• requires:

  • sox for input preprocessing

  • convolve

  • hist

  • fftw-dev for libfftw, librfftw

  • glib-2.0

  • gtk+-2.0

  • the makefile currently uses pkg-config to determine the library paths for the libraries. $ apt-get install pkg-path

• input and output

  • input must be 8bit signed single channel audio
  • for convolve the sampling rate does not matter
  • hist calculates absolute frequency with sampling rate fixed to 22050 but doesnt care if its not the actual sampling rate
  • output is exaclty the same format

• usage of hist

  $ hist windowtitle windowtitle will be used as title for the histogram

  hist reads a block from stdin, performs a fft on it and displays the data in a logarithmic display (x,y is logarithmic)

• usage of convolve

  $ convolve kernelfile

  convolve first reads the kernel file. the kernel file must have a structure like (BNF):

  file = { float }.

  the number of numbers in the file must match the current kernel size which is compiled into the convolve.

  example:

  0.0 -2.0 0.0 2.0 0.0

  which would be something like a highpass filter

  then the convolve application reads samples from the input and convolves it with the configured kernel.

  the convolved data is written to stdout.

• synth

  simple synth creating tones on a mathematical model of ck's

• synth2

  simple synth reading ck's from a file

• vocoder

  removes frequencies from input

• song

  ./song | ./play.sh

  plays the song in "song.txt" using something like in "synth"

• midi

  ./midi file.mid | ./play.sh

• typical usage:

sox mm.wav -1 -r 22050 -c 1 -t raw - | ./hist "orig" | ./convolve hp.kernel | ./hist "filt" | play -1 -r 22050 -c 1 -t raw -s -

mpg123 test.mp3 --wav mm.wav sox mm.wav -1 -r 22050 -c 1 -t raw mm.raw cat mm.raw | ./hist "orig" > /dev/null cat mm.raw | ./convolve hp.kernel > hp.raw cat hp.raw | ./hist "hp" | play -1 -r 22050 -c 1 -t raw -s -