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Hi Joan,
Thanks for sharing those!
On 02/24/2012 11:12 AM, Joan Quintana wrote:

quoted text
> Related with this topic, I would like to contribute with 3 pieces of code made with an educational point of view (though I don't teach audio processing and I don't consider an expert myself). These examples use libsndfile library, that is important if the source or the destination of your audio data is a wav file.

>

> a) jcapture:

> *http://wiki.joanillo.org/images/0/07/Jcapture-1.0.0.tar.gz

> reads the data coming from the microphone, and saves a wav file. Shows a textual signal meter in the console. (I know the existance of jack-capture. I didn't look at jack-capture code, sure that has better performance and lots of options, I just wanted the minimal code)

The linked tar-ball includes jcapture-0.0.1.cpp that does not save any

.wav file.
Calling printf() in the jack-callback function is not realtime safe;

[but it's perfectly valid for debugging/development purposes and] I

guess you simply mixed up the files.
FWIW

https://github.com/jackaudio/example-clients/blob/master/capture_client....

is very close to the minimal code required to do disk I/O. It does not

include a meter, but supports multiple-channel.
> b) jplay-sndfile-simple:

quoted text
> *http://wiki.joanillo.org/images/1/1e/Jplay-sndfile-simple-1.0.0.tar.gz

> It's just a playback wav file. In the callback function there are two possibilities: copying blocks of memory; or copying sample by sample, and this permits a little signal processing (in this simple case just divide the signal by 2).

> I borrowed code from sndfile-jackplay.c (sndfile-tools-1.03, Erik de Castro Lopo & Jonatan Liljedahl), where is interesting the thread implementation  (playing while reading the file) that I didn't implemented.

neat. There's some cruft in it (unused variables, binary (&) vs boolean

(&&) AND in line 89) - compile with `-Wall` option: g++ will tell you.
Otherwise it'd make a nice addition to

https://github.com/harryhaaren/Linux-Audio-Programming-Documentation
> c) jplay-sndfile:

quoted text
> *http://wiki.joanillo.org/images/e/e6/Jplay-sndfile-1.0.0.tar.gz

> This is more interesting and not simple like the previous. A part of playing back the file, it permits frequency shifting and frequency sweeping in a range between .5 and 2.

see previous email (reply to Harry).
> Hope this helps to somebody,

quoted text
> Joan Quintana

>

> 

best,

robin

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