[mythtv] sound during fast forward/rewind on pvr350 when using it for tv-out

[jose rubio]

On Fri, 2004-03-19 at 16:07, Joseph A. Caputo wrote:
> On Friday 19 March 2004 15:38, jose rubio wrote:
> > On Thu, 2004-03-18 at 12:45, Joseph A. Caputo wrote:
> > > On Thursday 18 March 2004 11:57, Simon Kenyon wrote:
> > > > David Engel wrote:
> > > > >On Thu, Mar 18, 2004 at 01:49:44PM +0000, Simon Kenyon wrote:
> > > > >>with ivtv-fb. when i fast forward to rewind then it plays brief
> > > > >>sequences of video as it goes. unfortunately, it also plays
> > > > >> brief snatches of audio as well, which IMHO is annoying. this
> > > > >> does not
> > > > >
> > > > >It's a known problem.  I don't know when it will get fixed since
> > > > > it requires a significant change to the way Myth does ff/rew.
> > > >
> > > > oh well. i'll have to live with it so
> > > > thanks for the quick answer
> > >
> > > You could use the 'trick play' feature instead of bona-fide ff/rew.
> > >
> > > Pro/cons:
> > >
> > > + gives 'smooth' rather than 'jumpy' ff/rew
> > >
> > > - requires more CPU, as it actually decodes every frame, as opposed
> > > to skipping them like ff/rew does
> > > - max. speed is lower than ff/rew
> > >
> > > That said, I think ff/rew should be able to be re-worked so that it
> > > doesn't play sound.  Trick play obviously does it.
> > >
> > > This has been an item on my list for a long time.  I wrote the
> > > initial implementation of the current ff/rew behavior, and at the
> > > time there was no clean way to mute the sound during ff/rew without
> > > modifying NuppelVideoPlayer, which Isaac didn't want me to do at
> > > the time.  Later the 'mute' functionality was added, and I thought
> > > I might be able to utilize that, but it would have been a kludge,
> > > and since the mute function doesn't maintain state, there was no
> > > elegant way to determine if the sound should remain muted or not
> > > when exiting ff/rew.  Then the trick play features were added, and
> > > I seem to recall ended up touching NuppelVideoPlayer to do
> > > things... I guess the author was able to make a better argument
> > > than I did at the time.
> > >
> > > Maybe I'll revisit this, but actually it's not a priority right
> > > now; I think I'm going to remap my ff/rew keys to do trick play. 
> > > Anyone else is welcome to take a stab at it...
> > >
> > > -JAC
> >
> > OK so I'm gonna sound stupid here but...
> >
> > What is the 'trick play' feature?
> 
> Speed up/slow down playback.  According to keys.txt:
> 
> - U to increase the play speed
> - J to decrease the play speed
> 
> This is different than ff/rew, as I've described... the 'trick play' 
> features give a smoother playback, since they're not skipping frames 
> but simply changing the playback rate.  For fast playback this of 
> course this means decoding more frames per second, so it comes at the 
> expense of a higher CPU load (if I had to guess, anyway).
> 
> -JAC
Oh yes, I've tried that.  Only problem is that the fastest it goes is
3X...  Took a quick look at the code and it seems to allow up to 5X. 
Don't know much about the code though :-( so I'm not sure if I could
make it go faster.  Do you know?


-jose-