[mythtv-users] Two odd issues with NBC DTV recordings

[Yeechang Lee]

Tom Dexter <digitalaudiorock at gmail.com> says:
> > I am recording _Knight Rider_ right now as a test.[1] MythWeb
> > shows a proper preview image. I use 305 as my offset.
> 
> Thanks for the test.  I recorded one show off NBC last night and got
> a black preview.

I spoke too soon. I recorded another show, _Lipstick Jungle_, as a
test, and that generated a black preview. The _Knight Rider_ recording
generated an almost-black preview that did have a visible blue Ford
logo in the middle so I had thought the preview was correct, but now
am not so sure.

Rebuilding the seektable, as mentioned elsewhere in the thread, and
forcing the preview to regenerate by deleting the filename.png and
filename.100x56.png files[1]--I don't know of another way to force the
MythWeb preview image to regenerate--created a proper preview image
for _Lipstick Jungle_.

Going back throught the start of the year, I found several other
recordings with black preview images. Three were from Starz HD via
FireWire and one each was from HDNet Movies via FireWire, CBS OTA, and
PBS OTA. (Not all Starz HD recordings from 2008 had this issue.)
Rebuilding seektable produced proper preview images from the Starz HD
recordings but not the others.

A couple of other points for those mulling over the issue:

* Tom is in NYC, and I am in San Francisco. These are two of the metro
  areas that recently gained a new SD multiplexed OTA channel,
  Universal Sports. As a result, my NBC affiliate decreased its
  bitrate for HD broadcasts so that formerly ~7.5GB/hour recordings
  are now ~5.5GB/hour.

* Also, NBC recordings that came in as ~51 minutes per hour
  (<URL:http://www.gossamer-threads.com/lists/mythtv/users/227272#227272>)
  in the OSD over the past two years now again appear as an hour. I
  suspect, but can't be sure, that the change occurred along with the
  bitrate change. (The ~51-minute issue only affected prime-time
  shows, not the videotaped late-night talk shows.)

[1] Don't forget to clear your browser cache.

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