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authormarkster <markster@f38db490-d61c-443f-a65b-d21fe96a405b>1999-11-15 06:08:50 +0000
committermarkster <markster@f38db490-d61c-443f-a65b-d21fe96a405b>1999-11-15 06:08:50 +0000
commit95986cb001dda2bc2fdd92463ea48bd8acf96d6b (patch)
treeb3769d333429e596524dc78e3841008f7af2ae74 /codecs/gsm/src/short_term.c
parenta4717bc16b9a517a9685ee579aeb35af8933ce1c (diff)
Version 0.1.0 from FTP
git-svn-id: http://svn.digium.com/svn/asterisk/trunk@23 f38db490-d61c-443f-a65b-d21fe96a405b
Diffstat (limited to 'codecs/gsm/src/short_term.c')
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1 files changed, 429 insertions, 0 deletions
diff --git a/codecs/gsm/src/short_term.c b/codecs/gsm/src/short_term.c
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+++ b/codecs/gsm/src/short_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"
+
+/*
+ * SHORT TERM ANALYSIS FILTERING SECTION
+ */
+
+/* 4.2.8 */
+
+static void Decoding_of_the_coded_Log_Area_Ratios P2((LARc,LARpp),
+ word * LARc, /* coded log area ratio [0..7] IN */
+ word * LARpp) /* out: decoded .. */
+{
+ register word temp1 /* , temp2 */;
+ register long ltmp; /* for GSM_ADD */
+
+ /* This procedure requires for efficient implementation
+ * two tables.
+ *
+ * INVA[1..8] = integer( (32768 * 8) / real_A[1..8])
+ * MIC[1..8] = minimum value of the LARc[1..8]
+ */
+
+ /* Compute the LARpp[1..8]
+ */
+
+ /* for (i = 1; i <= 8; i++, B++, MIC++, INVA++, LARc++, LARpp++) {
+ *
+ * temp1 = GSM_ADD( *LARc, *MIC ) << 10;
+ * temp2 = *B << 1;
+ * temp1 = GSM_SUB( temp1, temp2 );
+ *
+ * assert(*INVA != MIN_WORD);
+ *
+ * temp1 = GSM_MULT_R( *INVA, temp1 );
+ * *LARpp = GSM_ADD( temp1, temp1 );
+ * }
+ */
+
+#undef STEP
+#define STEP( B, MIC, INVA ) \
+ temp1 = GSM_ADD( *LARc++, MIC ) << 10; \
+ temp1 = GSM_SUB( temp1, B << 1 ); \
+ temp1 = GSM_MULT_R( INVA, temp1 ); \
+ *LARpp++ = GSM_ADD( temp1, temp1 );
+
+ STEP( 0, -32, 13107 );
+ STEP( 0, -32, 13107 );
+ STEP( 2048, -16, 13107 );
+ STEP( -2560, -16, 13107 );
+
+ STEP( 94, -8, 19223 );
+ STEP( -1792, -8, 17476 );
+ STEP( -341, -4, 31454 );
+ STEP( -1144, -4, 29708 );
+
+ /* NOTE: the addition of *MIC is used to restore
+ * the sign of *LARc.
+ */
+}
+
+/* 4.2.9 */
+/* Computation of the quantized reflection coefficients
+ */
+
+/* 4.2.9.1 Interpolation of the LARpp[1..8] to get the LARp[1..8]
+ */
+
+/*
+ * Within each frame of 160 analyzed speech samples the short term
+ * analysis and synthesis filters operate with four different sets of
+ * coefficients, derived from the previous set of decoded LARs(LARpp(j-1))
+ * and the actual set of decoded LARs (LARpp(j))
+ *
+ * (Initial value: LARpp(j-1)[1..8] = 0.)
+ */
+
+static void Coefficients_0_12 P3((LARpp_j_1, LARpp_j, LARp),
+ register word * LARpp_j_1,
+ register word * LARpp_j,
+ register word * LARp)
+{
+ register int i;
+ register longword ltmp;
+
+ for (i = 1; i <= 8; i++, LARp++, LARpp_j_1++, LARpp_j++) {
+ *LARp = GSM_ADD( SASR( *LARpp_j_1, 2 ), SASR( *LARpp_j, 2 ));
+ *LARp = GSM_ADD( *LARp, SASR( *LARpp_j_1, 1));
+ }
+}
+
+static void Coefficients_13_26 P3((LARpp_j_1, LARpp_j, LARp),
+ register word * LARpp_j_1,
+ register word * LARpp_j,
+ register word * LARp)
+{
+ register int i;
+ register longword ltmp;
+ for (i = 1; i <= 8; i++, LARpp_j_1++, LARpp_j++, LARp++) {
+ *LARp = GSM_ADD( SASR( *LARpp_j_1, 1), SASR( *LARpp_j, 1 ));
+ }
+}
+
+static void Coefficients_27_39 P3((LARpp_j_1, LARpp_j, LARp),
+ register word * LARpp_j_1,
+ register word * LARpp_j,
+ register word * LARp)
+{
+ register int i;
+ register longword ltmp;
+
+ for (i = 1; i <= 8; i++, LARpp_j_1++, LARpp_j++, LARp++) {
+ *LARp = GSM_ADD( SASR( *LARpp_j_1, 2 ), SASR( *LARpp_j, 2 ));
+ *LARp = GSM_ADD( *LARp, SASR( *LARpp_j, 1 ));
+ }
+}
+
+
+static void Coefficients_40_159 P2((LARpp_j, LARp),
+ register word * LARpp_j,
+ register word * LARp)
+{
+ register int i;
+
+ for (i = 1; i <= 8; i++, LARp++, LARpp_j++)
+ *LARp = *LARpp_j;
+}
+
+/* 4.2.9.2 */
+
+static void LARp_to_rp P1((LARp),
+ register word * LARp) /* [0..7] IN/OUT */
+/*
+ * The input of this procedure is the interpolated LARp[0..7] array.
+ * The reflection coefficients, rp[i], are used in the analysis
+ * filter and in the synthesis filter.
+ */
+{
+ register int i;
+ register word temp;
+ register longword ltmp;
+
+ for (i = 1; i <= 8; i++, LARp++) {
+
+ /* temp = GSM_ABS( *LARp );
+ *
+ * if (temp < 11059) temp <<= 1;
+ * else if (temp < 20070) temp += 11059;
+ * else temp = GSM_ADD( temp >> 2, 26112 );
+ *
+ * *LARp = *LARp < 0 ? -temp : temp;
+ */
+
+ if (*LARp < 0) {
+ temp = *LARp == MIN_WORD ? MAX_WORD : -(*LARp);
+ *LARp = - ((temp < 11059) ? temp << 1
+ : ((temp < 20070) ? temp + 11059
+ : GSM_ADD( temp >> 2, 26112 )));
+ } else {
+ temp = *LARp;
+ *LARp = (temp < 11059) ? temp << 1
+ : ((temp < 20070) ? temp + 11059
+ : GSM_ADD( temp >> 2, 26112 ));
+ }
+ }
+}
+
+
+/* 4.2.10 */
+static void Short_term_analysis_filtering P4((S,rp,k_n,s),
+ struct gsm_state * S,
+ register word * rp, /* [0..7] IN */
+ register int k_n, /* k_end - k_start */
+ register word * s /* [0..n-1] IN/OUT */
+)
+/*
+ * This procedure computes the short term residual signal d[..] to be fed
+ * to the RPE-LTP loop from the s[..] signal and from the local rp[..]
+ * array (quantized reflection coefficients). As the call of this
+ * procedure can be done in many ways (see the interpolation of the LAR
+ * coefficient), it is assumed that the computation begins with index
+ * k_start (for arrays d[..] and s[..]) and stops with index k_end
+ * (k_start and k_end are defined in 4.2.9.1). This procedure also
+ * needs to keep the array u[0..7] in memory for each call.
+ */
+{
+ register word * u = S->u;
+ register int i;
+ register word di, zzz, ui, sav, rpi;
+ register longword ltmp;
+
+ for (; k_n--; s++) {
+
+ di = sav = *s;
+
+ for (i = 0; i < 8; i++) { /* YYY */
+
+ ui = u[i];
+ rpi = rp[i];
+ u[i] = sav;
+
+ zzz = GSM_MULT_R(rpi, di);
+ sav = GSM_ADD( ui, zzz);
+
+ zzz = GSM_MULT_R(rpi, ui);
+ di = GSM_ADD( di, zzz );
+ }
+
+ *s = di;
+ }
+}
+
+#if defined(USE_FLOAT_MUL) && defined(FAST)
+
+static void Fast_Short_term_analysis_filtering P4((S,rp,k_n,s),
+ struct gsm_state * S,
+ register word * rp, /* [0..7] IN */
+ register int k_n, /* k_end - k_start */
+ register word * s /* [0..n-1] IN/OUT */
+)
+{
+ register word * u = S->u;
+ register int i;
+
+ float uf[8],
+ rpf[8];
+
+ register float scalef = 3.0517578125e-5;
+ register float sav, di, temp;
+
+ for (i = 0; i < 8; ++i) {
+ uf[i] = u[i];
+ rpf[i] = rp[i] * scalef;
+ }
+ for (; k_n--; s++) {
+ sav = di = *s;
+ for (i = 0; i < 8; ++i) {
+ register float rpfi = rpf[i];
+ register float ufi = uf[i];
+
+ uf[i] = sav;
+ temp = rpfi * di + ufi;
+ di += rpfi * ufi;
+ sav = temp;
+ }
+ *s = di;
+ }
+ for (i = 0; i < 8; ++i) u[i] = uf[i];
+}
+#endif /* ! (defined (USE_FLOAT_MUL) && defined (FAST)) */
+
+static void Short_term_synthesis_filtering P5((S,rrp,k,wt,sr),
+ struct gsm_state * S,
+ register word * rrp, /* [0..7] IN */
+ register int k, /* k_end - k_start */
+ register word * wt, /* [0..k-1] IN */
+ register word * sr /* [0..k-1] OUT */
+)
+{
+ register word * v = S->v;
+ register int i;
+ register word sri, tmp1, tmp2;
+ register longword ltmp; /* for GSM_ADD & GSM_SUB */
+
+ while (k--) {
+ sri = *wt++;
+ for (i = 8; i--;) {
+
+ /* sri = GSM_SUB( sri, gsm_mult_r( rrp[i], v[i] ) );
+ */
+ tmp1 = rrp[i];
+ tmp2 = v[i];
+ tmp2 = ( tmp1 == MIN_WORD && tmp2 == MIN_WORD
+ ? MAX_WORD
+ : 0x0FFFF & (( (longword)tmp1 * (longword)tmp2
+ + 16384) >> 15)) ;
+
+ sri = GSM_SUB( sri, tmp2 );
+
+ /* v[i+1] = GSM_ADD( v[i], gsm_mult_r( rrp[i], sri ) );
+ */
+ tmp1 = ( tmp1 == MIN_WORD && sri == MIN_WORD
+ ? MAX_WORD
+ : 0x0FFFF & (( (longword)tmp1 * (longword)sri
+ + 16384) >> 15)) ;
+
+ v[i+1] = GSM_ADD( v[i], tmp1);
+ }
+ *sr++ = v[0] = sri;
+ }
+}
+
+
+#if defined(FAST) && defined(USE_FLOAT_MUL)
+
+static void Fast_Short_term_synthesis_filtering P5((S,rrp,k,wt,sr),
+ struct gsm_state * S,
+ register word * rrp, /* [0..7] IN */
+ register int k, /* k_end - k_start */
+ register word * wt, /* [0..k-1] IN */
+ register word * sr /* [0..k-1] OUT */
+)
+{
+ register word * v = S->v;
+ register int i;
+
+ float va[9], rrpa[8];
+ register float scalef = 3.0517578125e-5, temp;
+
+ for (i = 0; i < 8; ++i) {
+ va[i] = v[i];
+ rrpa[i] = (float)rrp[i] * scalef;
+ }
+ while (k--) {
+ register float sri = *wt++;
+ for (i = 8; i--;) {
+ sri -= rrpa[i] * va[i];
+ if (sri < -32768.) sri = -32768.;
+ else if (sri > 32767.) sri = 32767.;
+
+ temp = va[i] + rrpa[i] * sri;
+ if (temp < -32768.) temp = -32768.;
+ else if (temp > 32767.) temp = 32767.;
+ va[i+1] = temp;
+ }
+ *sr++ = va[0] = sri;
+ }
+ for (i = 0; i < 9; ++i) v[i] = va[i];
+}
+
+#endif /* defined(FAST) && defined(USE_FLOAT_MUL) */
+
+void Gsm_Short_Term_Analysis_Filter P3((S,LARc,s),
+
+ struct gsm_state * S,
+
+ word * LARc, /* coded log area ratio [0..7] IN */
+ word * s /* signal [0..159] IN/OUT */
+)
+{
+ word * LARpp_j = S->LARpp[ S->j ];
+ word * LARpp_j_1 = S->LARpp[ S->j ^= 1 ];
+
+ word LARp[8];
+
+#undef FILTER
+#if defined(FAST) && defined(USE_FLOAT_MUL)
+# define FILTER (* (S->fast \
+ ? Fast_Short_term_analysis_filtering \
+ : Short_term_analysis_filtering ))
+
+#else
+# define FILTER Short_term_analysis_filtering
+#endif
+
+ Decoding_of_the_coded_Log_Area_Ratios( LARc, LARpp_j );
+
+ Coefficients_0_12( LARpp_j_1, LARpp_j, LARp );
+ LARp_to_rp( LARp );
+ FILTER( S, LARp, 13, s);
+
+ Coefficients_13_26( LARpp_j_1, LARpp_j, LARp);
+ LARp_to_rp( LARp );
+ FILTER( S, LARp, 14, s + 13);
+
+ Coefficients_27_39( LARpp_j_1, LARpp_j, LARp);
+ LARp_to_rp( LARp );
+ FILTER( S, LARp, 13, s + 27);
+
+ Coefficients_40_159( LARpp_j, LARp);
+ LARp_to_rp( LARp );
+ FILTER( S, LARp, 120, s + 40);
+}
+
+void Gsm_Short_Term_Synthesis_Filter P4((S, LARcr, wt, s),
+ struct gsm_state * S,
+
+ word * LARcr, /* received log area ratios [0..7] IN */
+ word * wt, /* received d [0..159] IN */
+
+ word * s /* signal s [0..159] OUT */
+)
+{
+ word * LARpp_j = S->LARpp[ S->j ];
+ word * LARpp_j_1 = S->LARpp[ S->j ^=1 ];
+
+ word LARp[8];
+
+#undef FILTER
+#if defined(FAST) && defined(USE_FLOAT_MUL)
+
+# define FILTER (* (S->fast \
+ ? Fast_Short_term_synthesis_filtering \
+ : Short_term_synthesis_filtering ))
+#else
+# define FILTER Short_term_synthesis_filtering
+#endif
+
+ Decoding_of_the_coded_Log_Area_Ratios( LARcr, LARpp_j );
+
+ Coefficients_0_12( LARpp_j_1, LARpp_j, LARp );
+ LARp_to_rp( LARp );
+ FILTER( S, LARp, 13, wt, s );
+
+ Coefficients_13_26( LARpp_j_1, LARpp_j, LARp);
+ LARp_to_rp( LARp );
+ FILTER( S, LARp, 14, wt + 13, s + 13 );
+
+ Coefficients_27_39( LARpp_j_1, LARpp_j, LARp);
+ LARp_to_rp( LARp );
+ FILTER( S, LARp, 13, wt + 27, s + 27 );
+
+ Coefficients_40_159( LARpp_j, LARp );
+ LARp_to_rp( LARp );
+ FILTER(S, LARp, 120, wt + 40, s + 40);
+}