--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/intercom/gsm/short_te.c	Fri Jun 25 09:57:52 2010 +0200
@@ -0,0 +1,419 @@
+/*
+ * 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: /home/kbs/jutta/src/gsm/gsm-1.0/src/RCS/short_term.c,v 1.1 1992/10/28 00:15:50 jutta Exp $ */
+
+#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;
+  /* register word temp2; -> This is unused */
+  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 );
+   *      }
+   */
+
+#ifdef STEP
+#undef	STEP
+#endif
+
+#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];
+
+#ifdef FILTER
+#undef	FILTER
+#endif
+
+#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];
+
+#ifdef FILTER
+#undef	FILTER
+#endif
+
+#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);
+}