[mythtv] [PATCH] better avi seek support

[Mark Spieth]

> I'm _fairly_ sure that av_seek_frame() should do the right thing for an
avi,
> even with our replaced i/o functions.  We just need a frame number, that
way,
> and it'll use avformat's internal index.

I have no doubt that that would work.
however, the file io is not being performed by the same engine, and the file
handle(s) are not consistent (I think).
seeking with one handle and reading in the other is not a good thing.
this is what complicates things.
mark