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Diffstat (limited to 'trunk/codecs/ilbc/StateSearchW.c')
| -rw-r--r-- | trunk/codecs/ilbc/StateSearchW.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/trunk/codecs/ilbc/StateSearchW.c b/trunk/codecs/ilbc/StateSearchW.c new file mode 100644 index 000000000..b87b9f3c6 --- /dev/null +++ b/trunk/codecs/ilbc/StateSearchW.c @@ -0,0 +1,194 @@ + +/****************************************************************** + + 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 "StateSearchW.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); +} + + |