support SSIF files
Hey.
I've been making backups of some of my BluRays (using bluraybackup) and whenever I try to do so for 3D BluRays I get many errors about SSIF files not being supported: https://code.videolan.org/videolan/libbluray/-/blob/bb5bc108ec695889855f06df338958004ff289ef/src/libbluray/disc/disc.c#L607-608
Not sure how complicated it would be, but does it seem feasible to add support for that?
I'm not an expert, so TBH, I don't actually know what they're for. The only thing I could find out is, that they're not actually pristine content but can be re-generated from the M2TS files.
So very naively thought, once the mapping from SSIF to M2TS was known (maybe that is the difficult part?), shouldn't it be possible to use the very same mapping on the decrypted M2TS?
Maybe it would also make sense if libbluray would instead create&store the .ssif.smap
to save space.
Of course it would then also need to support these when reading (e.g. when someone wants to play back a 3D BluRay).
Thanks, Philippe