Grey bars when watching video that doesn't match screen size when "use limited color range" setting is disabled

Aye; this was only to try to address the issue coming from Vero/OSMC/Kodi. It’s literally the only device I’ve played these files on that has the problem.
I don’t mean to sound rude but I must repeat: the video itself plays with perfect black. it is literally only the letterboxing above and below the video.
Is there some kind of background while the video is playing, which is grey?

I know exactly what you are saying, and I can reproduce it but only if sending RGB full-range to the TV. It is as if the letterbox mattes are being inserted at level 16, on top of a full-range picture, but I’m not clever enough to find out why. kernel 4.9 does it differently which should solve that problem (it does solve it here). Some people on the team do have LGs and we are testing 4.9 now so we should be able to fix it.

Ahh, grand. Yeah happy to wait for the next release anyway.
Thanks so much for your help, patience, and time :slight_smile:

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Ah, grey bars with cropped movies… My solution is padding with xmedia recode and the movie is fine on my LG c9. With padding you restore the movies original size with filling it with black-black bars.

GrTz
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Knowing nothing about recoding videos; would that be lossless? In my case, I can run the video from PC to TV anyway so wouldn’t spend the time converting. Thanks for the tip! :slight_smile:

This strongly suggests your television is not calibrated correctly. If you could configure your TV correctly and then use limited-range video, you might find the problem disappears. Overall image-quality will likely improve a little too.

I’m pretty sure this is rested on getting an update.
I don’t believe the tv is at fault, like i said the video itself has perfect black, and osmc on vero is the only input doing this.
What about then quote makes you think it is the tv, and exactly what tv settings do you think could be wrong?
Thanks for input! :slight_smile:

Digital video is stored in limited-range format, and TVs expect limited-range YUV input, and display with optimal image quality when they are fed that. Full-range RGB signals are generally only used as the output of a device like a PC or as the input of a dedicated PC monitor.

Quite what you may have done to the TV to make it behave like a PC monitor, I wouldn’t like to say with any certainty. It could be all sorts of things - the wrong Brightness setting, the wrong icon assigned to the input (you said it was an LG TV, right?), some other setting that specifies what type of input signal it’s expecting… I don’t know. But I do know that limited range is the input it should be expecting, and if it isn’t displaying that correctly, it’s set up wrongly.

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Thanks again, @angry.sardine .!

I just can’t reconcile tv misconfiguration while the video is showing perfect black (added image) and have already exhausted searching through tv configs. OSMC input is configured exactly the same as every other input.

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Edit to clarify: the image is top left of tv showing the grey band on top (letterboxing as video resolution doesn’t fill vertical) and perfect black contained in the video which is being played.

With a full range signal, black is 0 and white is 255. Limited range means black is 16 and white is 235. The video is stored in limited range format.

You’ll get the correct black level in the video if either the source’s output is full range and the TV is set to expect a full range signal, or the source is limited range and the TV is expecting limited range. Right now you’re using the first of those two combinations; but using limited range video throughout will give you a slightly improved picture relative to that, because you don’t have to transform between colour spaces (which reduces accuracy).

Now, there clearly is a bug in the source device, here, in that it isn’t rendering the black bars in the correct colour; but Graham says he can only reproduce that issue when using full range output. So it seems highly likely that using limited range source video, and also setting up the TV to expect limited range, will not only give you an improved image quality, but also work around the black bar problem as well. Limited/limited will therefore solve all of your problems.

Thanks, but it doesn’t unfortunately. Hopefully the update will do the trick :slight_smile:

What did you change on the TV to make it expect a limited range signal?

This discussion was pretty useful; it seems the “Black Level” is the main option on LG; though there are a few other configs labelled re black/bright/etc.

Well, even if using limited range video doesn’t fix your black bars issue, you should keep using it anyway. That’s the best signal format to use if your display is a TV.

Honestly thanks for the input, but there are already several posts above about why thats also not true.
Namely: The entire picture will become washed out (no more black at all)

Have you seen and resolved this exact issue on your own display? What exact tv settings did you change on your tv, i can google the lg equivalent.

You said yourself, as did Graham that there’s obviously something wrong with how the bars are grey and the video isn’t. Still happy to wait for the new version :slight_smile:

Thanks again.

I just ran into this thread by accident while searching for a clue why my letterbox looks all grey on my LG CX.
Hmmm, odd. Who knows there is a solution in our near future…

I feel like we’re going round in circles here. If blacks are washed out when you send a limited-range signal to your TV, it is because your TV is configured wrongly. All TVs are optimised for limited-range sources - that’s not a matter of opinion, it’s a matter of fact. Yes, you can configure a TV to behave like a PC monitor, but you will likely not get optimal results when you do.

So, you haven’t actually tried doing what I suggested yet. What I suggested doing was to set the source to limited-range, and then adjust the TV settings until it looks right. Once you’ve done that, I wouldn’t be at all surprised if it fixes your black bars problem; but you won’t know until your TV is correctly configured.

Living up to your name, buddy.

You should get closer with the “black level” on auto or low, but its not perfect, for me anyway, unfortunately.
Edit: use that in combination with the limited range btw. Toggle through combos of these two.

It’d be great to see Herculainn1’s video problem solved, but let’s not thread jack too heavily.

This thread was started as a support request because of the grey bars that OSMC is errantly rendering (and has been since at least 2019) for videos that don’t match the output frame size. No amount of messing about with TV settings will fix that bug in OSMC/Kodi.

Discussion of limited range being better than full range should probably be saved for more relevant threads.

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