Hi, On Wed, May 18, 2011 at 9:03 AM, Vittorio Giovara <[email protected]> wrote: > So just to reflect the discussion on the chan, it is fine to reject this > patch as it breaks FATE. > > However I still believe that the behaviour introduced in my patch would be > much more consistent for different videos: I mean why is it fine for a video > to crop 24 lines because it is interlaced, but you can crop max 14 in case > of progressive? Imho it is better and more consistent to always crop max 8 > lines independent of resolution and framerate.
The logic (which is flawed, but still) is that for interlacing, you may be interleaving two MBs and cropping lines from both. Thus, you would - at most for a logical case where you don't want to waste MBs that are being skipped anyway - want to skip up to 30 lines. For progressive, this would be 15. In both cases, skipping more lines means you skipped a complete MB and you could as well not have coded the MB anyway, thus suggesting the encoder is retarded or the bitstream broken. But realistically, if the encoder wants us to skip more, well, then let's skip more. Maybe these are invisible MBs used as prediction (of off-frame content) for future frames, e.g. in case of a zoom-out scene? Maybe the encoder is playing magic here. Jason can probably confirm that there are cases where this may be beneficial. Ronald _______________________________________________ libav-devel mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-devel
