This tool is for older NVIDIA blob versions. These had netlist archives embedded in them with gzip headers, and the video firmware was raw data in the object file.
The output of the tool is the video firmware, and optionally, the extracted netlists classified by GPU (to potentially use in place of the nouveau-made firmware). This classification is only done for very specific versions.
This is an explorational tool (written in Go!) to search for compressed blobs inside of the blob object file. It uses relocation data to locate potentially interesting bits of the rodata to search through. The outputs are netlist archives, as well as "whole" files. These tend to be falcon programs, but some are just data files.