Well, probably not issue per se, more like "I found this bit of code" ...
https://github.com/ilia3101/LibMLV/commits/master
as far as I understand this is MLV (RAW video camera format from Magic Lantern developers) reading/writing library, so in theory one can write single file instead of many DNGs ...
https://www.magiclantern.fm/forum/index.php?topic=24386.50
"Topic: The MLV format "
As far as I understand ffmpeg can read this format, at least older version of it ...
you need commit before rewrite, where correct Makefile for library exist, and I also added " -lz" to main compiler line , where -lgomp lives, so gcc was sayng:
gcc raw2mlv.o libraw_r.a ../../lib/libmlv.a -o raw2mlv -lm -lgomp -lstdc++ -lz
not tested with any actual raw file yet ...