On Mon, Oct 21, 2013 at 5:46 PM, Carl Eugen Hoyos <[email protected]> wrote: > Robert Krüger <krueger@...> writes: > >> Since only P- and I-slices are parsed (I can see that >> in the debug output), I would indeed expect every >> I-frame (meaning any frame only consisting of one >> I-slice in the stream) to be a valid access point > > So you mean a P-frame after an I-frame is not allowed to > reference an earlier I-frame? > I don't think this is correct.
You are probably correct here. I have to check the spec. Would be a very weird stream, though. Have you seen such a beast in the wild? Anyway, my theory is that it is not the case here and, since this is an AVCHD file which is usually accompanied by other auxiliary files, I guess that explicit marking of random access points in the stream is usually not necessary for hard/software that relies on the AVCHD spec being followed, because they are stored in a separate file (my assumption, for which I have no proof). The bad thing is that I haven't found a version of the spec online and it costs a lot of money, so I cannot check this immediately. Anyway, it does not help much in deciding how ffmpeg is supposed to decide it is a random access point. Btw, is it intentional that you don't answer questions I ask in my emails? It feels a bit impolite to be honest. I don't remember not answering a question you have asked. _______________________________________________ Libav-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/libav-user
