Whenever I try to query a pixel colour value using either the “picni” or “pic” as an expression in a colour COP and then try to display the result arrived at using the expression, houdini hangs. Is there a better way to retrieve a pixel's colour value?
You can use a vop sop with the Color Map vop, it is much faster than using pic or picni in a point sop for example. If you are pulling the image from COP instead of a file you can use the op syntax.
I have attached a very quick hip to attempt to demonstrate