CNM video files

[pitito]

I need help with this type of format of which I have two variants, one is the PC version and the other is the Dreamcast version.
My idea is to demux both versions to be able to mux the Dreamcast version with the audio of the PC version, since this audio is in my language.

I've found some information on this type of fmv, which seems to use the cin and cin2 codec on github, but I haven't been able to figure out how to create any tools.
I have also tried with ffmpeg, but it doesn't seem to support this format

Info codec

https://github.com/Templier/scummvm/tree/ring/engines/ring/graphics/movies

files