[GEM-dev] [ pd-gem-Bugs-2779564 ] pix_chroma_key uses RGB values from 0-255, not 0-1

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Bugs item #2779564, was opened at 2009-04-23 16:39
Message generated for change (Comment added) made by zmoelnig
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Category: Pixes (pix_ objects)
Group: None
Status: Open
Resolution: Fixed
Priority: 5
Private: No
Submitted By: Hans-Christoph Steiner (eighthave)
Assigned to: Nobody/Anonymous (nobody)
Summary: pix_chroma_key uses RGB values from 0-255, not 0-1

Initial Comment:
For whatever reason, [pix_chroma_key] uses RGB values between 0 and 255 rather than 0 and 1 like the rest of Gem.  

http://lists.puredata.info/pipermail/gem-dev/2009-04/003952.html

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>Comment By: IOhannes m zmlnig (zmoelnig)
Date: 2009-06-02 16:07

Message:
then it will be interpreted as a normalized value. this shouldn't be a big
problem, as in practice a range of 1/256 is rather small and a value of
1/256 is rather dark.

note that _all_ 3 values have to be <= 1 in order to interpreted as
normalized values.

anyhow: Gem now spits out a warning when using non-normalized values

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Comment By: Nobody/Anonymous (nobody)
Date: 2009-06-02 15:55

Message:
And what happen if the value == 1 (between 0 - 1 and between 0 - 255) ?

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Comment By: Cyrille Henry (nusmuk)
Date: 2009-06-02 15:47

Message:
using 2 diferents ranges depending on the input value is very confusing.
i agree with HCS : a warning should be send if a value > 1 is send so the
user should know that it must divide by 255 the input.


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Comment By: Hans-Christoph Steiner (eighthave)
Date: 2009-06-02 15:36

Message:
>From what I understand, this will now respond to both 0-1 and 0-255.  I
think this could lead to some very confusing bugs/behavior.  How about just
issuing a warning that the data range changed from 0-255 to 0-1?

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Comment By: IOhannes m zmlnig (zmoelnig)
Date: 2009-06-02 10:41

Message:
should be fixed with revision 2828.
the behaviour is now: if all of the |values| are <=1.0, then we assume
they are normalized, else we switch to legacy mode.


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