[mythtv] RFC: Expanded playgroup settings

[Scott D. Davilla]

>Am Montag, 3. Dezember 2007 schrieb Kevin Kuphal:
>>  This is a short patch that I'm working on currently that adds the
>>  ability to set the Video Scan method in a Playgroup in order to, for
>>  example, force interlacing for stations that broadcast a mix of
>>  progressive and interlaced frames which throws off the Auto-detector.
>

I too am plagued with this on OTA ATSC 1080i stations. The rapid 
switching back and forth on my setup is causing problems as the 
frontend tries to keep up. Eventually there's some deadlock condition 
between the various locks/unlocks and then the frontend freezes and 
has to be killed. It's going to be vary hard to find the real cause 
as it's a classic race condition whose behavior is going to change 
under debugging attempts.

Seems like there are the following condition regarding playback;

a) The interlacing is unknown and NuppelVideoPlayer needs to figure it out.

b) The interlacing is known and NuppelVideoPlayer need to stop messing with it.

Looking over the two mailing lists (dev, user) indicates that this 
issue really only happens with 1080i broadcast. Real world conditions 
indicate that 1080i broadcast can have frames change from interlaced 
to progressive and back. Sometimes at a high switch rate. Why, not a 
clue. Calling the station is not going to get it fixed as it's a 
content issue. The station is just merging content from different 
sources and doing the broadcast. Not their problem.

My humble opinions in tracking my random frontend freezes while 
viewing 1080i content. 720p content is perfect.

Scott