2c65582b66
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@7221 65c4cc65-6c06-0410-ace0-fbb531ad65f3
74 lines
2.8 KiB
C
74 lines
2.8 KiB
C
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/******************************************************************
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iLBC Speech Coder ANSI-C Source Code
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filter.h
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Copyright (C) The Internet Society (2004).
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All Rights Reserved.
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******************************************************************/
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#ifndef __iLBC_FILTER_H
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#define __iLBC_FILTER_H
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void AllPoleFilter(
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float *InOut, /* (i/o) on entrance InOut[-orderCoef] to
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InOut[-1] contain the state of the
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filter (delayed samples). InOut[0] to
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InOut[lengthInOut-1] contain the filter
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input, on en exit InOut[-orderCoef] to
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InOut[-1] is unchanged and InOut[0] to
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InOut[lengthInOut-1] contain filtered
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samples */
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float *Coef,/* (i) filter coefficients, Coef[0] is assumed
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to be 1.0 */
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int lengthInOut,/* (i) number of input/output samples */
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int orderCoef /* (i) number of filter coefficients */
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);
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void AllZeroFilter(
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float *In, /* (i) In[0] to In[lengthInOut-1] contain
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filter input samples */
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float *Coef,/* (i) filter coefficients (Coef[0] is assumed
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to be 1.0) */
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int lengthInOut,/* (i) number of input/output samples */
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int orderCoef, /* (i) number of filter coefficients */
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float *Out /* (i/o) on entrance Out[-orderCoef] to Out[-1]
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contain the filter state, on exit Out[0]
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to Out[lengthInOut-1] contain filtered
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samples */
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);
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void ZeroPoleFilter(
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float *In, /* (i) In[0] to In[lengthInOut-1] contain filter
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input samples In[-orderCoef] to In[-1]
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contain state of all-zero section */
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float *ZeroCoef,/* (i) filter coefficients for all-zero
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section (ZeroCoef[0] is assumed to
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be 1.0) */
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float *PoleCoef,/* (i) filter coefficients for all-pole section
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(ZeroCoef[0] is assumed to be 1.0) */
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int lengthInOut,/* (i) number of input/output samples */
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int orderCoef, /* (i) number of filter coefficients */
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float *Out /* (i/o) on entrance Out[-orderCoef] to Out[-1]
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contain state of all-pole section. On
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exit Out[0] to Out[lengthInOut-1]
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contain filtered samples */
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);
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void DownSample (
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float *In, /* (i) input samples */
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float *Coef, /* (i) filter coefficients */
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int lengthIn, /* (i) number of input samples */
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float *state, /* (i) filter state */
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float *Out /* (o) downsampled output */
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);
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#endif
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