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rtf_create_bandpass_analytic(3) [debian man page]

RTF_CREATE_BANDPASS_ANALYTIC(3) 				 rtfilter library				   RTF_CREATE_BANDPASS_ANALYTIC(3)

NAME

       rtf_create_bandpass_analytic - Creates an IIR filter estimating the analytic signal in a bandpass.

SYNOPSIS

       #include <rtf_common.h>

       hfilter rtf_create_bandpass_analytic(unsigned int nch, int proctype,
					    double fl, double fh,
					    unsigned int num_pole);

DESCRIPTION

       rtf_create_chebychev()  creates a IIR chebychev filter processing nch channels of data type specified by proctype. The output of the filter
       is the analytic signal of the bandpassed data between the normalized frequencies fl and fh. The num_pole parameter specifies the number	of
       poles of the Chebychev filter used as the basis of the analytic filter.

       A  normalized  frequency is the ratio between the absolute frequency and the sampling frequency (i.e. a value of 1.0 refers to the sampling
       frequency).

       The Z-transform of this filter has complex coefficients. So like rtf_create_filter(3) the created filter will output complex values keeping
       the precision specified by proctype.

       It  is  important  to  note  that  this	filter can quickly become unstable as the number of pole specified increased. Please refers to the
       authors of the library to know the stability domain (TODO: provides the stability domain here)

RETURN VALUE

       Returns the handle to the created filter in case of success, NULL otherwise.

SEE ALSO

       rtf_create_filter(3), rtf_destroy_filter(3)

EPFL
								       2010					   RTF_CREATE_BANDPASS_ANALYTIC(3)

Check Out this Related Man Page

RTF_CREATE_DOWNSAMPLER(3)					 rtfilter library					 RTF_CREATE_DOWNSAMPLER(3)

NAME

       rtf_create_downsampler - Creates downsampling filter

SYNOPSIS

       #include <rtfilter.h>

       hfilter rtf_create_downsampler(unsigned int nch, int type,
				      unsigned int r);

DESCRIPTION

       rtf_create_downsampler()  creates  a  filter that downsamples signals coming from nch channels of type type (see rtf_create_filter(3)) by a
       decimation factor of r (i.e. the sampling frequency of the input will be r times the sampling frequency of the output).	This  is  achieved
       internally by applying a lowpass 4-order Chebychev filter to the input data using a normalized cutoff frequency of 0.8/(2*r) and decimating
       the result every r samples.

RETURN VALUE

       Returns the handle to the created filter in case of success, NULL otherwise.

NOTES

       On the contrary of most other filters, the number of samples returned by rtf_filter(3) is different than the input (as expected)  but  also
       may vary at each call if the number of sample supplied in input is not a multiple of r.

SEE ALSO

       rtf_filter(3), rtf_create_filter(3), rtf_destroy_filter(3)

EPFL
								       2010						 RTF_CREATE_DOWNSAMPLER(3)
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