I made it as a standalone filter, you load it in your software (I usually use Substance Player) then input your un-normalized texture, set the parameters you want (output resolution, bit depth, and file format) and save the normalized file.
Why do we have to "normalize" our normal maps? Here's an example that hopefully helps illustrate it! Notice how the lighting is messed up in the edited normal map. You can't see the windows anymore on the dome and donut, and even the flat background is reflecting the wrong colors. This came up in my last post; I shared…