e, f, g, h) \
- W = wt_float[K]; \
- E = W * a; S8 += E; \
- E = W * b; S7 += E; \
- E = W * c; S6 += E; \
- E = W * d; S5 += E; \
- E = W * e; S4 += E; \
- E = W * f; S3 += E; \
- E = W * g; S2 += E; \
- E = W * h; S1 += E; \
- a = lp[K]; \
- E = W * a; S0 += E
-
-# define STEP_A(K) STEP(K, a, b, c, d, e, f, g, h)
-# define STEP_B(K) STEP(K, b, c, d, e, f, g, h, a)
-# define STEP_C(K) STEP(K, c, d, e, f, g, h, a, b)
-# define STEP_D(K) STEP(K, d, e, f, g, h, a, b, c)
-# define STEP_E(K) STEP(K, e, f, g, h, a, b, c, d)
-# define STEP_F(K) STEP(K, f, g, h, a, b, c, d, e)
-# define STEP_G(K) STEP(K, g, h, a, b, c, d, e, f)
-# define STEP_H(K) STEP(K, h, a, b, c, d, e, f, g)
-
- STEP_A( 0); STEP_B( 1); STEP_C( 2); STEP_D( 3);
- STEP_E( 4); STEP_F( 5); STEP_G( 6); STEP_H( 7);
-
- STEP_A( 8); STEP_B( 9); STEP_C(10); STEP_D(11);
- STEP_E(12); STEP_F(13); STEP_G(14); STEP_H(15);
-
- STEP_A(16); STEP_B(17); STEP_C(18); STEP_D(19);
- STEP_E(20); STEP_F(21); STEP_G(22); STEP_H(23);
-
- STEP_A(24); STEP_B(25); STEP_C(26); STEP_D(27);
- STEP_E(28); STEP_F(29); STEP_G(30); STEP_H(31);
-
- STEP_A(32); STEP_B(33); STEP_C(34); STEP_D(35);
- STEP_E(36); STEP_F(37); STEP_G(38); STEP_H(39);
-
- if (S0 > L_max) { L_max = S0; Nc = lambda; }
- if (S1 > L_max) { L_max = S1; Nc = lambda + 1; }
- if (S2 > L_max) { L_max = S2; Nc = lambda + 2; }
- if (S3 > L_max) { L_max = S3; Nc = lambda + 3; }
- if (S4 > L_max) { L_max = S4; Nc = lambda + 4; }
- if (S5 > L_max) { L_max = S5; Nc = lambda + 5; }
- if (S6 > L_max) { L_max = S6; Nc = lambda + 6; }
- if (S7 > L_max) { L_max = S7; Nc = lambda + 7; }
- if (S8 > L_max) { L_max = S8; Nc = lambda + 8; }
- }
- *Nc_out = Nc;
-
- if (L_max <= 0.) {
- *bc_out = 0;
- return;
- }
-
- /* Compute the power of the reconstructed short term residual
- * signal dp[..]
- */
- dp_float -= Nc;
- L_power = 0;
- for (k = 0; k < 40; ++k) {
- register float f = dp_float[k];
- L_power += f * f;
- }
-
- if (L_max >= L_power) {
- *bc_out = 3;
- return;
- }
-
- /* Coding of the LTP gain
- * Table 4.3a must be used to obtain the level DLB[i] for the
- * quantization of the LTP gain b to get the coded version bc.
- */
- lambda = L_max / L_power * 32768.;
- for (bc = 0; bc <= 2; ++bc) if (lambda <= gsm_DLB[bc]) break;
- *bc_out = bc;
-}
-
-#endif /* FAST */
-#endif /* USE_FLOAT_MUL */
-
-
-/* 4.2.12 */
-
-static void Long_term_analysis_filtering P6((bc,Nc,dp,d,dpp,e),
- word bc, /* IN */
- word Nc, /* IN */
- register word * dp, /* previous d [-120..-1] IN */
- register word * d, /* d [0..39] IN */
- register word * dpp, /* estimate [0..39] OUT */
- register word * e /* long term res. signal [0..39] OUT */
-)
-/*
- * In this part, we have to decode the bc parameter to compute
- * the samples of the estimate dpp[0..39]. The decoding of bc needs the
- * use of table 4.3b. The long term residual signal e[0..39]
- * is then calculated to be fed to the RPE encoding section.
- */
-{
- register int k;
-
-# undef STEP
-# define STEP(BP) \
- for (k = 0; k <= 39; k++) { \
- dpp[k] = (word)GSM_MULT_R( BP, dp[k - Nc]); \
- e[k] = GSM_SUB( d[k], dpp[k] ); \
- }
-
- switch (bc) {
- case 0: STEP( 3277 ); break;
- case 1: STEP( 11469 ); break;
- case 2: STEP( 21299 ); break;
- case 3: STEP( 32767 ); break;
- }
-}
-
-void Gsm_Long_Term_Predictor P7((S,d,dp,e,dpp,Nc,bc), /* 4x for 160 samples */
-
- struct gsm_state * S,
-
- word * d, /* [0..39] residual signal IN */
- word * dp, /* [-120..-1] d' IN */
-
- word * e, /* [0..39] OUT */
- word * dpp, /* [0..39] OUT */
- word * Nc, /* correlation lag OUT */
- word * bc /* gain factor OUT */
-)
-{
- assert( d ); assert( dp ); assert( e );
- assert( dpp); assert( Nc ); assert( bc );
-
-#if defined(FAST) && defined(USE_FLOAT_MUL)
- if (S->fast)
-#if defined (LTP_CUT)
- if (S->ltp_cut)
- Cut_Fast_Calculation_of_the_LTP_parameters(S,
- d, dp, bc, Nc);
- else
-#endif /* LTP_CUT */
- Fast_Calculation_of_the_LTP_parameters(d, dp, bc, Nc );
- else
-#endif /* FAST & USE_FLOAT_MUL */
-#ifdef LTP_CUT
- if (S->ltp_cut)
- Cut_Calculation_of_the_LTP_parameters(S, d, dp, bc, Nc);
- else
-#endif
- Calculation_of_the_LTP_parameters(d, dp, bc, Nc);
-
- Long_term_analysis_filtering( *bc, *Nc, dp, d, dpp, e );
-}
-
-/* 4.3.2 */
-void Gsm_Long_Term_Synthesis_Filtering P5((S,Ncr,bcr,erp,drp),
- struct gsm_state * S,
-
- word Ncr,
- word bcr,
- register word * erp, /* [0..39] IN */
- register word * drp /* [-120..-1] IN, [-120..40] OUT */
-)
-/*
- * This procedure uses the bcr and Ncr parameter to realize the
- * long term synthesis filtering. The decoding of bcr needs
- * table 4.3b.
- */
-{
- register int k;
- word brp, drpp, Nr;
-
- /* Check the limits of Nr.
- */
- Nr = Ncr < 40 || Ncr > 120 ? S->nrp : Ncr;
- S->nrp = Nr;
- assert(Nr >= 40 && Nr <= 120);
-
- /* Decoding of the LTP gain bcr
- */
- brp = gsm_QLB[ bcr ];
-
- /* Computation of the reconstructed short term residual
- * signal drp[0..39]
- */
- assert(brp != MIN_WORD);
-
- for (k = 0; k <= 39; k++) {
- drpp = (word)GSM_MULT_R( brp, drp[ k - Nr ] );
- drp[k] = GSM_ADD( erp[k], drpp );
- }
-
- /*
- * Update of the reconstructed short term residual signal
- * drp[ -1..-120 ]
- */
-
- for (k = 0; k <= 119; k++) drp[ -120 + k ] = drp[ -80 + k ];
-}