Asterisk - The Open Source Telephony Project  21.4.1
LPCdecode.h
1 
2  /******************************************************************
3 
4  iLBC Speech Coder ANSI-C Source Code
5 
6  LPC_decode.h
7 
8  Copyright (C) The Internet Society (2004).
9  All Rights Reserved.
10 
11  ******************************************************************/
12 
13  #ifndef __iLBC_LPC_DECODE_H
14  #define __iLBC_LPC_DECODE_H
15 
16  void LSFinterpolate2a_dec(
17  float *a, /* (o) lpc coefficients for a sub-frame */
18  float *lsf1, /* (i) first lsf coefficient vector */
19  float *lsf2, /* (i) second lsf coefficient vector */
20  float coef, /* (i) interpolation weight */
21  int length /* (i) length of lsf vectors */
22  );
23 
24  void SimplelsfDEQ(
25  float *lsfdeq, /* (o) dequantized lsf coefficients */
26  int *index, /* (i) quantization index */
27  int lpc_n /* (i) number of LPCs */
28  );
29 
30  void DecoderInterpolateLSF(
31  float *syntdenum, /* (o) synthesis filter coefficients */
32  float *weightdenum, /* (o) weighting denumerator
33  coefficients */
34  float *lsfdeq, /* (i) dequantized lsf coefficients */
35  int length, /* (i) length of lsf coefficient vector */
36  iLBC_Dec_Inst_t *iLBCdec_inst
37  /* (i) the decoder state structure */
38  );
39 
40  #endif