Install libnvtt-bin by entering the following commands in the terminal:
sudo apt update sudo apt install libnvtt-bin
NVIDIA Texture Tools (Binaries)
NVIDIA Texture Tools is a collection of image processing and texture manipulation tools, designed to be integrated in game tools and asset conditioning pipelines. The primary features of the library are mipmap and normal map generation, format conversion and DXT compression. . This package contains the nvidia texture tools.