[4K Downsampling Experiments]

[[AlexanderTheNine]]

[So, downsampling is a hot topic these days in PC gaming. If you are not familiar with the term, it's when you render a game at a higher resolution than your display's native resolution, and then downscale it to fit your display. The result is said to produce a much greater-looking image. Since I have a 1080p monitor and 4K is all the rave lately [as it should be] I decided to do some downsampling tests on PCSX2, to see if I could produce an image that was truly better. If you want to know the results, read on

I set my resolution for PCSX2 to 3840x2160 [4K resolution], and fired the game up. It definitely looked better to my naked eye, but I really wanted to keep appearances out of it. You know, try to rule out the placebo effect. As a result, I took screenshots of FF XII at both 1080p and 4K. I have uploaded the results, for your convenience, to let you decide for yourself just how much better it is, or how worth it you feel it should be. To me, the difference was incredible. I zoomed in on each picture, and I implore you to do the same. Spots in the picture worth noting are the various badges/equipment hanging off Vaan's belt, the wooden crate the one creature is carrying [the creature's face has a lot of cracks and textures that are also worth zooming in on], and especially worth checking is the duck-like creature in the lower-left corner. Zoom in on his eye, and you'll see a great amount for comparison between 1080p and 4K. [Yeah yeah, or you could zoom in on the weird pirate lady's thong. Don't think I didn't see you doing it...perverts]

Now, bear in mind that this takes some serious GPU horsepower. I have a GTX 660, which runs for about 200 dollars these days. This card will run virtually any PS2 game on PCSX2 in 1080p resolution at 60 frames with no problem. However, using the card to run games at 4K significantly reduces the framerate. On FF XII, the game you see in my screenshots, it ran at a reasonable 40-45 frames a second for me...until I would go into my menu, at which point it would plummet dramatically. Also, enabling too many post-processing/upscaling effects, such as MSAA, or my external GSDx plugin, would completely tank the card, even outside the menu.

This is a call to arms! Anyone out there with some really powerful GPU hardware, such as SLI configurations or simply a better card than me [like a 780/980, or 290X if you're into that sort of thing], I implore you to continue where I've left off, if you've the time and interest. Try out various games, show us some screenies. Which games are worth 4K downsampling? Which cards can handle most PS2 games at such a high resolution with post processing and upscaling? The latter question, I am very curious to know. Screenshots below. Post your thoughts below!]
-Nine


Image 1, 1080p *with* post processing enabled
http://i.imgur.com/uwnV0U5.jpg

Image 2, 4K [3480x2160] *with* post processing enabled
http://i.imgur.com/aGOeGed.jpg

Image 3, 3X resolution preset, with post processing enabled, MSAA 8x as well [This is in its original format of 4:3]
http://i.imgur.com/pizN4sW.jpg

[Blyss Sarania]

For what it's worth, we generally feel that the supersampling effect from running at huge resolutions(with PCSX2) is pretty minimal(of course that's only our opinion). And running at 6x(which is basically 4k) is a GPU killer. Keep also in mind that increasing resolution increases CPU work as well(because the GS emulation itself runs on CPU).

Generally I personally suggest to use no higher than 4x, and to use MSAA in HW hacks. Looks just as good to my eyes, easier on the CPU/GPU. Of course that breaks a few games(notably Persona games), and in those cases I just use the highest res I can support(usually 5x, CPU limited) without slowdown.

Still, it will be good to see a comparison.

If you would, please also upload a 3x + 8x MSAA shot, for comparison of that as well.

[[AlexanderTheNine]]

[My hardware is strong enough to handle any CPU stress, but you have a point; I should have mentioned that. I honestly found a huge difference between 4K and 1080p. I also don't like running the preset multiples; I like to know my exact resolution and have extreme control over the emulation. If I'm not mistaken, PS2 games can run at different resolutions depending on the game [and the region it hails from], so I guess it's just me being finicky? Plus, I like to have a widescreen resolution in place, though it does little good without a widescreen hack to compliment it.

As far as your request - Right away! I am more than happy to oblige. Check back in a few minutes, and you should have your requested image up]

[Blyss Sarania]

Yeah. Well, PCSX2 is weird in that way in that, while for instance I think PC games look extremely good downsampled from 4k, it doesn't work as well with PCSX2. It may be the type of downscaling GSdx does, IDK.

For what it's worth, GSdx is slightly more compatible when using Yx resolutions than using direct set ones like 1920x1080. Most times no difference, but a few times it will cause glitches. Also in a very few cases, it's the reverse, where you have to use a direct resolution to avoid glitches(e.g. like in Soul Calibur III, where all upscaled resolutions result in lines on the screen, except ones that are 1200xYYYY manual set)

Anyway, yeah, like I said, that's just my opinion. The reason I wanted to say that is we get a lot of people with medium powerful machines coming in here wondering why PCSX2 is slow, and they are running at 6x. Most people don't know just how big 6x resolution is. For an average PS2 game running at 640x448, 6x is 3840x2688(e.g. slightly greater than 4k)

And you are right, different PS2 games run at different resolutions, and so Yx resolutions are slightly different depending on the game.

[[AlexanderTheNine]]

[New image, as requested. Apologies for the delay. This is 3x resolution with 8x MSAA. Keep in mind, the previous ones did not have MSAA enabled through hardware hacks; they were set to 0 MSAA. Also, the previous screens had special post processing enabled. To keep it fair, this new screenshot has the same post processing effects enabled, on top of the MSAA x8]

http://i.imgur.com/pizN4sW.jpg

[Blyss Sarania]

How come that one is 4:3 when the others are 16:9?

[[AlexanderTheNine]]

How come that one is 4:3 when the others are 16:9?

[Because it is 3X the resolution of the native PS2 resolution. While it does not look that way while playing it, since the emulator stretches it for me, the screencaps are taken in the native resolution without any stretching. I can take the image and re-scale it if you like, but that's taking away from it's true resolution. The image you see is what the image looks like before the emulator stretches it to the screensize, so in a way, you are seeing it in the best, most pure form I can offer. Anyway, this is one of the reasons I like to input custom resolutions - I can have the game render it at a widescreen format, instead of it rendering the game at a fullscreen format and then stretching it]

[Blyss Sarania]

Oh, you are using the internal screen capture tool then. I see.

[[AlexanderTheNine]]

[Yeah, I'm not terribly savvy with some things. I am but a lowly PC technician. It is indeed common for people to ask why their games run slow. I think that is a universal issue with all emulators. A lot of people do not understand that to *emulate* hardware requires hardware ten times stronger [or more] than the original hardware one is trying to emulate. The Nintendo 64 had 4 MB of Rambus RAM; 8 MB with the Expansion Pak. Trying to emulate that with only 32 MB of video ram [the amount of ram a PlayStation 2 has] is laughable, and will not yield any real fruit. Yet, when I emulate PS2 games without MSAA, I tend to use over 300 MB -more ram than the PS3 has! If the typical computer user could only understand this, I think a lot more people would be willing to upgrade their systems and get with the times. Not everything in the computing world is simple, least of all hardware emulation]

[Blyss Sarania]

Yes, you are very correct. We get people who even get ANGRY at us that PCSX2 won't run on their old hardware.

Even among emulation, PCSX2 is especially demanding due to having so many things to emulate - EE, GS, VU0, VU1, etc.

And it becomes further complicated because each game has different requirements. A comparatively weak machine can run Ar tonelico type games just fine in PCSX2. That same machine would find a game like Xenosaga unplayably slow. So we get questions like "Why is X slow, when Y isn't?"

And worst of all we get "But I can run Skyrim on medium! I should be able to emulate a lowly PS2 game. Obviously this emulator is *****"

or whatever.

It's hard to be patient, at times. lol