Digital Foundry Article Technical Discussion Archive [2015]

[dobwal]

Not that many Full HD tvs still do this, especially if they have game mode? I haven't seen one in real life yet anyway.

I bought a 55 inch Panasonic that did it. I was like "WTF" when I first used the calibration tool on the XB1 and I couldn't get the green bars along the perimeter of the screen to show. Had to fumble through the menus to find the setting to turn it off.

You would think initially setting the TV to "native" would have been all that was necessary, but my TV has a separate setting which confounds for me, panasonic's definition of "native" resolution.

 

[Scott_Arm]

Overscan is still a thing for some reason. I don't understand why. On my tv, I had to turn it off. It's only a couple of years old.

 

[Phil]

I've not had to correct a single PS4 game at least.

I actually thought about this for a while, but wouldn't this point to the fact that both the TV and your PS4 is set to overdraw enabled? You mentioned "game mode" in your earlier post, but to the best of my knowlege, game-mode and overscan are two seperate settings in many TVs. Game-mode simple disables most post-processing/filters and is unrelated to overdraw. At least, this is accurate for two Samsung TVs I've fiddled around with. As for not having to correct PS4 games - I definately have overdraw disabled on my projector and I'm pretty sure in most games (recently, that being Diablo 3, I think Alien Isolation and GTA5) that offer some kind of screen-size option at startup, I would have to expand the screen until it fits the edges. If I had overscan enabled, I'm fairly certain the default value would actually fit the screen perfectly.

Are you sure you have overdraw disabled and not just game-mode turned on? I know I'm making a point out of it in my post, but I think in reality, the lack of 1:1 pixel mapping is rather hard to spot in reality, just as differing resolution between Xbox One and PS4 games woud be...

 

[AlNom]

Overscan is still a thing for some reason. I don't understand why. On my tv, I had to turn it off. It's only a couple of years old.

Do broadcasters still have garbage at the outer edges for HD signals? I only have basic SD channels and there's sometimes unpleasant stuff at the edges.

 

[Scott_Arm]

Do broadcasters still have garbage at the outer edges for HD signals? I only have basic SD channels and there's sometimes unpleasant stuff at the edges.

Could be. I haven't had tv service in almost a decade.

 

[London Geezer]

Do broadcasters still have garbage at the outer edges for HD signals? I only have basic SD channels and there's sometimes unpleasant stuff at the edges.

What kind of unpleasant stuff? :neutral:

 

[AlNom]

What kind of unpleasant stuff? :neutral:

Signal errors/noise, funky lines.

 

[Scott_Arm]

I actually thought about this for a while, but wouldn't this point to the fact that both the TV and your PS4 is set to overdraw enabled? You mentioned "game mode" in your earlier post, but to the best of my knowlege, game-mode and overscan are two seperate settings in many TVs. Game-mode simple disables most post-processing/filters and is unrelated to overdraw. At least, this is accurate for two Samsung TVs I've fiddled around with. As for not having to correct PS4 games - I definately have overdraw disabled on my projector and I'm pretty sure in most games (recently, that being Diablo 3, I think Alien Isolation and GTA5) that offer some kind of screen-size option at startup, I would have to expand the screen until it fits the edges. If I had overscan enabled, I'm fairly certain the default value would actually fit the screen perfectly.

Are you sure you have overdraw disabled and not just game-mode turned on? I know I'm making a point out of it in my post, but I think in reality, the lack of 1:1 pixel mapping is rather hard to spot in reality, just as differing resolution between Xbox One and PS4 games woud be...

On Samsung tvs they're definitely different settings. If you turn on game mode, you can still use 16:9 setting, which will overscan. You need to set the tv to "Just scan" to get the 1:1 pixel mapping.

Kind of funny. People freak out about upscaling, but they're perfectly happy and unknowingly using over-scanning and weird 120/240Hz frame interpolation crap.

 

[goonergaz]

I find it amusing when I go to someones house and they have this ubber TV sitting on the corner and the PQ resembles SD due to incredibly poor settings

 

[Deleted member 11852]

Do broadcasters still have garbage at the outer edges for HD signals? I only have basic SD channels and there's sometimes unpleasant stuff at the edges.

Digital broadcasts based on the DVB standard shouldn't have because there is provision for other data in the standard. And it's not just for subtitles and teletext-style information. In the UK, and many parts of Europe, some TV manufacturers distribute firmware updates for their TVs over the air - typically at night.

 

[AlNom]

Digital broadcasts based on the DVB standard shouldn't have because there is provision for other data in the standard. And it's not just for subtitles and teletext-style information. In the UK, and many parts of Europe, some TV manufacturers distribute firmware updates for their TVs over the air - typically at night.

Guess it'll just be a matter of time before TV manufacturers deem it safe to not use overscan. Actually, do 4K tvs default to overscan currently?

 

[Deleted member 11852]

Guess it'll just be a matter of time before TV manufacturers deem it safe to not use overscan. Actually, do 4K tvs default to overscan currently?

I think the issue is with broadcasters who when re-broadcasting older material which has data encoded in the edges of the picture, will show as squiggles and crawling dots on any TV with overscan disabled. This is unless they adjust (crop) this during broadcast. Although it's becoming rare, I still this on occasion in the UK.

I guess Sony, Samsung, LG and Panasonic do not want customers phoning up saying they have squiggly lines and dots on their TV.

 

[HTupolev]

There would still be differences, the presence of scaling artifacts just wouldn't be one of them.

Unless said CRTs were receiving the common 480/576/720/1080 resolution standards, which easily could have been how things turned out in a world where flat panels hadn't taken over.

 

[joker454]

EDIT: Unless your point is that the PS4 version should also get a 900P framebuffer and just add more bells and whistles instead of raising the resolution..

Yeah that's basically it. Truth be told many companies would still just bump resolution and call it a day because that's the simpler and cheaper way to go about it, and with game development being such a savage risk nowadays I'd totally understand that. But other companies that also for example make pc versions of their game may be able to add a little more visual oomph to the ps4 version if they dropped resolution, since they are already coding said visual niceties for pc anyways means they can port them over. Or larger companies could take the extra time to add better textures, shadows, more involved lighting, etc, if resolution were dropped. Right now things seem to be headed to a holding pattern of 1080p 30fps first, and actual visual quality has dropped secondary in importance.

For those worried about upscaling artifacts, just add an a/v receiver. Even cheap ones now come with very high quality upscaling options over hdmi, and they also serve as nice hdmi switchers and home theater audio setups. Most people would not see a difference anyways as 1:1 typically still defaults to "off" on new tv's, so most everyone is already dealing with tv scaling whether they realize it or not. This is partly because there are still many people watching standard definition channels on their flat panel hdtv's, and when you set your tv 1:1 often you see garbage at the top on those channels. Until that changes I suspect 1:1 will always default to off even on new tv's.

 

[function]

Unless said CRTs were receiving the common 480/576/720/1080 resolution standards, which easily could have been how things turned out in a world where flat panels hadn't taken over.

Then you'd stick to the vertical resolution and scale horizontally at scanout, like consoles always did (MD / SNES / PC Engine / Saturn / N64 all had different horizontal resolution modes, and always looked "boss" on a CRT). I still have my Megadrive and RGB cable - unfortunately I had to bin all my CRTs....

Closest thing to this in the digital/LCD age is probably the Xbox One doing horizontal-only lanczos scaling. And that seems to work really well, going by raw captures.

If the PS4 has the Xbox one's scaling options, then on some titles you'd have the option of barely detectable scaling (at comfy couch distances) with the plus of easily detectable improvements in texture filtering and frame rate (and possibly other stuff too, like a reduction in nasty tearing). Overscanners probably wouldn't even be able to tell at all ...

 

[HTupolev]

Then you'd stick to the vertical resolution and scale horizontally at scanout, like consoles always did (MD / SNES / PC Engine / Saturn / N64 all had different horizontal resolution modes, and always looked "boss" on a CRT). I still have my Megadrive and RGB cable - unfortunately I had to bin all my CRTs....

Those modes usually used integer-multiple nearest neighbor, mostly because it was mathematically simple... it also just happened to avoid sample alignment issues in scaling. Applying the same logic to PS4, our options would be stuff like 1920x1080, 960x1080, 640x1080, etc.

Although what's interesting is that in the old days, the horizontal line signals were analog, so it would have technically been possible to "stretch" any image horizontally by any factor "without scaling it". With a fixed-grid signal, that's not an option.

 

[function]

Yes, that's what I was getting at. There was no scaling as such, the scanout simply converted the colour across that element of the image to the appropriate period of the signal output. Horizontal scaling - or rather stretching - was automatic.

So the Megadrive's 256 and 320 pixel horizontal modes both appeared perfect. No scaling artefacts. Lovely!

4K should at least allow some better scaling options for 720/900/1080 content that more closely resemble the kind of effect you got with CRT. I guess that will be the real blessing of 4K, because pushing for 4K resolution natively won't be good even on next gen consoles.

 

[Cyan]

Not that many Full HD tvs still do this, especially if they have game mode? I haven't seen one in real life yet anyway.

Yes, that's pretty rare. Philips are my favourite TV manufacturer and their HDTVs always have a 1:1 pixel mapping option --normally called Unscaled. Same with Samsung -even for older models, like my 22" HD Ready TV from 2007.

With that in mind, I can say that I've "correctly" played all the games I have on my consoles, and while 1080p compared to 720p can make a slight difference -not that much but still noticeable if you are a techie- there is a thin line when it comes to other resolutions. -say Far Cry 4 style-

 

[mrcorbo]

Unless said CRTs were receiving the common 480/576/720/1080 resolution standards, which easily could have been how things turned out in a world where flat panels hadn't taken over.

I don't understand how that relates to what I said. To clarify and expand on my comment; While CRTs don't have a fixed resolution and therefore don't always require scaling of alternate resolutions like fixed pixel displays do, in order to avoid having to scale you would have to render and output to a supported resolution. Given that the next standard resolution below 1920X1080 is 1280X720 you would be making a big reduction in overall resolution in order to avoid scaling. So, not having fixed pixel displays wouldn't really make for less of an issue.

 

[mrcorbo]

For those worried about upscaling artifacts, just add an a/v receiver. Even cheap ones now come with very high quality upscaling options over hdmi...

You have to send them a resolution they support, though. Are you advocating sending out 720p and scaling that?