LABWINDOWS/CVI 数字滤波器函数Digital Filtering Use digital filtering to remove unwanted parts of a digital signal such as noise. LabWindows/CVI provides both finite impulse response (FIR) and infinite impulse response (IIR) filters.The LabWindows/CVI Advanced Analysis Library includes the following digital filtering functions:FunctionDescriptionAllocIIRFilterPtrAllocates and initializes the filter information structure, which is used with the IIR cascade filter coefficient design calls.Bessel_CascadeCoefGenerates the set of cascade form filter coefficients to implement an IIR filter as specified by the Bessel filter model.Bessel_CoefGenerates the set of filter coefficients to implement an IIR filter as specified by the Bessel filter model.Bw_BPFFilters the input array using a Butterworth bandpass digital filter.Bw_BSFFilters the input array using a Butterworth bandstop digital filter.Bw_CascadeCoefGenerates the set of cascade form filter coefficients to implement an IIR filter as specified by the Butterworth filter model.Bw_CoefGenerates the set of filter coefficients to implement an IIR filter as specified by the Butterworth filter model.Bw_HPFFilters the input array using a Butterworth highpass digital filter.Bw_LPFFilters the input array using a Butterworth lowpass digital filter.CascadeToDirectCoefConverts from cascade IIR coefficients to direct-form IIR coefficients.Ch_BPFFilters the input array using a Chebyshev bandpass digital filter.Ch_BSFFilters the input array using a Chebyshev bandstop digital filter.Ch_CascadeCoefGenerates the set of cascade form filter coefficients to implement an IIR filter as specified by the Chebyshev filter model.Ch_CoefGenerates the set of filter coefficients to implement an IIR filter as specified by the Chebyshev filter model.Ch_HPFFilters the input array using a Chebyshev highpass digital filter.Ch_LPFFilters the input array using a Chebyshev lowpass digital filter.Elp_BPFFilters the input array using an elliptic bandpass digital filter.Elp_BSFFilters the input array using an elliptic bandstop digital filter.Elp_CascadeCoefGenerates the set of cascade form filter coefficients to implement an IIR filter as specified by the elliptic (or Cauer) filter model.Elp_CoefGenerates the set of filter coefficients to implement an IIR filter as specified by the elliptic (or Cauer) filter model.Elp_HPFFilters the input array using an elliptic highpass digital filter.Elp_LPFFilters the input array using an elliptic lowpass digital filter.Equi_RippleDesigns a multiband FIR linear phase filter, a differentiator, or a Hilbert Transform using the Parks-McClellan algorithm.EquiRpl_BPFDesigns an optimal bandpass FIR linear phase filter using the Parks-McClellan algorithm.EquiRpl_BSFDesigns a bandstop FIR linear phase filter using the Parks-McClellan algorithm.EquiRpl_HPFDesigns an optimal highpass FIR linear phase filter using the Parks-McClellan algorithm.EquiRpl_LPFDesigns an optimal lowpass FIR linear phase filter using the Parks-McClellan algorithm.FIR_CoefGenerates a set of FIR filter coefficients based on the window design method.FreeIIRFilterPtrFrees the IIR cascade filter structure and all internal arrays.IIRCascadeFilteringFilters the input sequence using the specified cascade IIR filter.IIRFilteringFilters the input sequence using the specified IIR filter.InvCh_BPFFilters the input array using an inverse Chebyshev bandpass digital filter.InvCh_BSFFilters the input array using an inverse Chebyshev bandstop digital filter.InvCh_CascadeCoefGenerates the set of cascade form filter coefficients to implement an IIR filter as specified by the inverse Chebyshev filter model.InvCh_CoefGenerates the set of filter coefficients to implement an IIR filter as specified by the inverse Chebyshev filter model.InvCh_HPFFilters the input array using an inverse Chebyshev highpass digital filter.InvCh_LPFFilters the input array using an inverse Chebyshev lowpass digital filter.Ksr_BPFDesigns a digital bandpass FIR linear phase filter using a Kaiser window.Ksr_BSFDesigns a digital bandstop FIR linear phase filter using a Kaiser window.Ksr_HPFDesigns a digital highpass FIR linear phase filter using a Kaiser window.Ksr_LPFDesigns a digital lowpass FIR linear phase filter using a Kaiser window.ResetIIRFilterResets the internal filter state information to zero before the next cascade IIR filtering operation.WindFIR_FilterGenerates windowed FIR filter coefficients.