
   /******************************************************************

       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);
}
