[Libav-user] Criteria for h.264 key-frame detection

[Carl Eugen Hoyos]

Robert Krüger <krueger at ...> writes:

> I just cut away everything from the file until the start 
> of the packet containing the 27th frame 
> (tail -c4329532 gh1_720p.mts > gh1_720p_cat.mts) and the 
> resulting file decodes without artifacts using ffmpeg.

(With or without -flags2 showall?)

> The number of decoded frames is also as expected. So I
> think this is at least an indication that the 27th 
> frame is indeed a valid random access point.

I don't think the fact that a frame can be decoded 
(correctly) implies that it is a random access point.

Carl Eugen