ao@lne.kth.se (Anders Ohlsson (Royal Institute of Technology, Stockholm, Sweden)) (09/05/90)
Can anyone help me with an algorithm for filtering speech files that are sampled at 8 kHz. I am going to downsample them to 6 kHz, and need to have a 3rd order LP-filter at 2.8 kHz. I'd greatly appreciate if someone could point me to a program that does this. If it's available, I'd like a general program for LP-filters, HP-filters, bandpass and bandstop-filters (nth-order). Any algorithm or program for calculating the filter parameters would appreciated. Thanks in advance, Anders Ohlsson -------------------------------------------------------------------- | In real life: Anders Ohlsson E-mail: ao@lne.kth.se | | ao@infovox.se | | | | "Complex problems have simple, easy-to-understand wrong answers" | --------------------------------------------------------------------
north@manta.NOSC.MIL (Mark H. North) (09/06/90)
In article <0093C415.AB8D7C00@lne.kth.se> ao@lne.kth.se (Anders Ohlsson (Royal Institute of Technology, Stockholm, Sweden)) writes: > > Can anyone help me with an algorithm for filtering speech > Any algorithm or program for calculating the filter > parameters would appreciated. > An excellent book in this regard is Stearns, S.D., "Digital Signal Analysis", Hayden Book C. 1975. Unfortunately it is out of print but your library may have it. Mark
grosen@amadeus.ucsb.edu (Mark D. Grosen) (09/06/90)
In article <1199@manta.NOSC.MIL> north@manta.nosc.mil.UUCP (Mark H. North) writes: >In article <0093C415.AB8D7C00@lne.kth.se> ao@lne.kth.se (Anders Ohlsson (Royal Institute of Technology, Stockholm, Sweden)) writes: >> >> Can anyone help me with an algorithm for filtering speech >> Any algorithm or program for calculating the filter >> parameters would appreciated. >> > >An excellent book in this regard is Stearns, S.D., "Digital Signal Analysis", Hayden Book C. 1975. Unfortunately it is out of print but your library may have >it. > >Mark There is a second edition out of this book: "Digital Signal Analysis" S. D. Stearns and D. R. Hush Prentice Hall 1990 ISBN 0-13-213117-X It comes with a DOS floppy with Fortran source code and includes some simple design routines. You might also check out "Digital Filters" by Tom Parks (sorry, I don't have the book here). This is a comprehensive look at designing filters and includes Fortran code (but no disk). There are several commercial SW packages available, but they are rather expensive. Mark Mark D. Grosen ARPA: grosen@amadeus.ucsb.edu Signal Processing Lab / Communications Research Lab ECE Dept. University of California Santa Barbara, CA 93106