[Fluxus] Noisy output from (gh)

[Chris Targett]

Nah, Using Ubuntu 9.10. The example script from (help "ga") shows a

Just to verify, when fed a plain sine-wave, the following script
should just show a single bar with a constant value, correct?

(define (anim)
    (for ([x (build-list 16 values)]) (with-state
        (translate (vector x 0 0))
        (scale (vector 1 (gh x) 1))
        (draw-cube)
    ))
)
(every-frame (anim))

One interesting thing to note, not sure if it's of any significance,
but when fed a 560hz sine-wave from Jaaa the above script will show
the value of (gh 8) go from zero to full and back to zero every 4
seconds whereas other frequencies will have a much higher rate.

Cheers for the help,
Chris Targett

On Thu, Dec 24, 2009 at 12:21 AM, evan.raskob [lists]
<lists at lowfrequency.org> wrote:
> I wonder if this is related to what we see using (ga) on OS X where half of
> the jack audio buffer is zeros?
>
> Are you on OS X?
>
>
> On Dec 23, 2009, at 10:21 AM, Glauber Alex Dias Prado wrote:
>
>> Chris Targett <xin at xlevus.net> writes:
>>
>>> Humm,
>>>
>>> Even after
>>> * Blitzing all of Jack's preferences
>>
>> try increasing not only jack's buffer size(period) but also nperiod (3
>> or higher)
>>>
>>> * Using a buffer size in Fluxus of 2048
>>
>> Buffer size of fluxus has to be the same as jack.
>>>
>>> * Using the 'dummy' JACK driver to bypass any dodgy audio devices
>>
>> dont use this, try alsa and make sure it is configured for your card.
>>
>> You can bypass jack with reading from a wav file directly as dave
>> mentioned, with:
>> (process "somemusic.wav")
>>
>>>
>>> I'm still getting the same result, everything is jumping around like
>>> crazy.
>>> It's as if Fluxus was getting a fed bunch of zeros and then a big
>>> surge of non-zeros to make up for it.
>>>
>>> Is there anything else I can try?
>>>
>>> Ta
>>> Chris Targett
>>>
>>>
>>>
>>> On Tue, Dec 22, 2009 at 2:04 AM, Dave Griffiths <dave at pawfal.org> wrote:
>>>>
>>>> On Mon, 2009-12-21 at 12:52 +0000, evan.raskob [lists] wrote:
>>>>>
>>>>> On Dec 21, 2009, at 12:57 AM, Glauber Alex Dias Prado wrote:
>>>>>>>>
>>>>>>>> I thought it was the music I was listening to and used Jaaa to
>>>>>>>> generate a pure sinewave but I still get the same result.
>>>>>>>>
>>>>>>>> Is this likely to be an issue with Fluxus, or
>>>>>>>> something/bad-configuration in Jack?
>>>>>>
>>>>>> isnt the gh code not dependendant on jack, only on the audio
>>>>>> sources?(audio file)
>>>>>
>>>>> This is true, but noisy audio in == noisy result, which can be due to
>>>>> jack adding glitches and noise (this certainly happens to me a lot).
>>>>
>>>> If you read from a wav file jack isn't involved.
>>>>
>>>> It's much more likely to be a problem with the fft implementation in
>>>> fluxus than anything to do with jack (which is specifically designed to
>>>> prevent clicks and glitches, and works pretty well in my experience).
>>>>
>>>> cheers,
>>>>
>>>> dave
>>>>
>>>>
>
> Evan Raskob
> ML Studio
> 4-8 Arcola Street
> London E8 2DJ
> United Kingdom
>
> http://mlstudio.co.uk
> http://pixelist.info
>
>