[FFmpeg-user] Setting Display Aspect Ratio of MXF/DV video
Carl Eugen Hoyos
cehoyos at ag.or.at
Tue Apr 14 01:13:27 CEST 2015
Marc Tarin <ch0d4 <at> free.fr> writes:
> The tests described below where run with an up
> to date FFmpeg release from the debian
> multimedia repository:
For future questions, please always test current
FFmpeg git head.
(Nothing else is supported here.)
[...]
> Stream #0:0: Video: dvvideo, yuv420p, 720x576 [SAR 16:15 DAR 4:3]
> A bit of context: the input file is supposed to
> be broadcasted in 16:9, but as you can see it
> is reported as 4:3 by ffprobe.
I am not sure I understand:
Do you mean that FFmpeg detects the aspect ratio
incorrectly? If yes, this should be fixed first
(and all remaining issues depend on this).
[...]
> $> ffmpeg -i in.mxf -vcodec copy -aspect "16:9" -an out_copy.mxf
This does not work because libavformat writes
mxf aspect ratio differently from all other
containers (sadly).
To some degree this is related to the fact
that mxf aspect ratio is defined in a rather
brain-dead way.
[...]
> At this point, my understanding is that
> the MXF container is always assigned a
> display aspect ratio of 4:3, even when it
> should be assigned 16:9.
This is certainly not true but as said, mxf
aspect in FFmpeg on muxing is different
from other containers.
(And this is a bug imo.)
Carl Eugen
More information about the ffmpeg-user
mailing list