[FFmpeg-devel] [PATCH] mov: support for Quicktime CLEF/TAPT atoms

Michael Niedermayer michaelni at gmx.at
Tue Jul 3 17:04:57 CEST 2012


On Tue, Jul 03, 2012 at 04:50:49PM +0200, Nicolas George wrote:
> Le sextidi 16 messidor, an CCXX, Tim Nicholson a écrit :
> > This sounds like the right approach. However where can you currently
> > define the pixel rectangle for which the DAR is calculated? For example
> > the setdar filter allows the DAR to be set and calculates the SAR on the
> > basis of the equation I quoted.
> 
> As far as I know, a SAR field is always part of a structure such as AVFrame,
> AVCodecContext, AVFilterLink, AVFilterBufferRefVideoProps, etc., and these
> structure always have a pair of width, height fields. These three fields
> work together.

AVFrames also have pan_scan that allow active rectangle to be exportet
that can be a 4:3 and a 16:9 rectangle for example and these can
move around through the movie to keep the best selection for each
aspect ratio.

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Rewriting code that is poorly written but fully understood is good.
Rewriting code that one doesnt understand is a sign that one is less smart
then the original author, trying to rewrite it will not make it better.
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