[PD] gem alpha channel q

[marius schebella]

pix_gain 1 1 1 -1 should do this.
although I think there is a bug in some gem versions. and maybe you
have to use something like 1 1 0.9999 -1 to get it to work.
marius.

2009/10/14 rene beekman <r at raakvlak.net>:
> that inverts the entire image, not just the alpha channel...
>
>
> On Oct 14, 2009, at 05:35, Jose Luis Santorcuato wrote:
>
>> [pix_invert]...i think...
>>
>> Cheers
>>
>> Chile
>>
>> 2009/10/11 rene beekman <r at raakvlak.net>
>>
>> how does one invert an alpha channel in gem ?
>> i've created an alpha channel from the rgb channels, but need the channel
>> to be inverted. somehow i can't seem to find a way to do this...
>>
>> hope it is just sleep deprivation and i'm simply overlooking the
>> obvious... :)
>>
>> thanks in advance,
>>
>> rene
>>
>>
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>>
>
>
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