[Bf-funboard] 29.97fps?

[Robert Wenzlaff (AB8TD)]

On Wednesday 26 March 2008 05:47, Sangwoo Hong wrote:
> This is not a problem for the PAL set but I happen to live in an NTSC
> country and have had to use 30fps to edit footage meant to be put on a NTSC
> DVD which gave me some sync issue which I had to offset the audio to fix. 
> I can't imagine this issue will be high priority but it would be nice if we
> could work in 29.97fps.

And Tom M answers:
 
> Already done in current SVN...

That's nice, but there's still a need for other fixes...

The animation system is based in frames, not seconds.  This means to re-render 
for another format, you have to re-time your animations.  But a few simple 
options that are standard methods for converting common frame rates would 
handle many situations.

The standard fix to convert film rate (24 fps) to NTSC is to repeat the 1st 
frame for 3 fields, and the 2nd frame for 2 fields (3rd 3, 4th 2...).  This 
is called 3:2 pull down and it converts 24 fps to 60 fields/s.  To get to 
29.97 fps, you then repeat 1 video frame every 1000 (1000:1001 pull up).

To convert film to PAL, you speed up the sound 4% and let it run short...

By having those options available, you could animate a scene at 24 fps and be 
able to convert to either PAL or NTSC in the industry standard way.  

I hope that when the major rev. comes, the animation system will all be in 
seconds, not frames (or at least have the option to choose) so you don't have 
to re-time things.

-- 
*********************************************
My Dad: Well, we don't need to get the 
        thank you cards out _right_ away.
Me:  Sure, they'll wait. I haven't even sent
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*********************************************
Robert Wenzlaff   rwenzlaff at soylent-green.com