[FFmpeg-user] Problem with DAR and SAR readout from AVCI-50 and DNxHD MXFs
Carl Eugen Hoyos
cehoyos at ag.or.at
Thu May 8 19:09:29 CEST 2014
Christoph Gerstbauer <christophgerstbauer <at> gmx.at> writes:
> So you mean a SAR or DAR with "0:1" already means "undefined"?
First, there is not DAR:
There is a resolution and the sample aspect ratio (sometimes
called pixel aspect ratio) and that allows to calculate the
display aspect ratio and this is how it's shown on the
If the stream does not define a SAR (or if it is invalid)
then it will be set to 0:1 (or sometimes 0:0) which is
invalid (as you already correctly stated).
Note that it is very important to signal an invalid SAR
because files can define different SARs in the container
and the video stream and you need to decide which one to
The question is now if the dnxhd files you uploaded don't
contain a definition for SAR or if FFmeg fails to read it.
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