[PD] dc offset

[Alexandre Porres]

> Is it really DC offset when the value goes from 0 to 1 instead of -1 to 1?

just to be clear and straightforward.

when the midpoint is not zero, there is a DC Offset, which means you
introduce energy in the spectrum at 0Hz, so the maximum positive value must
be equal to the absolute negative value (-0.5 to 05 ,  -0.25 to 0.25, etc).
In the case the way phasor comes out of the box, midpoint is 0.5, and not
zero...

cheers
alex


On Mon, Mar 30, 2009 at 3:02 PM, Derek Holzer <derek at umatic.nl> wrote:

> Is it really DC offset when the value goes from 0 to 1 instead of -1 to 1?
> I mean, that's the way [phasor~] comes right out of the box.
>
> D.
>
> Alexandre Porres wrote:
>
>>
>> I tried again, and now it works much better than before... so I guess
>> there was something wrong before.
>>
>> Well Claude, it seems it almost works as the [triangle~] object.
>>
>> Do you guys know about this one? It comes in some external library.
>>
>> Were you who did it anyway Claude? :)
>>
>> [triangle~] works in a similar fashion, it goes smoothly from inverse
>> sawtooth to triangle and the sawtooth depending on the parameter (from 0 to
>> 1).
>>
>> The thing is that Triangle corrects the DC Offset, which could easily be
>> done in the expr. But now I may start to sound like an obssessed DC Offset
>> maniac.
>>
>> Cheers
>> Alex
>>
>>
>> On Mon, Mar 30, 2009 at 1:25 PM, Claude Heiland-Allen <
>> claudiusmaximus at goto10.org <mailto:claudiusmaximus at goto10.org>> wrote:
>>
>>    Alexandre Porres wrote:
>>
>>        On Mon, Mar 30, 2009 at 12:02 PM, Claude Heiland-Allen <
>>        claudiusmaximus at goto10.org <mailto:claudiusmaximus at goto10.org>>
>>        wrote:
>>
>>
>>            [phasor~]                               [r~ shape]
>>            [expr~ if($v1<$v2,$v1/$v2,(1-$v1)/(1-$v2))]
>>
>>
>>        I tried that, but it didnt actually worked, I just get actual
>>        sawtooths, and
>>        no real triangles.
>>
>>
>>    Sorry for the shortness/lack of explanation, 0<shape<1, where 1 for
>>    phasor, 0.5 for triangle, 0 for backwards phasor.
>>
>>    considering shape as a constant, obviously you get weird results if
>>    you modulate it, but that's half the fun:
>>
>>    0.0   <= input <= shape  ~>  0.0 <= output <= 1.0  (rising ramp)
>>    shape <= input <= 1.0    ~>  1.0 >= output >= 0.0  (falling ramp)
>>
>>    Hope this helps,
>>
>>
>>
>>    Claude
>>    --    http://claudiusmaximus.goto10.org
>>
>>
>>
>>
>> --
>> Alexandre Torres Porres
>> cel. (11)8179-6226
>> Website: http://porres.googlepages.com/home
>> http://www.myspace.com/alexandretorresporres
>>
>>
> --
> ::: derek holzer ::: http://blog.myspace.com/macumbista :::
> http://www.vimeo.com/macumbista :::
> ---Oblique Strategy # 35:
> "Consider transitions"
>



-- 
Alexandre Torres Porres
cel. (11)8179-6226
Website: http://porres.googlepages.com/home
http://www.myspace.com/alexandretorresporres
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