[FFmpeg-devel] [PATCH 06/13] avformat/mxfenc: Add Sample width/height/x offset/y offset, Display x offset and F2 offset

Michael Niedermayer michael at niedermayer.cc
Fri May 11 00:32:09 EEST 2018


On Thu, May 10, 2018 at 10:48:59PM +0200, Tomas Härdin wrote:
> tis 2018-05-08 klockan 18:26 +0200 skrev Michael Niedermayer:
> > On Tue, May 08, 2018 at 12:40:49PM +0200, Tomas Härdin wrote:
> > > mån 2018-05-07 klockan 12:38 +0200 skrev Michael Niedermayer:
> > > > > Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> > > > 
> > > > +    if (sc->interlaced) {
> > > > +        //Display F2 Offset
> > > > +        mxf_write_local_tag(pb, 4, 0x3217);
> > > > +        avio_wb32(pb, -((st->codecpar->height -
> > > > display_height)&1));
> > > 
> > > Negative values for DisplayF2Offset are not valid
> > 
> > The specification (SMPTE 377-1-2009) says:
> > 
> > The DisplayF2Offset Property adjusts the DisplayYOffset for the
> > second field relative to that for the first field. Its
> > value shall be zero (0) or minus 1. A value of minus 1 shall invert
> > the Displayed Topness relative to the Sampled
> > Topness.
> 
> Huh, the document I have is from 2004, which says "If the property is
> not present, its value shall be assumed to be 0. Valid values are zero
> or 1.". So I guess they changed that. I guess it's fine then.

will apply

thanks

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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