Thursday, March 29, 2012

Explaining Resolution and Aspect Ratio - The Intro of Castlevania Symphony of the Night

Castlevania: Symphony of the Night has seen three significant variations: the original PlayStation release, the Saturn port, and the PSP port, as part of The Dracula X Chronicles package. Today we'll be looking at the technical issues regarding display and resolution in each of these three versions. (We've talked about this before, so this is just a further elaboration on the subject, namely how it can go wrong when it comes to ports.)

First off, here are screenshots of all three, in the intro dialogue between Richter and Dracula, taken straight from emulators in the first two cases, and directly from the PSP in the last one.


PlayStation


Saturn


PlayStation Portable


The most significant thing to notice right off the bat is how much skinnier the PlayStation version is. (You can also see how the dialogue window is dithered in the Saturn version, rather than truly transparent, one of the many ways you can see how shoddily that port was programmed, but that's neither here nor there in this discussion.) It's skinnier because it runs in the PlayStation's low resolution mode. The PlayStation can output several resolutions - right here it's 256x240 (though it doesn't take up the whole display so it's more like 256x208), but it can run in 320x240, 512x240, and even 640x240. Some 3D games use the higher resolutions, and sometimes games even switch between resolutions, like title screens for example. Even Symphony of the Night runs its "prologue text" screen at a higher resolution. The idea is that since you can fit more pixels on the screen, the overall image has more detail.



Anyway, 256x240 is the lowest the system will allow. This is similar to the NES, SNES and PC Engine, which run at 256x240 or 256x224. However, standard definition televisions run at a 4:3 ratio, which means those dimensions don't quite match. 320x240 is proper 4:3, but SDTVs can scale the image appropriately to the proper proportion by adjusting the shape of the pixels, making them slightly oblong. That's why everything looks slightly skinnier in this screenshot than they would on a television - they're supposed to be about 20% wider.

Things get dicey when we get to the Saturn version:



The problem here is that the Saturn doesn't support 256x240 - the lowest resolution it allows is 320x240. So how do you fit a 256x240 image in a 320x240 resolution? Keep in mind that pixels, when rendered internally, are square - you cannot simply make them oblong like the TV does. Your options are (A) pillarbox the screen so it's black on both side edges, (B) reprogram the game to take advantage of the extra space, or (C) stretch the image to make it fit the whole horizontal screen. The Saturn versions opts to stretch the image, since pillarboxing would seem cheap, and as you can see, it looks terrible. (Though you can see where some extra pixels are displayed at the bottom of the image, so it does seem like there was some small attempt at expanding the viewing area.) You can easily pick out the pixel distortion pretty much everywhere, since some vertical lines are doubled, and others aren't. Granted, it doesn't look QUITE this bad on a television since the fuzzy display blurs things a bit, but it's still visibly worse than the PlayStation release.

Now, the PlayStation Portable version on Dracula X Chronicles:



There are two display sizes in the PSP version. We're going with the smaller one, since that one is closest to the original resolution. Due to the portable screen, the PSP can only run in one resolution: 480x272. By this point, most developers were confident that gamers knew the difference between standard 4:3 and widescreen, and would accept that games originally designed for a standard def TV would look awful fully stretched to the PSP resolution. (Didn't stop them from screwing up Valkyrie Profile or Final Fantasy Tactics, but that's a different issue.) So, pillar/letterboxing is generally seen as acceptable. However, it still doesn't run in 256x240 like the PlayStation version - instead, it's stretched to the same 320x240 resolution as the Saturn version. The difference is that the picture is filtered, something the Saturn couldn't do and counted on the TV to take care. This technique blurs the whole screen slightly but obscures the pixel distortion seen in the Saturn version. This was probably done to keep the proper ratio as you'd see on the TV, at the expense of image quality. (As illustrated in this post from two years ago, the PC Engine Dracula X emulation runs at 296x224, which doesn't keep the 4:3 ratio nor does it use the original 256x224 resolution it originally ran at, so neither is really correct, and looks blurry to boot.)

The only thing I haven't tried is the PlayStation version of Symphony of the Night running on the PSP. How does it display its pixels? Is it in the proper resolution or is it stretched like the Chronicles port? Again, all pixels are square on the PSP screen - they can't be made oblong.

Anyway, why didn't Symphony of the Night run in 320x240 originally? Technical issue, perhaps? It certainly would've avoided this issues down the road, but clearly they didn't plan for that.

On a related note, this article on the Doom Wikia explains a bit more about the ratio that Doom was developed for, and what we see rendered in screenshots now.

20 comments:

  1. As with all PSX games running on the PSP, you have several options - you can run the game at it's original resolution, but the image doesn't take up the whole screen. You can stretch it to fill up the whole screen, or maintain the aspect ratio. Either of the latter two options are filtered, so it doesn't look terrible.

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    1. Stupid Konami my eyes are not adjusting that well with the horrible port on the PSP! Holy crap why didn't they port it to either the PSN or Vita by now?? Absolutely Ridiculous! We are almost at the end of 2013 and still no port! Really sad! They instead ported the DS version of Mirrors Of Fate to the PSN and XBL! What??? Come on! I rather hear about Dracula -X in HD by now!

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  2. I emulated the PSX version on the PSP, and it wasn't much to write home about. The screen didn't stretch vertically to the edges of the screen (possibly due to the lowered resolution thing), so things were a bit hard to see, and parts of the HUD were cut off when trying to zoom in. The worst part was the awful ghosting that happened during movement. It wasn't distracting most of the time, but in levels with a lot of thin, vertical objects in the background, horizontal movement caused the entire screen to fade into some sort of transience.

    Also, what about the XBLA port of SoTN? I'm pretty sure that exists.

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  3. I found both the title and the article interesting, but I work in tech support for a software company that specializes in video and image capture, so scaling and aspect ratio are two of the struggles I often find myself explaining to customers who do not understand the effect changing dimensions can have no only on the overall appearance of the image, but the fine lines that can be made excessively jagged (when you scale down) or the muddy edges you can create (by scaling upward)

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  4. how do the psp versions look when output to a SD tv?

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  5. @Anon2, I only played the XBLA SotN as a demo when it came out, but I think you could resize and reshape the screen to pretty much every weirdass dimension that you wanted. Don't know what the default is though.

    @Anon2, dunno, I only have PSP2000 which only outputs to progressive scan, which means it only functions on my HDTV.

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  6. No wonder that English font always seemed familiar. I should have known this. :)

    http://i.imgur.com/EhZeZ.png

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  7. Is it just me, or does anyone else prefer the original localisation? I know the voice-acting gets criticism, but Blaustein's writing (I feel) is sharper in the original. The PSP port has too much verbiage and sound awkward.

    Interestingly, I'm pretty sure they only re-translated the dialogue but left the inventory lists. The Cube of Zoe item from the original PS1 release ended up in all subsequent English localisations.

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    1. HG101 posted an interview with Blaustein recently, and it turns out Cube of Zoe was named after his daughter. Perhaps they kept it in as a show respect for Blaustein?

      As for the localization, yeah, I think it's telling that Konami kept the original PS1 job when it got ported to 360. Really, the only voice that doesn't fit in the original is maybe Richter's; he sounds a little too old for his age, whereas the PSP version sounds like a good fit. But then you have issues like Alucard. I mean, good god, yeah Robert Belgrade's sounds unnaturally deep, but his voice does grow on you, especially towards the endgame.

      And then you hear Yuri Lowenthal in the PSP port, where he could not give a more bored and uninterested sounding performance.

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  8. the xbox version is exactly the same as the psn/ps1 title

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  9. I prefer the original localisation as well. I feel like the new one isn't really any better in terms of quality (it feels paraphrased from the original), and the old one has nostalgia working for me.

    I also hate Alucard's new voice actor. The old VA was cheesy but it worked well for the game.

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  10. @Sketcz, you're right, Blaustein took a lot of liberties with the inventory and enemy lists, which caused inconsistencies in later games, which were more faithful. But these were all kept for the PSP localization.

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  11. The Playstation is apparently extremely flexible regarding resolutions, if emulator output is any indication. Street Fighter Alpha 3 for example runs in 384x224. Lowest Saturn resolution is 320x224, though I have no idea why they implemented that mode, since there should be no difference between it and a 320x240 picture that leaves the additional lines just blank.

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  12. dorkly chair of the institute for space politicsApril 5, 2012 at 6:53 PM

    Are there any emulators that output stuff at the native resolutions?

    I vaguely remember Bleem! running KoF97's gallery mode at some fairly high resolution...

    And I think Thunder Force V had its menus higher res than the wallpapers on the disc.

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  13. I was truly disappointed when I couldn't change to the real resolution on the PSP version. I just didn't converted my own PS1 copy because I heard there was a new translation (which is true), the old familiars were restored (it's true too) and there's a new Maria mode (which, again, it's true). There are new English voices but having Yuri Lowenthal voicing Alucard is just too atrocious to keep them.

    Even through the new translation and features are quite welcome, the forced resolution with bad blur was awful, they should had just let the old one untouched instead

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  14. Interesting post.
    Just for speculation's sake and totally talking out of my *** here, but I can think of two possible reasons for rendering at the lowest possible resolution
    1- Having to draw less sprites on a smaller screen therefore obviously avoiding some slowdown, which is exactly what the SNES did. Specially useful for the Legion boss fight.
    2- And I'm really just speculating, but maybe it had something to do with frame buffer screen effects that SotN loved using during spells and such.

    Here's a movie showing off what a spell should look like at 0:50
    http://www.youtube.com/watch?v=Hykl3EGKJnc
    You have to set set all sliders on EPSXE on max to get that effect or else you'll just see a black box and glitches.

    I'm not too tech savvy but the way I understand how this works is, the game literally takes a screenshot of the screen and renders it as a texture, which allows them do all kinds of distortions and tricks with it, they even use it for motion blurring, psychedelic transparency on sprites, water ripples, etc.

    There's one simple use of this right at the beginning of the game, after you kill Dracula and the background crumbles away, the screen will turn into a sephia colored photo, rotate away and burn into ashes. Anyone who played it knows what I mean. The game over screen also melts down like that.
    Pretty much the same way Square did the battle transitions in FFVII.

    So having a smaller resolution might make sense for abusing the frame buffer?
    Also bear in mind the PS had half as much VRAM than the Saturn, so they couldn't just save a full 320x240 screen to VRAM like the Saturn could. Also one of the complaints about the Saturn port of SotN is the abnormal amount of lag it had compared to the PS version, maybe a side effect of having a larger screen.

    Just my uninformed 2cc, if you actually know better about computer architecture feel free to correct me but please don't kill me. :)
    I'll just link this for reference
    http://en.wikipedia.org/wiki/Frame_buffer

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  15. It's true, the PSX version of the game (like most PSX games) used the lowest resolution to clean up the frame rate and allow more "sprites" onscreen. In fact, there are no "sprites" in the game. The PlayStation is incapable of rendering sprites, because it has no 2D VDP. What the developers did was use textured polygons, and developed a 3D engine to appear 2D. It's apparent in some areas, like the clouds at the top of the castle and especially the cathedral. That's also why the PSX version has effects like transparencies, while the poorly programmed Saturn port only has semi-translucency in a few areas and dithering in most areas that call for transparency. The Saturn's 3D VDP is incapable of hardware transparency, but the 2D VDP can do it no problem. Rather than reprogram the game to use the 2D VDP, whoever Konami hired to do it dithered the transparent "sprites" (textured quads) and called it a day. They also just stretched the same PSX textures over the bigger polys at a higher resolution, which is why they look so pixelated and assy.

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  16. How about this improvement?
    https://s5.postimg.org/3vdodidcj/01-1.png
    https://s5.postimg.org/k929aeivn/01-2.png

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    Replies
    1. I just downloaded your resolution hack from romhacking.net. Awesome job, thanks for uploading it!

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  17. Your screenshots are broken. Have you deleted them from the source by any chance?

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