How do I get the colour of a pixel in an image?

apilkiw · April 8, 2009, 1:32pm

Hi All!

Is there an way to get the colour of a pixel at some (u,v) in a given image (some random TOP)?

I’ve come across the Render Pick CHOP, but for that to work i need to render the image in onto a rectangle in 3D. I was wondering if there is something simpler.

Thanks,

A

Achim · April 8, 2009, 1:50pm

Hey apilkiw,
the TOPto CHOP with crop parameter set to “pixel(U,V)” should do what you want

apilkiw · April 8, 2009, 1:58pm

Perfect !!!

Thank you !

A

malcolm · April 8, 2009, 4:02pm

As a side note, the speed of the TOP to CHOP node is tied directly to the resolution of the image it’s sampling, so if you want to speed it up, try using a Crop TOP to reduce the resolution before you use TOP to CHOP.

ben · April 8, 2009, 5:06pm

Those interested in and example of this can checkout the ColorMeter component in the Tools folder of the Palette. It uses this techinique to sample the color anywhere in the TouchDesigner interface.