white flashing lines at top of digital channels?

[jdabling]

Hey all,

I've got some white flashing lines at the top of some (not all) of my digital channels (OTA), but never the analog OTA channels. Attached is a screenshot that shows a single frame - you can see faded white lines at the top. They are much more noticeable when they are moving around at the top of the image, sort of like visual noise.

Is this my hardware? I don't think it's software (GBPVR), as I am pretty sure this showed up in media center as well.

Any ideas?

[TonyXL]

It's closed caption data. The analog driver is probably set to crop them out, but the digital side is just letting the full image through. You should be able to tweak the aspect ratio (or a similar setting) in config.xml to crop out the top few lines.

[johnsonx42]

On my system I output to a TV via SVideo, so I just put in a little overscan all around using Catalyst Control Center.

If that's not an option for you, can use negative aspect ratio numbers in the <AspectRatioMode> lines if you are using the VMR9 renderer (either custom or FSE), but it won't work with Overlay or EVR (much to my dismay).

Something like this:
<AspectRatioMode name="Fill" ratio="0,-0.02,1,1" />

will pull the top edge a little off the screen. I'm assuming based on your screen shot that you're using a 16x9 or 16x10 screen shape - the line I offered would replace the same line in the appropriate section. You can tweak the -0.02 as needed.

There are also some other settings in config.xml I've never played with, but might do something for you:

<!-- zoom control -->
<HorizontalZoom>1.05</HorizontalZoom>
<HorizontalOffset>0</HorizontalOffset>
<VerticalZoom>1.03</VerticalZoom>
<VerticalOffset>0</VerticalOffset>
<CropVBI>true</CropVBI>
<!-- overscan control (border size in pixels) -->
<OverScanBorderX1>0</OverScanBorderX1>
<OverScanBorderY1>0</OverScanBorderY1>
<OverScanBorderX2>0</OverScanBorderX2>
<OverScanBorderY2>0</OverScanBorderY2>
<OverScanVideoAlso>true</OverScanVideoAlso>

Perhaps a negative number for VerticalOffset? Or maybe a negative number for <OverScanBorderY1>? Not sure exactly what effect these settings have. Interested in your findings.

[mc510]

I've got the exact same thing as jdabling, except that what I want to do is crop those flashing lines off the top while recording, rather than while playing (because I usually playback on my set top dvd player). This probably isn't possible, right? Would I have to have a postprocessing step to crop and re-encode?

[martint123]

what I want to do is crop those flashing lines off the top while recording, rather than while playing (because I usually playback on my set top dvd player). This probably isn't possible, right? Would I have to have a postprocessing step to crop and re-encode?

With digital, the data is just read from the tuner and written to disc direct. So it would need some later stage to chop the top off (sorry, no suggestion as to what program to do it).