Virtual ROM file system (.vromfs.bin)
Virtual ROM file system (*.vromfs.bin) is a type of container file that holds a highly compressed structure of text, images, or video, used by the game engine on which War Thunder was built - the Dagor Engine. War Thunder typically stores these files in the game's root directory.
While most data is stored in binary formats, which are faster for computer programs to read and generally smaller than text formats, the latter offers the advantage of being human-readable and editable with a basic text editing programme instead of complex editing software. The format uses either zlib or Zstandard compression algorithms to significantly reduce the file size; for example, a 9.9 MB aces.vromfs.bin file will unpack to 100 MB of content.
Gaijin does not provide any official tooling for extracting the *.vromfs.bin files. Majority of the War Thunder *.blk files are stored within *.vromfs.bin, similarly a lot of tools within the Content Development Kit read the contents of the *.vromfs.bin.
