[MPlayer-dev-eng] [PATCH] mencoder precised/exact seeking

[Rich Felker]

On Thu, Apr 12, 2007 at 05:46:27AM -0700, Trent Piepho wrote:
> On Wed, 11 Apr 2007, Rich Felker wrote:
> > > Of course this is very slow, and most filters don't care about missing
> > > frames, so your patch is an improvement in almost all cases.
> >
> > It's not. There's a correct way to do skipping involving vfctls, where
> > the softskip filter is inserted after all the filters that need to see
> > all frames. Copy that code.
> 
> There is still the problem of decoding every frame during a skip, instead
> of just seeking over them.  If softskip is the first filter it is still
> very slow to decode every frame just to drop it without using it.

Skipping decoding is impossible. When you get to the frame you finally
need you won't be able to decode it because you'll be missing the
previous frame.

> telecine filter doesn't see that.  Why does it need to see the hour of
> material before what I want to encode?

As the length of the pre-interval it sees increases, the probability
that it will have the same phase decisions as if it had infinite
lookback approaches 1. However knowing what length is needed is
difficult and there is no clear answer in the general case...

Rich