[FFmpeg-devel] [PATCH v3] avformat/rtpdec_rfc4175: Fix incorrect copy_offset calculation

[Michael Niedermayer]

On Mon, Aug 05, 2019 at 06:05:29PM +0100, Kieran Kunhya wrote:
> On Mon, 5 Aug 2019 at 17:10, Michael Niedermayer <michael at niedermayer.cc>
> wrote:
> 
> > On Thu, Jun 27, 2019 at 06:06:22AM +0000, Jacob Siddall wrote:
> > > The previous calculation code did not account for the fact that the
> > > copy_offset for the start of the frame array is at index 0, yet the
> > > scan line number from the rfc4175 RTP header starts at 1.
> > > This caused 2 issues to appear:
> > > - The first scan line was being copied into the array where the second
> > >   scan line should be. This caused the resulting video to have a green
> > >   line at the top of it.
> > > - Since the packet containing the last scan line would fail the
> > >   calculation, the packet with the RTP marker would not be processed
> > >   which caused a log message saying "Missed previous RTP marker" to be
> > >   outputted for each frame.
> > >
> > > Signed-off-by: Jacob Siddall <kobe at live.com.au>
> > > ---
> > > Changes in v2:
> > >   - Don't handle packet if the line number is less than 1
> > >
> > > Section 12 in the VSF technical recommendation TR-03 specifies that the
> > > video scan line numbers should start at 1.
> > >
> > http://www.videoservicesforum.org/download/technical_recommendations/VSF_TR-03_2015-11-12.pdf
> >
> >
> SMPTE 2110-20 says line numbers start at 0. (Yes there are 3 different
> "standards" for handling the line number because of the geniuses in the
> broadcast industry).

Jacob, can you look into this ?

should i revert until this is fixed?

Thanks

[...]
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