[FFmpeg-devel] DV Video and SAR

[Charles Yates]

2009/10/18 Baptiste Coudurier <baptiste.coudurier at gmail.com>

> Thanks, applied.


Much appreciated :-).


>
> This one looks ok as well. I'll apply it soon I think.
>

Good - thank you.


>
> I was wondering if we shouldn't set sar for dv to digital sar as opposed to
> analog sar considering mpeg-2 sar and how FFmpeg deals with sar in general.
> Any opinion ?
>

I am not sure what you mean there - to the best of my knowledge, the SAR's
reported for DV and mpeg2 are (pretty much) spot on.

I'll stick to 'pretty much', cos all the SD values are approximations anyway
- ie: 720 * 59 / 54 != 788 (should have that, thus leaviing 10 samples on
left and right which is the overscan and the central 768x576 being the true
4:3 image) - but I think they were chosen to be uniformly expressed as a
pair of bytes or some similar olde worlde consideration? Is that the issue
you were referring to?

Either way, I think the SAR evalutions provided are fine - just feel that
standardising the location (on AVFrame) would be nice, though it'd also be
kinda nice to know from an arbitrary packet (prior to decode) as well :-).

Cheers,

Charlie