--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/intercom/ilbc/iCBConstruct.c	Fri Jun 25 09:57:52 2010 +0200
@@ -0,0 +1,109 @@
+
+   /******************************************************************
+
+       iLBC Speech Coder ANSI-C Source Code
+
+       iCBConstruct.c
+
+       Copyright (C) The Internet Society (2004).
+       All Rights Reserved.
+
+   ******************************************************************/
+
+#include <math.h>
+
+#include "iLBC_define.h"
+#include "gainquant.h"
+#include "getCBvec.h"
+
+   /*----------------------------------------------------------------*
+    *  Convert the codebook indexes to make the search easier
+    *---------------------------------------------------------------*/
+
+
+
+
+
+
+void index_conv_enc(int *index  /* (i/o) Codebook indexes */
+  )
+{
+  int k;
+
+  for (k = 1; k < CB_NSTAGES; k++) {
+
+    if ((index[k] >= 108) && (index[k] < 172)) {
+      index[k] -= 64;
+    } else if (index[k] >= 236) {
+      index[k] -= 128;
+    } else {
+      /* ERROR */
+    }
+  }
+}
+
+void index_conv_dec(int *index  /* (i/o) Codebook indexes */
+  )
+{
+  int k;
+
+  for (k = 1; k < CB_NSTAGES; k++) {
+
+    if ((index[k] >= 44) && (index[k] < 108)) {
+      index[k] += 64;
+    } else if ((index[k] >= 108) && (index[k] < 128)) {
+      index[k] += 128;
+    } else {
+      /* ERROR */
+    }
+  }
+}
+
+   /*----------------------------------------------------------------*
+    *  Construct decoded vector from codebook and gains.
+    *---------------------------------------------------------------*/
+
+void iCBConstruct(float *decvector,     /* (o) Decoded vector */
+  int *index,                   /* (i) Codebook indices */
+  int *gain_index,              /* (i) Gain quantization indices */
+  float *mem,                   /* (i) Buffer for codevector construction */
+  int lMem,                     /* (i) Length of buffer */
+  int veclen,                   /* (i) Length of vector */
+  int nStages                   /* (i) Number of codebook stages */
+  )
+{
+  int j, k;
+
+
+
+
+
+  float gain[CB_NSTAGES];
+  float cbvec[SUBL];
+
+  /* gain de-quantization */
+
+  gain[0] = gaindequant(gain_index[0], 1.0, 32);
+  if (nStages > 1) {
+    gain[1] = gaindequant(gain_index[1], (float) fabs(gain[0]), 16);
+  }
+  if (nStages > 2) {
+    gain[2] = gaindequant(gain_index[2], (float) fabs(gain[1]), 8);
+  }
+
+  /* codebook vector construction and construction of
+     total vector */
+
+  getCBvec(cbvec, mem, index[0], lMem, veclen);
+  for (j = 0; j < veclen; j++) {
+    decvector[j] = gain[0] * cbvec[j];
+  }
+  if (nStages > 1) {
+    for (k = 1; k < nStages; k++) {
+      getCBvec(cbvec, mem, index[k], lMem, veclen);
+      for (j = 0; j < veclen; j++) {
+        decvector[j] += gain[k] * cbvec[j];
+      }
+    }
+  }
+}