Include iLBC source code for distribution with Asterisk

This patch includes the iLBC source code for distribution with Asterisk.
Clarification regarding the iLBC source code was provided by Google, and
the appropriate licenses have been included in the codecs/ilbc folder.

Review: https://reviewboard.asterisk.org/r/1675
Review: https://reviewboard.asterisk.org/r/1649

(closes issue: ASTERISK-18943)
Reporter: Leif Madsen
Tested by: Matt Jordan
........

Merged revisions 351450 from http://svn.asterisk.org/svn/asterisk/branches/1.8
........

Merged revisions 351451 from http://svn.asterisk.org/svn/asterisk/branches/10


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@351452 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 112 insertions, 0 deletions

diff --git a/codecs/ilbc/iCBConstruct.c b/codecs/ilbc/iCBConstruct.c
new file mode 100644
index 000000000..ee9a73ca5
--- /dev/null
+++ b/codecs/ilbc/iCBConstruct.c
@@ -0,0 +1,112 @@
+
+   /******************************************************************
+
+       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];
+               }
+           }
+       }
+   }
+