[mythtv] [PATCH] time stretch with libsoundtouch

Mark Spieth mark at dclabs.com.au
Thu Nov 4 22:57:17 UTC 2004


> I didn't look at the patch too hard yet, but in terms of control keys,
> we already have a speedup and slowdown option.  Did you piggyback onto
> that code?  (Which is probably the best way I think?).

yes that is what I used for the control. there is a flag which says normal
or not in nuppelvideoplay::play(). normal means turn audio on with the
appropriate speed factor.

>
> Ed W
>
> P.S. If you wanted to fix something interesting, then I would personally
> love to be able to do like 25x speedup or more - ie for forwarding
> through the adverts.  Because the current method decodes all frames, I
> currently run out of processor power at around x6-x10 or so (I think?).

shouldnt this be ok if you just decode I frames and ignore the P and B ones?
that should reduce the processing by quite a bit. Ill have a look if it
hasnt been done before. but surely it has???
I like the 30sec jump for ad skipping. much faster than scanning. about
3secs to skip an add. auto detect isnt that relable for me.

I also notice that the quality of decode is not as good as on my windows
machine. dark backgrounds get a lot of dark green amongst the nearly black
background. use brightness control to enhance this effect. I think this must
be a rounding error in the video decode routines.
mark



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