All of these files in reserve is essentially a sqlite database (or chunks of one database, I do not remember). A year ago I managed without special. programs (only a handy tool for sqlite) to retrieve the piece of information. Manually doing it is not that difficult.
iphonebackupextractor.com and such programs make the process more effective (I later realized).
Some files, like, it's just a renamed jpg images (that are of a great size)