[mythtv] Ticket #7964: Predictively skip frames to smooth out timestretch

[John P Poet]

On Sun, May 9, 2010 at 11:11 AM, David Engel <david at istwok.net> wrote:
> On Sat, May 08, 2010 at 10:30:15AM +1000, Mark Spieth wrote:
>> ive uploaded patch 6 which is the same as 5 but moved up my patch
>> stack so there should not be any apply issues.
>
> Mark,
>
> Are there any known reasons why your patch won't work with 0.23-fixes,
> other than having to manually apply some parts?  v5 worked fine on
> 1080i, and on 720p at normal speed.  It didn't work very well on 720p,
> however, when timestretch was used.  After a skip, the video would
> stop updating and it could never resync until timestretch was turned
> off.

David,

I finally upgrading to version 5 of Mark's patch and also notice that
skipping around in a video causes issues.  General playback (with
timestretch) is fine, but it can take several seconds for playback to
become smooth again after a skip -- If there is a ticker-tape on the
screen, it will be a bit jerky for a few seconds before smoothing out
again.

A couple times, skipping backwards seem to completely confuse it and
playback completely wedged up.  Skipping forward got it playing again,
though.

This is with 1280x720p60 recorded from ATSC (mpeg2) and from my HD-PVR (H.264).

In general it is a major step forward and is very usable, but
commercial skips are a bit jarring.

I have not tried combining Mark's patch with my predictive-skip patch
to see if it smooths it out any more.


John
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