During a project I build this tool I would like to share.

With the Octane Material Builder ( download link below ) you can automatically build Octane Materials ( textures ) in Houdini. Add all the nodes like Color, Spec, Displacement, etc.. according to the flags set in the HDA for each texture. So no need to set those up manually. Save time by setting the file path to the texture map once in the Global Texture Dir and this directory will be added to each image node for all the textures.
Set ( update ) and Clear random colors for both OpenGL and Octane at any time.

You can download the OMB in the next link:
https://www.orbolt.com/asset/Carlo_Jongen::octane_material_builder::1.04

OMB Teaser on YouTube:
https://youtu.be/cPeiDGBLDbk [youtu.be]

OMB Full explanation video:
https://youtu.be/-hW7gvOPt3M [youtu.be]

Enjoy...