PtFilter - Interactive Digital Filter Design Tool


PtFilter is an interactive animated digital filter design tool that can be used both in engineering design and education.

PtFilter is no longer under development, and the source code is not available for download. The applet may or may not work.

  • ILP 1998 summary
  • Sample Screen shot
  • Applet version Currently, the applet only works for IIR filters with Butterworth approximation in Bilinear transform, but you can design highpass, lowpass, bandpass, bandstop filters.