No, it's parts of Dreamcast development kit. IMO it's a mess and it's part of the reason it failed. So the lower level libraries is called kamui(there's kamui1 and 2), at the higher level is ninja( ninja1 and 2) and Naomilib(developed by am2 and used a lot in Naomi and it's ports). There's a library lower than kamui but it's not worth mentioning.
Naomilib is used by the likes of 18 wheeler, f355 challenge, virtual fighter 3, fighting vipers 2 AND yes dead or alive 2 is built on it. ( This why it's always a topic how the heck is doa2 is miles better than the rest) seems to perform better than ninja.
Ninja is library meant to make dc dev easy for JAPANESE devs( western devs weren't allowed to use it and could only use kamui). Handles graphics, sound, movies, controls , does lighting for you, has model formats( exporter can activate things like transparency and env map without code) and animation and some very basic help in collision. Ninja 1 performance was pretty bad with specular highlights, not so good render to texture performance, polygon performance isn't great. Used A LOT of Japanese in both third party and first party(Sega).
Ninja2 is an evolution of the above but performance greatly improved ( according to SC2 guy it's to 2x to 3x faster). It added specular control, bump mapping , updated the model format and removed outdated features while adding new things to graphic support( improved rtt) . NO game uses this except for a 2d dating sim on the Dreamcast. Posted screen shot below of performance difference for nj1 and nj2 via sc2 models, nj1 struggles to keep 30 fps and constantly falls to 20 fps with 1 light source, nj2 version same exact scene but with 3 light sources and runs 30 fps no dips even when zoomed out. Same guy also tested render to texture feature and it's a lot faster basically felt radial blur is now freeish.( Since you don't have the render stuff off screen , it could just copy the finished frame and used as a texture doesn't increase scene complexity!)
Sc2 models , nj1 ( 1 light)
Sc2 scene , ninja 2( 3 lights)