[felice2011]

mmm, the utility it is based on the structure arc.group, used as reading for the selection of the files and compression masked in the different methods, but logically a file with the extension *.CAS, it can be structured with streams or not, for be directed automatically the file in a "deflate" or "void" mask should be first examined, scanned with one of your tools (DS4 LZ4/DS4 zLIB), and then inserted.
I do not have the source code to scan and verify the structure of the files, the utily was created to exploit in the best way the masked methods, in order to avoid adding unnecessary masks to unnecessary files, but if a file extension (*.dat) it is not a video but other, is a whole other story.