HSVLfromROI.

Select a region in the Viewer. Press a shortcut. Keep the average colour values in your node graph.

HSVLfromROI - quick sampling and optional Constant creation. The steps are also described below.

Get the tool

Download on Nukepedia Source code on GitHub ↗

Installation details are available with the tool. Example menu and more Python tools on GitHub ↗

How it works

Draw a colour-sampling region in Nuke's active Viewer.
Press Ctrl + Shift + Enter to create a StickyNote with the average RGB and HSVL values.
Use Ctrl + Shift + Alt + Enter to add a label or create a Constant from the sampled colour.

Both commands are also available under HSVL Sampler in the Viewer menu.

About the values

The tool samples the image connected to the Viewer, before the Viewer display transform. HSV is calculated from the averaged RGB sample; L uses fixed Rec.709 luminance weights. It is not a display colour picker or a colour-space conversion, so L needs care with working spaces such as ACEScg. HDR values can exceed 1.

Questions or feedback? Get in touch.