Mercurial > hg > audiostuff
view intercom/ilbc/iCBConstruct.c @ 6:22a74b01a099 default tip
implement more meaningful test program
author | Peter Meerwald <pmeerw@cosy.sbg.ac.at> |
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date | Fri, 25 Jun 2010 16:14:50 +0200 |
parents | 13be24d74cd2 |
children |
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/****************************************************************** 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]; } } } }