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

[Måns Rullgård]

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.

-- 
M?ns Rullg?rd
mru at inprovide.com