Tiny tool to change normal maps format?

Working with other tools, it’s common that my normal maps ends up getting the wrong format. That means I have to change them from directX to OpenGL or the opposite.
However opening a software just to convert them can be quite annoying. Is there a tiny software that only inverts normal maps and is very quick to start etc? I’m talking about changing the file itself, not only changing it in Blender.
Thanks :slight_smile:

And what about the usual node setup :

separate XYZ → x, (1-y), z → combine XYZ

Just make yourself a node group and reuse it “NormalConvert”

thanks for the answer, but I need a way to change the file itself quickly, not to change the normal map once it’s in Blender. For example, when combining normal maps made in different softwares so they all have the same Y direction.

Well… of course you could use any image processing /manipulation tool to invert the green channel… for example with Imagemagick… :

convert input -channel green -negate +channel output

( which may be the tiniest ??)

and also some normal map apps do have a convert or switch (green)/ invert (height) button… like jsut to name some examples:


Or maybe this (windows only?):


that was exactly what i was looking for, thank you <3