[linux-audio-user] Digital audio files for hardware verification

[Mark Knecht]

On 10/25/05, Paul Winkler <pw_lists at slinkp.com> wrote:
> Awk is powerful and concise, but it's not my friend - I can never remember how
> the heck it works ;-)
>
> I'd probably do like Paul D. suggests and use existing tools - e.g.
> find something
> to generate an appropriate soundfile, then feed it through sox.
> But just for fun, here's something silly I just whipped up:
>
> $ ./sine_hex.py
> Usage: ./sine_hex.py frequency [sampling rate] [bits]
> Print one cycle of a sine wave of approximately the
> given frequency.
> Values given in hex with *bits* precision at *sampling rate*.
> Default sampling rate is 44100. Default bits is 16.
>
> pwinkler at Winkler-P-LT2K ~
> $ ./sine_hex.py 24000 48000
> 0000
> ffff
>
> pwinkler at Winkler-P-LT2K ~
> $ ./sine_hex.py 3000 48000
> 0000
> 31f1
> 61f7
> 8e39
> b504
> d4da
> ec82
> fb14
> ffff
> fb14
> ec82
> d4da
> b504
> 8e39
> 61f7
> 31f1
>
> And here's the source. Most of it is argument handling :-)
> http://www.slinkp.com/~paul/sine_hex.py
>

Intereing. Another country heard from.

One question that comes to mind, as I play with these solutions, is
deciding how to evaluate the outputs. For instance I was fiddling with
generating a sawtooth from Marcus' s method. I could do the same with
this, but how do I know each of them is really implementing what I'm
interested in?

What tools do people use for FFT analysis on files like this?

Cheers,
Mark