74 lines
2.8 KiB
C
74 lines
2.8 KiB
C
|
|
/******************************************************************
|
|
|
|
iLBC Speech Coder ANSI-C Source Code
|
|
|
|
filter.h
|
|
|
|
Copyright (C) The Internet Society (2004).
|
|
All Rights Reserved.
|
|
|
|
******************************************************************/
|
|
|
|
#ifndef __iLBC_FILTER_H
|
|
#define __iLBC_FILTER_H
|
|
|
|
void AllPoleFilter(
|
|
float *InOut, /* (i/o) on entrance InOut[-orderCoef] to
|
|
InOut[-1] contain the state of the
|
|
filter (delayed samples). InOut[0] to
|
|
InOut[lengthInOut-1] contain the filter
|
|
input, on en exit InOut[-orderCoef] to
|
|
InOut[-1] is unchanged and InOut[0] to
|
|
InOut[lengthInOut-1] contain filtered
|
|
samples */
|
|
float *Coef,/* (i) filter coefficients, Coef[0] is assumed
|
|
to be 1.0 */
|
|
int lengthInOut,/* (i) number of input/output samples */
|
|
int orderCoef /* (i) number of filter coefficients */
|
|
);
|
|
|
|
|
|
|
|
void AllZeroFilter(
|
|
float *In, /* (i) In[0] to In[lengthInOut-1] contain
|
|
filter input samples */
|
|
float *Coef,/* (i) filter coefficients (Coef[0] is assumed
|
|
to be 1.0) */
|
|
int lengthInOut,/* (i) number of input/output samples */
|
|
int orderCoef, /* (i) number of filter coefficients */
|
|
float *Out /* (i/o) on entrance Out[-orderCoef] to Out[-1]
|
|
contain the filter state, on exit Out[0]
|
|
to Out[lengthInOut-1] contain filtered
|
|
samples */
|
|
);
|
|
|
|
void ZeroPoleFilter(
|
|
float *In, /* (i) In[0] to In[lengthInOut-1] contain filter
|
|
input samples In[-orderCoef] to In[-1]
|
|
contain state of all-zero section */
|
|
float *ZeroCoef,/* (i) filter coefficients for all-zero
|
|
section (ZeroCoef[0] is assumed to
|
|
be 1.0) */
|
|
float *PoleCoef,/* (i) filter coefficients for all-pole section
|
|
(ZeroCoef[0] is assumed to be 1.0) */
|
|
int lengthInOut,/* (i) number of input/output samples */
|
|
int orderCoef, /* (i) number of filter coefficients */
|
|
float *Out /* (i/o) on entrance Out[-orderCoef] to Out[-1]
|
|
contain state of all-pole section. On
|
|
exit Out[0] to Out[lengthInOut-1]
|
|
contain filtered samples */
|
|
);
|
|
|
|
void DownSample (
|
|
float *In, /* (i) input samples */
|
|
float *Coef, /* (i) filter coefficients */
|
|
int lengthIn, /* (i) number of input samples */
|
|
float *state, /* (i) filter state */
|
|
float *Out /* (o) downsampled output */
|
|
);
|
|
|
|
#endif
|
|
|
|
|