On Sat, Jan 15, 2011 at 10:50 AM, Rudolf Sykora <rudolf.syk...@gmail.com> wrote: >> Read N PCM samples from the sound card, this is just a read from the >> audio in file, easy part. >> The samples you can read from >> http://plan9.bell-labs.com/magic/man2html/3/audio >> audio(3) or a similar interfaces provided by usb/audio usb(4). > > Ok. To start with, audio(3) seems to support soundblaster-16-compatibles. > What about others? I guess mine could be AC'97 on one of my notebooks > (there fortunately seems to be some support for this one elsewhere, > too), while god knows what on another. Connected to this: > How do I find from within plan 9 what soundcard/hardware I have? > >> This last part, I would use draw >> http://plan9.bell-labs.com/magic/man2html/2/draw >> draw(2). You can use control >> http://plan9.bell-labs.com/magic/man2html/2/control control(2) >> to add sliders but for what you are doing just drawing rectangles and >> lines should be fine. > > Ok. I ask because some widget sets already have an analog-like gauge > I'd like to use, e.g. Tk::gauge. (What'd be the situation in Inferno? > They have some Tk, don't they?) > > Thanks > Ruda > >
If you're tuning a wind instrument, you could just print out the frequency of middle C and then display the calculated frequency coming into the microphone below it. For a guitar tuner, just print out more frequencies (EADGBE)... this is the lazy man's way to do it, but it would be a way to test it at first, at least. If I wanted to make it fancy and graphical, I'd have a horizontal line, bisected in the center by a vertical line representing the target frequency, then draw another moving vertical line to represent the current frequency. John
