search for: mkfilter

...; then \ /sbin/update-modules ; \ fi /sbin/depmod -a [ -f /etc/zaptel.conf ] || install -m 644 zaptel.conf.sample /etc/zaptel.conf ivr2:/usr/src/zaptel # cd .. ivr2:/usr/src # cd zapata ivr2:/usr/src/zapata # make clean; make install rm -f *.o rm -f libzap.a mkcoef p_tmp_ libzap.so* make -C mkfilter clean make[1]: Entering directory `/usr/src/zapata/mkfilter' rm -f mkfilter.o mkshape.o mkaverage.o gencode.o genplot.o complex.o readdata.o rm -f mkfilter mkshape mkaverage gencode genplot make[1]: Leaving directory `/usr/src/zapata/mkfilter' gcc -Wall -Wstrict-prototypes -march=pentium -O...

...es of data from an electroencephalogram (EEG). I wish to filter the data to get rid of 50Hz mains 'hum'. I have 'designed' a combination bandpass and notch filter using a web- site. The site returns the filter in "ANSI C" source code. It is:- /* Digital filter designed by mkfilter/mkshape/gencode A.J. Fisher Command line: /www/usr/fisher/helpers/mkfilter -Bu -Bp -o 5 -a 1.0000000000e-02 1.0000000000e-01 -Z 2.0000000000e-01 -l */ #define NZEROS 12 #define NPOLES 12 #define GAIN 1.548068051e+03 static float xv[NZEROS+1], yv[NPOLES+1]; static void filterloop() { for...

Dr. Williams, I ran across your inquiry on one of the R-help mailing lists regarding digital filter design and implementation. I found no response to your email in the archives and was wondering if you were able to find anything. Thanks, Israel -- Israel Christie, Ph.D. Email: ichristie at gmail.com Phone: 865.766.0214 Mobile: 865.406.4615

...then drop every second (or 2 out of 3 for 48000->16000) sample. The result being, 16000Hz sampled audio. If you omit the filter the result will contain artifacts. At the other end for playback you can convert it back to 48000 (or whatever) by You can use http://www-users.cs.york.ac.uk/~fisher/mkfilter/trad.html to generate such a filter, choose Butterworth + lowpass, filter order 10, put your sample rate in, and corner frequency 1 8000Hz. Failing that, you could use http://www.mega-nerd.com/SRC/ to do the resampling for you if you're prepared to GPL your code or cough up for the license. Th...

...gt; 48000->16000) sample. The result being, 16000Hz sampled > audio. If you omit the filter the result will contain artifacts. > > At the other end for playback you can convert it back to > 48000 (or whatever) by > > You can use > http://www-users.cs.york.ac.uk/~fisher/mkfilter/trad.html to > generate such a filter, choose Butterworth + lowpass, filter > order 10, put your sample rate in, and corner frequency 1 8000Hz. > > Failing that, you could use http://www.mega-nerd.com/SRC/ to > do the resampling for you if you're prepared to GPL your code &g...