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, 211 insertions, 0 deletions

diff --git a/codecs/ilbc/StateSearchW.c b/codecs/ilbc/StateSearchW.c
new file mode 100644
index 000000000..1eeee936c
--- /dev/null
+++ b/codecs/ilbc/StateSearchW.c
@@ -0,0 +1,211 @@
+
+   /******************************************************************
+
+       iLBC Speech Coder ANSI-C Source Code
+
+       StateSearchW.c
+
+       Copyright (C) The Internet Society (2004).
+       All Rights Reserved.
+
+   ******************************************************************/
+
+   #include <math.h>
+   #include <string.h>
+
+   #include "iLBC_define.h"
+   #include "constants.h"
+   #include "filter.h"
+   #include "helpfun.h"
+
+   /*----------------------------------------------------------------*
+    *  predictive noise shaping encoding of scaled start state
+    *  (subrutine for StateSearchW)
+    *---------------------------------------------------------------*/
+
+   void AbsQuantW(
+       iLBC_Enc_Inst_t *iLBCenc_inst,
+                           /* (i) Encoder instance */
+       float *in,          /* (i) vector to encode */
+       float *syntDenum,   /* (i) denominator of synthesis filter */
+       float *weightDenum, /* (i) denominator of weighting filter */
+       int *out,           /* (o) vector of quantizer indexes */
+       int len,        /* (i) length of vector to encode and
+                                  vector of quantizer indexes */
+       int state_first     /* (i) position of start state in the
+                                  80 vec */
+   ){
+       float *syntOut;
+       float syntOutBuf[LPC_FILTERORDER+STATE_SHORT_LEN_30MS];
+       float toQ, xq;
+       int n;
+       int index;
+
+       /* initialization of buffer for filtering */
+
+       memset(syntOutBuf, 0, LPC_FILTERORDER*sizeof(float));
+
+
+
+
+
+
+       /* initialization of pointer for filtering */
+
+       syntOut = &syntOutBuf[LPC_FILTERORDER];
+
+       /* synthesis and weighting filters on input */
+
+       if (state_first) {
+           AllPoleFilter (in, weightDenum, SUBL, LPC_FILTERORDER);
+       } else {
+           AllPoleFilter (in, weightDenum,
+               iLBCenc_inst->state_short_len-SUBL,
+               LPC_FILTERORDER);
+       }
+
+       /* encoding loop */
+
+       for (n=0; n<len; n++) {
+
+           /* time update of filter coefficients */
+
+           if ((state_first)&&(n==SUBL)){
+               syntDenum += (LPC_FILTERORDER+1);
+               weightDenum += (LPC_FILTERORDER+1);
+
+               /* synthesis and weighting filters on input */
+               AllPoleFilter (&in[n], weightDenum, len-n,
+                   LPC_FILTERORDER);
+
+           } else if ((state_first==0)&&
+               (n==(iLBCenc_inst->state_short_len-SUBL))) {
+               syntDenum += (LPC_FILTERORDER+1);
+               weightDenum += (LPC_FILTERORDER+1);
+
+               /* synthesis and weighting filters on input */
+               AllPoleFilter (&in[n], weightDenum, len-n,
+                   LPC_FILTERORDER);
+
+           }
+
+           /* prediction of synthesized and weighted input */
+
+           syntOut[n] = 0.0;
+           AllPoleFilter (&syntOut[n], weightDenum, 1,
+               LPC_FILTERORDER);
+
+           /* quantization */
+
+           toQ = in[n]-syntOut[n];
+
+
+
+
+
+           sort_sq(&xq, &index, toQ, state_sq3Tbl, 8);
+           out[n]=index;
+           syntOut[n] = state_sq3Tbl[out[n]];
+
+           /* update of the prediction filter */
+
+           AllPoleFilter(&syntOut[n], weightDenum, 1,
+               LPC_FILTERORDER);
+       }
+   }
+
+   /*----------------------------------------------------------------*
+    *  encoding of start state
+    *---------------------------------------------------------------*/
+
+   void StateSearchW(
+       iLBC_Enc_Inst_t *iLBCenc_inst,
+                           /* (i) Encoder instance */
+       float *residual,/* (i) target residual vector */
+       float *syntDenum,   /* (i) lpc synthesis filter */
+       float *weightDenum, /* (i) weighting filter denuminator */
+       int *idxForMax,     /* (o) quantizer index for maximum
+                                  amplitude */
+       int *idxVec,    /* (o) vector of quantization indexes */
+       int len,        /* (i) length of all vectors */
+       int state_first     /* (i) position of start state in the
+                                  80 vec */
+   ){
+       float dtmp, maxVal;
+       float tmpbuf[LPC_FILTERORDER+2*STATE_SHORT_LEN_30MS];
+       float *tmp, numerator[1+LPC_FILTERORDER];
+       float foutbuf[LPC_FILTERORDER+2*STATE_SHORT_LEN_30MS], *fout;
+       int k;
+       float qmax, scal;
+
+       /* initialization of buffers and filter coefficients */
+
+       memset(tmpbuf, 0, LPC_FILTERORDER*sizeof(float));
+       memset(foutbuf, 0, LPC_FILTERORDER*sizeof(float));
+       for (k=0; k<LPC_FILTERORDER; k++) {
+           numerator[k]=syntDenum[LPC_FILTERORDER-k];
+       }
+       numerator[LPC_FILTERORDER]=syntDenum[0];
+       tmp = &tmpbuf[LPC_FILTERORDER];
+       fout = &foutbuf[LPC_FILTERORDER];
+
+       /* circular convolution with the all-pass filter */
+
+
+
+
+
+
+       memcpy(tmp, residual, len*sizeof(float));
+       memset(tmp+len, 0, len*sizeof(float));
+       ZeroPoleFilter(tmp, numerator, syntDenum, 2*len,
+           LPC_FILTERORDER, fout);
+       for (k=0; k<len; k++) {
+           fout[k] += fout[k+len];
+       }
+
+       /* identification of the maximum amplitude value */
+
+       maxVal = fout[0];
+       for (k=1; k<len; k++) {
+
+           if (fout[k]*fout[k] > maxVal*maxVal){
+               maxVal = fout[k];
+           }
+       }
+       maxVal=(float)fabs(maxVal);
+
+       /* encoding of the maximum amplitude value */
+
+       if (maxVal < 10.0) {
+           maxVal = 10.0;
+       }
+       maxVal = (float)log10(maxVal);
+       sort_sq(&dtmp, idxForMax, maxVal, state_frgqTbl, 64);
+
+       /* decoding of the maximum amplitude representation value,
+          and corresponding scaling of start state */
+
+       maxVal=state_frgqTbl[*idxForMax];
+       qmax = (float)pow(10,maxVal);
+       scal = (float)(4.5)/qmax;
+       for (k=0; k<len; k++){
+           fout[k] *= scal;
+       }
+
+       /* predictive noise shaping encoding of scaled start state */
+
+       AbsQuantW(iLBCenc_inst, fout,syntDenum,
+           weightDenum,idxVec, len, state_first);
+   }
+
+
+
+
+
+
+
+
+
+
+