Digital filter

About: Digital filter is a research topic. Over the lifetime, 21376 publications have been published within this topic receiving 322402 citations.

Digital Filter Design

Abstract: Introduction to Digital Filters Properties of Finite Impulse-Response Filters Design of Linear-Phase Finite Filters Minimum Phase and Complex Approximation Implementation of Finite Impulse-Response Filters Properties of Infinite Impulse-Response Filters Design of Infinite Impulse-Response Filters Implementation of Infinite-Response Filters Comparison of Filtering Alternatives Appendix Index

Adaptive deblocking filter

Abstract: This paper describes the adaptive deblocking filter used in the H.264/MPEG-4 AVC video coding standard. The filter performs simple operations to detect and analyze artifacts on coded block boundaries and attenuates those by applying a selected filter.

A continuously variable digital delay element

Abstract: The author describes an FIR (finite-impulse-response) filter which synthesizes a controllable delay. By changing the delay the filter has the ability to interpolate between samples in the data stream of a band-limited signal. Because high sampling rates are not required, the filter is especially suited for implementation in a digital signal processor (DSP), and has been implemented in a real-time DSP. The interpolator can be used as a practical way to reconstruct an original band limited signal from samples taken at the Nyquist rate. The variable delay filter can also be used as a more general computational element. Performance results are presented. >

Chebyshev Approximation for Nonrecursive Digital Filters with Linear Phase

Abstract: An efficient procedure for the design of finite-length impulse response filters with linear phase is presented. The algorithm obtains the optimum Chebyshev approximation on separate intervals corresponding to passbands and/or stopbands, and is capable of designing very long filters. This approach allows the exact specification of arbitrary band-edge frequencies as opposed to previous algorithms which could not directly control pass- and stopband locations and could only obtain (N - 1)/2 different band-edge locations for a length N low-pass filter, for fixed \delta_{1} and \delta_{2} . As an aid in practical application of the algorithm, several graphs are included to show relations among the parameters of filter length, transition width, band-edge frequencies, passband ripple, and stopband attenuation.

Frequency Filter for Time Integrations

Abstract: A simple filter for controlling high-frequency computational and physical modes arising in time integrations is proposed. A linear analysis of the filter with leapfrog, implicit, and semi-implicit, differences is made. The filter very quickly removes the computational mode and is also very useful in damping high-frequency physical waves. The stability of the leapfrog scheme is adversely affected when a large filter parameter is used, but the analysis shows that the use of centered differences with frequency filter is still more advantageous than the use of the Euler-backward method. An example of the use of the filter in an actual forecast with the meteorological equations is shown.