Needed to modify vertex colours like in photoshop, This tool copies vertex colours to a 1x1x1 point cloud, HSV > XYZ.
You can modify the vert locations and copy the colours back to the mesh when your done. Like Hue/Saturation/Brightness in the Gimp.
Instructions on my page…
Later I may add YUV, RGB and other colour models. at the moment HSV is most usefull.
Cambo:
I want to thank you a lot for your work with this python scripts
It has become my favorite collection of “truly working” scripts
I’ll try this new vertex colors script and let you know my opinion
For the moment i only want to ask you about “another” script i found in your page -that is- advanced array… i just don’t know how to put it to work, maybe i’m doing something wrong.
Coul you explain a little more in how to use it
I know, I know, maybe this is not the best place to ask about an older script but … 
be patient
WOW! Freakin cool!
No really… nice script. So, how does this concept work? does every point in the cloud stand for a vertex of the original mesh and it’s colour?
Or does each point display a certain color when used, and you can move around that certain colour?
Just testing… yes, that must be it.
so if you moved only one point, one certain HSV color in the original mesh would change?
(EDIT: must have missed the text on the image… it’s written there already. :-? )
Anyway, i’m having a lot of fun using proportional editing on the pointcloud.
But i guess this is more for scaling or moving and by that changing contrast or brightness…certainly usefull!