On Sat, 2009-09-26 at 15:33 -0700, Rob Starling wrote: > On Sat, Sep 26, 2009 at 06:05:50PM -0400, Andy Walls wrote: > > On Tue, 2009-09-22 at 08:44 -0700, Tony Sarathchandra wrote: > > > > > > Hi all, > > > I've been running a split FE/BE Mythtv setup with minimal > > > issues almost for a year now. On the BE I'm using a HVR-1600 to > > > receive OTA HD via the ATSC input from a roof mounted antenna. The > > > issue has been that on some channel, and some channels only I've been > > > getting what appears to be interlacing/combing effects. I have an > > > example of this effect from the capture here on start of 60 minutes on > > > CBS (4_2 KPIX-DT in the Bay Area). The effect is very pronounced > > > during horizontal motion involving particularly vertical features in > > > the picture. > > > > > > http://thinkspace.ath.cx/stuff/vlcsnap-2017280.png > > > > I suspect you only see this on 1080i video and not 720p. > ... > > > The effect is present independent of the player, whether it's on the > > > Mimimyth FE I normally use, XBMC or VCL on my PC in this case, hence I > > > put it down to a reception/BE issue regarding the OTA signal quality > > > reception for these stations. > > > > Hmmm. Well, this is a known effect with 1080i. You must have "young" > > eyes; I tend not to notice the effect that much. > > is it relevant that the CBS logo in the lower-right does not > appear to show the combing effect? that would seem to indicate > to me that the erroneous converstion is happening at the CBS > station itself before superimposing the logo, no?
Rob, I've only every seen the effect in 1080i HDTV with objects that move in the frame. The CBS logo is always in the same position on the frame, so it would never show the effect. However, that does not rule out the possibility that the conversion to digital at the source is doing a poor job, as you suggest. I would think CBS has the money and experience to get this sort of stuff right, though. Regards, Andy > --Rob* > _______________________________________________ ivtv-users mailing list [email protected] http://ivtvdriver.org/mailman/listinfo/ivtv-users
