1RTF_CREATE_BANDPASS_ANALYTIC(3)rtfilter libraryRTF_CREATE_BANDPASS_ANALYTIC(3)
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6 rtf_create_bandpass_analytic - Creates an IIR filter estimating the
7 analytic signal in a bandpass.
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10 #include <rtf_common.h>
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12 hfilter rtf_create_bandpass_analytic(unsigned int nch, int proctype,
13 double fl, double fh,
14 unsigned int num_pole);
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17 rtf_create_chebychev() creates a IIR chebychev filter processing nch
18 channels of data type specified by proctype. The output of the filter
19 is the analytic signal of the bandpassed data between the normalized
20 frequencies fl and fh. The num_pole parameter specifies the number of
21 poles of the Chebychev filter used as the basis of the analytic filter.
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23 A normalized frequency is the ratio between the absolute frequency and
24 the sampling frequency (i.e. a value of 1.0 refers to the sampling fre‐
25 quency).
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27 The Z-transform of this filter has complex coefficients. So like
28 rtf_create_filter(3) the created filter will output complex values
29 keeping the precision specified by proctype.
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31 It is important to note that this filter can quickly become unstable as
32 the number of pole specified increased. Please refers to the authors of
33 the library to know the stability domain (TODO: provides the stability
34 domain here)
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37 Returns the handle to the created filter in case of success, NULL oth‐
38 erwise.
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41 rtf_create_filter(3), rtf_destroy_filter(3)
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48EPFL 2010 RTF_CREATE_BANDPASS_ANALYTIC(3)