Rev Graphics Gurus

Scott Rossi scott at
Tue Oct 17 12:59:25 EDT 2006

Recently, John Vokey wrote:

> I have two general questions (which ultimately will evolve into many
> more).  I need to manipulate the contents of images in Rev in two ways:
> 1) I need to average, pixel by pixel, two images (of the same size)
> before display of that average.  So, the question is: how do I access
> the individual pixels of the two images?

The imageData property.  You should really see this page on Ken Ray's site
for a thorough explanation:

> 2) I need the end user to be able manipulate within Rev under user
> control the RGB of CMYK settings of an image (e.g., increase B, while
> decreasing R, and so on) much like the RGB and CMYK sliders in the OS
> X Colors palette, and then apply (on the fly) those new settings to a
> displayed image.

The first thing that comes to mind for me is that if your images are of any
significant dimension, ie several hundred pixels in width/height, then
modifying the imageData of the images is going to be a bit slow.  You might
want to first play around with using a graphic as an overlay above an image,
with the new ink settings in Rev 2.7, and possibly the blendLevel property
to adjust the amount of "adjustment" applied to an image.  In other words,
use the graphic as a filter of sorts that affects the view of the image

I don't have any experience with CMYK myself, but Monte Goulding has color
library that is supposed to be able to convert between lots of different


Scott Rossi
Creative Director
Tactile Media, Multimedia & Design
E: scott at

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