rtf_create_chebychev(3) [debian man page]

RTF_CREATE_CHEBYCHEV(3) 					 rtfilter library					   RTF_CREATE_CHEBYCHEV(3)

NAME

       rtf_create_chebychev, rtf_create_butterworth - Creates IIR Chebychev and Butterwoth filters

SYNOPSIS

       #include <rtf_common.h>

       hfilter rtf_create_chebychev(unsigned int nchann, int proctype,
				    double fc, unsigned int num_pole,
				    int highpass, double r);
       hfilter rtf_create_butterworth(unsigned int nchann, int proctype,
				      double fc, unsigned int num_pole,
				      int highpass);

DESCRIPTION

       rtf_create_chebychev()  creates	a IIR chebychev filter processing nchann channels of data type specified by proctype with fc as normalized
       cutoff frequency, whose the Z-transform has num_pole poles and whose the impulse response has a ripple of r This latter is expressed as the
       ratio  between  the  overshoot  (difference  between  the max value of the response to a unit step and the unit length) and the unit length
       (ratio not expressed in decibels).

       rtf_create_butterworth() is the same as rtf_create_chebychev() but creates a butterworth filter (which a special case of a chebychev filter
       with a ripple of 0).

       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).

       If highpass is 0, it specifies the filter should be a lowpass. If highpass is non-zero, the should be a highpass.

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_CHEBYCHEV(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)

Linux and UNIX Man Pages

rtf_create_chebychev(3) [debian man page]

Check Out this Related Man Page