[mythtv] [Experimental PATCH] New FF/Rew mode

David Engel gigem at comcast.net
Mon Nov 8 18:40:32 UTC 2004

On Sun, Nov 07, 2004 at 09:32:49PM -0500, Jeremiah Morris wrote:
> On 7 Nov 2004, at 8:34 PM, David Engel wrote:
> >This patch reworks the fast-forward/rewind mode to hopefully be
> >smoother and provide more accurate timing.  I think it's close enough
> >for me to commit but I'd like to get some feedback before doing so.
> Mark Spieth is currently working on fast-forward and slow-motion with 
> the purpose of integrating libsoundtouch.  I'd suggest taking a look at 
> his work and collaborating to ensure a solution to his issues as well 
> as yours.

I haven't been following that work so I took a look at the latest
patch.  There is some overlap in the control logic, but the two
features are quite different and don't overlap.  My ff/rew change aims
to synthesize moderate to very high speeds by only playing selected
key-frames and adjusting the frame interval accordingly.  Trying to
provide intelligible audio at those speeds would just be silly.  My
change also aims to make ff/rew usable on the pvr350 where it
currently isn't, IMHO.

I have a couple of other comments regarding Mark's patch.

First, I think stretch mode speeds should be controlled separately
from the existing fast/slow motion because I see them being used for
completely different purposes.  I use the existing fast/slow motion
for doing my own "slo-mo" replays or quickly getting through a short
section without discarding any video.  I see the the strech mode as a
semi-persistent, adjustment of the nominal play speed.  I would set it
and then expect it to resume at that speed after seeks and pauses.

Second, the pvr350 can support adjusted audio at 0.5x and 1.5x speeds.
It would be nice if stretch mode supported the pvr350 too.

David Engel
gigem at comcast.net

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