Re: Fix for AV-sync with FFMPEGrec

[Billy Biggs <vektor@xxxxxxxxxxxx>]

Alan Cox (alan@xxxxxxxxxx):

> Converting NTSC/PAL is hard. Some of the DVD players do a good job and
> they don't get jerking on a slow pan. I'm not sure how they do it, but
> I'd guess someone is interpolating the mpeg motion vectors ?

  Now that I think about it, I bet they're using the cheap method of
motion-blurring adjacent fields as shown with the Simpsons example on my
web page:

  http://www.dumbterm.net/graphics/dvd/

  Basically, you convert by keeping two clocks, one at 59.94fps another
at 50fps, and if in your 50fps timeslice there's a switch from one frame
to another in the 59.94fps clock, you show a 50-50 blur of the two
frames.

  Quite sad, but very cheap to implement.

-- 
Billy Biggs
vektor@xxxxxxxxxxxx