[Ffmpeg-devel] [ bug ] converting png to dv gives solid black

Christian Iversen chrivers
Sun Mar 12 17:24:51 CET 2006


On Sunday 12 March 2006 16:06, M?ns Rullg?rd wrote:
> Christian Iversen <chrivers at iversen-net.dk> writes:
> > On Sunday 12 March 2006 15:35, M?ns Rullg?rd wrote:
> >> Erik Slagter <erik at slagter.name> writes:
> >> > On Sat, 2006-03-11 at 23:20 +0000, Dieter wrote:
> >> >> > > ffmpeg -i checkerboard_3x3_%d.png -r 30001/1001 -pix_fmt yuv411p
> >> >> > > tmp.dv
> >> >> >
> >> >> > A question unrelated to your problem:
> >> >> > Why not use -r 30000/1001 ? That's the official value for 29.97fps.
> >> >>
> >> >> Because that's what Erik recommended.
> >> >>
> >> >> Hmmmm... google finds a *lot* more hits for 30000 than for 30001.
> >> >
> >> > Besides the fact that either 30000/1001 and 30001/1001 are completely
> >> > stupid from a design point of view, I see both equally often. Actually
> >> > I think I don't even want to know which one is correct :-p
> >>
> >> The common frame rates are 24000/1001, 24, 25, 30000/1001, 30, 50,
> >> 60000/1001, and 60 fps.  30001/1001 is very unlikely to be correct.
> >
> > Where do these /1001 come from, historically?
>
> It reduces visible interference between the chroma and audio signals
> in an analog broadcast.  No, NTSC is not a particularly good system.

Understatement of the year :-)

-- 
Regards,
Christian Iversen





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