CIS525 Project -- Digital Signal Processing with Java


This web site is written as a learning exercise in the use of Digital Signal Processing (DSP) tools to manipulate digital audio data.
</COMMENT> <B> Sorry, these examples require Java </B>
Things to look at or hear on this web site: Technical things behind the scenes:
  • Digital music is played from a .WAV file
  • The waveform is plotted on a frequency spectrum using the Fourier Transform
  • The music is filtered digitally, and then replayed.
  • The use of Java applets with sound applications is an emerging technology. This software is not yet supported by most browsers without the use of Plug-ins.
  • Other User Information...
  • The program is written for different music formats. (Multi Sampling Rates/ 8 or 16 bit words / Mono or Stereo)
  • The frequency plotting tools were developed with Really Slow Fourier Transforms, then replaced with much quicker tools.
  • Threads are used within the play sound routines.
  • The digital filtering is done with Finite Impulse Response (FIR) Ideal_Bandstop Filter. This filter is set to as a low pass filter set to 10% of maximum frequency. (Best for 44,100 byte/sec sampling)
  • Because this is developed as an applet, web security adds significant problems to software development.
  • Other Developer Information
Links: Author: Lee Corney (email me?)
Key Reference: "Digital Filter Designer's Handbook", by C. Britton Rorabaugh, c1997
This program was written for CIS525, University of Michigan, Dearborn. (Dec 00)