Reply To: Help Needed: Need some overlays to be tested

[patrickm]

[quote=97434]Excuse me if I wrote something that was not meant that way. I’m german and don’t always know the right wording. I did not want to upset you. ?

You’re right , on the hill , you can see very few emulated pixels that are a little less wide.
But you have really search for it and you notice it only if you know what to look .

Also in SNES Zelda the first dungeon.
But with smooth and my overlay, it falls on even less.

For you it’s necessary that every pixel look absolutely identical.
For me it’s necessary that the overall image simply looks good.
But that’s a matter of opinion, any way he likes.
Similarly the darkness of the scanlines, to me it looks to darken, no matter how I adjust the brightness.
With the sharpness of your image there looks to me to blocky.

You might also right about the high end TV, but i never played any console on a high end TV. Did you?
99,99% of all people only played on a consumer grade CRT with this “softness”.
All this is the reason why the overall image of a console like SNES, Genesis… looks more uniform and better on a CRT than on a LCD without filter or shaders ….to me ?
Sure, there exists better CRT shader as an overlay image, but the pi can’t handle these.

Actually it was originally indeed about why the whole picture is very dark with your overlay images, it’s because of your resolution settings and the resolution of your overlay image. ?

Sorry but neither with the sharp-bilinear shader nor with the pixelate shader
I see any difference, no matter what settings…?
Maybe you can post a picture on you see the differences?

I now have my original SNES connected and then I realized that I had totally forgotten about the PAL borders. ?
Thus, the aspect ratio at all is no longer correct (1.63) and the individual pixels are also wider to see it there.

More example pictures:
Example Images Dropbox

[/quote]

Don’t worry, you didn’t offend me, it’s just that this whole topic is very contentious and people have a tendency to argue about it for pages and pages :) don’t worry about your English, either- it’s certainly better than my German! This post is going to be long, so I apologize in advance :)

You say you have to really look for the warped pixels. This might be true if you are sitting far enough from the display/have a small display. The warped pixels look especially bad when objects are scrolling, but you might not notice this on a crappy LCD with a lot of motion blur (as most LCDs have). I have a tendency to really scrutinize images because I’m obsessed with picture quality. Once I see these things, I can’t unsee them, and they become a real distraction.

Most image purists/ videophiles will agree that scaling artifacts are the cardinal sin, to be avoided at all costs. This is because, aesthetically, it is worse to warp sections of an image by different amounts than it is to warp the entire image by one amount. But you’re right that this is not 100% objective.

As far as the image appearing too dark, it is probably a problem with your display if it hasn’t been properly calibrated. EDIT If you aren’t used to viewing a calibrated image, than it might appear too dark. Also, you might be forgetting how dim CRTs were. An LCD is more than bright enough to have 100% black scanlines (reducing the effective backlight by 50%) and still be brighter than a CRT was.

The way scanlines work is that the higher the contrast between the scanline and the “drawn” lines, the greater their effect. Scanlines work like a pointillist painting: at the right distance, the human visual system blends the image and it results in a smoother image than actually exists. This effect is achieved more easily when the “gaps” are more easily recognized as such. I’m fairly certain that this could be confirmed via psychological experiment, if it hasn’t been already.

Another thing to consider is that each improvement to CRT technology brought images that were sharper, brighter, and had darker scanlines. First you had regular shadow mask CRTs. Then dotmasks came which allowed more light to pass through and had a less noticeable mask. Then you had aperture grills, which allowed even more light to pass through and were even sharper, with an even less noticeable mask. Then you had the king of CRTs, the Sony BVM, which had an almost invisible aperture grill, 900 lines of horizontal resolution (close to today’s 1080p displays), and was even brighter and sharper. The result is those perfect scanlines that die-hards covet.

The overall point is that CRT quality has always varied very widely, so the graphic artists didn’t have a single use case that they could base their designs on. Sure, most people didn’t have BVMs, but a lot of people had Trinitrons, which were significantly brighter and sharper than standard shadow mask CRTs.

Another point is that trying to replicate the eccentricities of a CRT on an LCD is just hard to pull off without looking fake. The CRT shaders are computationally demanding and won’t run on the raspberry pi, and they require a lot of tweaking to look right IMO. Even then, they are going to add an amount of input lag dependent on your processor speed.

I guess I only like scanlines because they filter the image while still looking authentic to me. All the other effects look like an LCD trying to be a CRT and it feels inauthentic. The worst offender in this regard IMO is the screen curvature effect. I played on all kinds of TVs with curved tubes, and I never recall any curvature like what I’ve seen shaders do. This is because a curved CRT was calibrated so that the image looked square/flat when viewed from a normal angle. A lot of the CRT effects look like an artist’s interpretation of a CRT to me.

Now, back to the original topic (!) :)

You said the darkening problem with the overlay was due to the size, that’s also what I suspected, so thanks for confirming that.

I’m sorry, I neglected to mention that when you choose sharp-bilinear you need to set shader filter to “linear” for it to work. Pixellate won’t run on the pi because it is too demanding.

Yup, PAL games all had those black borders on all systems. This is because PAL TVs were better, having 576 horizontal lines of resolution vs. NTSC’s 480 lines (a 20% higher resolution). The console only puts out 240 lines so everything over 480 winds up as a black border.