[FFmpeg-user] on frame changes in recode

Xen list at xenhideout.nl
Fri Apr 29 12:51:15 CEST 2016


Moritz Barsnick schreef op 29-04-2016 11:02:
> On Thu, Apr 28, 2016 at 23:31:57 +0200, Xen wrote:
>> Basically there is no other information unless you want the number of
>> spaces typed on average every day on my system.
> 
> That would be very kind of you. I can recommend some keyloggers, but
> ask you to do the math for getting the average.

That's too hard on me, I need help.

Actually I do need help but not with this :p.

> I stepped through both the input video (downloaded using youtube-dl
> with your command) and "output.mp4" in two ways:
> - mplayer and the '.' key;
> - dumping frames to images using ffmpeg and "vsync -0" (I hope that's
>   correct for dumping exactly one output frame for every input frame).

Well I am just slightly amazed but I have the same result (with 
mplayer).

VLC still duplicates the frame.

Pitivi (probably using gstreamer to play it) also duplicates the frame.

So the issue is not in the rendering but in the player!!!! :@.

Alright that's stupid isn't it.

I'm not sure whether I've been stupid or the programs....

Thank you for checking in any case.... I'm sorry. If I'm an ass 
sometimes :p.

:).

> I'm happy just shutting my mouth and letting unresolved problems stay
> unresolved.

You're good that way :D.

> That is of course a quite valid issue, be it a bug or just incorrect
> use of ffmpeg.

Yeah...

What other players should I try. DragonPlayer is too stupid to exist and 
I cannot access any Windows tools right now, and possibly I would use 
VLC there anyway.

If your player starts inserting frames it means its actually framerate 
is either going to be higher, or the video will play longer.

They said films were often recorded in 24fps, when played on 25fps 
devices I think they would stretch it and the speed would go up and the 
pitch of the audio, shortening the film. But that requires actual 
playback to be of a higher fps.

In that case there would be no frame duplication or anything, just 
frames playing too fast. To do it right they would have to duplicate 
every 24th frame.

But that's probably impossible with audio or something, don't know.


BASICALLY:

input is 264, from YT, doesn't show artifact in VLC
output is 264, does show artefact in VLC
difference is new keyframe right before the duplicated frame?


Cheers I guess.


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