Screen Fit - Missing Pixels

Channels Apple TV
#1

Hello.

I’ve recently started using Channels on my Apple TV using a HDHomeRun Prime.

I have a Samsung plasma (PN51F8500) and have the picture size set to “screen fit”. Using this mode, there is no overscan when checking in the Apple TV settings (Audio and Video > Calibrate > Zoom and Overscan).

When I launch the Channels app, all of the pixel rows are filled. However, when I watch live TV, some of the channels are not using several rows of pixels at the top. If I try to re-center the picture in the TV settings, then pixels are missing at the bottom. This is most noticed on the channels NBC and ABC.

I can change the TV setting to “16 x 9” from “screen fit” and this allows all of the rows to be used but there is overscan present (the bottom is chopped off).

Any ideas why this is happening?

Thanks,
Patrick

#2

Can you snap some photos?

#3

This week I tried a HDHomeRun Connect to see if it has the same issue. It seems to do the same thing.

I tried to upload pictures a few times but the system is always stuck at “Uploading 100%”.

#4

I’ve been using WMC and don’t see this issue with the same settings on my TV and WMC set to 1080P (using a 2010 Mac Mini to run WMC via Win7 bootcamp)

I would love to figure this out because Channels is a much better experience compared to WMC :smile: The only thing is that the missing rows of pixels drives me crazy!

#5

Can you try some other apps on the ATV, like the free apps “instatv pro” and VLC

You can email photos to [email protected] as well.

#6

I have the Samsung plasma PN60F8500 and have the same experience but only on some channels(NBC). Its the same when viewing those channels with VLC or IntaTV,

#7

I also tried InstaTV and see the same issue there (just like Scott).

For me, the issue is worst on ABC (WXYZ HD - 720P).

The problem is the same using either a Prime or Connect box.

I sent a PDF with some pictures and descriptions to the support email address.

#8

@helmanps sent me a sample recording from his HDHR, and it looks like there's 9 pixels worth of black pixels at the top directly in the source. Not sure why it's being broadcast this way..

I will have to do some research to see if/how this can be detected and fixed. FWIW, the same issue shows up even when watching the recorded file via VLC.

Here's a single frame extracted from the video I received.. you can see the black bar at the top:

#9

Can you try the “HDHR View” app on a mac/windows computer to see if shows the same issue?

#10

Same issue when using the HDHR View app.

#11

I looked into this a little more. Apparently, WMC adds slight overscan to Live TV and Recorded TV if the display setting is set to “flat panel”.

If you change the display setting to “television”, the overscan is disabled and I see the same missing rows of pixels in WMC as seen in Channels, InstaTV, etc.

I also read a few discussions that indicated black bars may be seen on the top of a broadcast TV if the broadcaster was not careful with VBI settings when creating the video file.

I realize that overscan is not desirable. However, I can’t tell the difference in picture quality between playback of a slightly overscaned WMC recording versus a Channels recording but do like not having the black bar. Would it be possible to add a setting to enable slight overscan for live TV and recording playback in Channels?

Here’s a link that discusses WMC overscan:

https://www.missingremote.com/guide/missing-remote-tips-and-tweaks-2-preventing-sneaky-tv-overscan-windows-7-media-center

#12

Yea an overscan setting seems like the best bet here. I’ll see what we can do…

#13

Hello. Any chance you’ve had time to look into this?

#14

you could set your TV to zoom instead of screen fit. That would fix the bars on the sub-par cable channels you are receiving.
Alternatively, since you have a connect, did you try it with an antenna? I would bet that the major networks are broadcasting OTA correctly, ie: it is probably your cable provider causing the issue.

#15

Sorry I lost track of this because we got busy with the DVR.

Do you know how many pixels of overscan WMC applies?

#16

An overscan option has been added to the latest beta. Please try it out and let me know if it resolves your problem.

#17

dude, you guys work fast!

#18

Thanks for the fast response. I downloaded it and will use for the next few days and then let you know. I’ll also take a closer look at WMC to see how much overscan is applied.

#19

@helmanps Did the new option fix your issue?