Weird GameCube 480p problems

[Konsolkongen]

This is hard to describe but I get this weird vertical blur on 480p on my GameCube. In some titles the problem doesn't show, in others it's always there, and in some games they can go away by quitting the game to menu.

PAL GameCube
original component cables
HDMI mod
Qoob Pro modchip

The following example is from Phantasy Star Online III with component cables. First image is the character select screen just after the game has booted. Second is when I quit the game to the menu, and then the image clears up (it looks perfect):
https://imgur.com/a/S9XEi80

This has also happened in F-Zero GX (although not at the moment for whatever reason) where I could just reset the console to fix it. Metal Gear Solid, Metroid Prime and Paper Mario are borderline unplayable. I cannot get rid of it. Both Metroid and Paper Mario looked great when I tried them some time ago.

What could possibly be causing this? Is it the Qoob chip or the HDMI mod even though it shows in component too? I do not remember seeing this issue prior to installing the HDMI mod, but then again the Qoob has it's own share of quirks so I wouldn't be surprised if this is caused by it.

I've tried all possible Qoob firmwares as well as all it's video settings. I have also tried booting from Swiss but some games doesn't load at all (Phantasy Star III).

[Extrems]

Uh, I'm pretty sure I fixed Phantasy Star Online Episode III: C.A.R.D. Revolution 7 months ago.

[Konsolkongen]

Sorry, forgot that I'm on an old version because I couldn't get iplboot to launch the newest. Good to know that it's working now

[6t8k]

Interesting issue.

So inferring from what you say, it happens with both YPbPr and HDMI output? Perhaps to isolate the cause a little bit, did you try a different TV/monitor, or an unmodified GameCube with the same games on the same display?

[Fudoh]

interesting indeed.

I also would have said it's the TV doing some kind of shenanigans. But this could only happen if the HDMI mod's output was chroma subsampled. If you get 4:4:4 then there's no way the TV begins interpolating the chroma channels on its own.

But given what we've seen on the Wii HDMI mod and the fact that the internal signal is 4:2:2 to start with, I would say it's the HDMI mod taking the raw signal and either choosing a bad type of chroma interpolation or is maybe locking onto the signal in the wrong phase. In any way, the HDMI mod is likely the culprit. The phase theory would also explain why it sometimes look good and sometimes it doesn't. All this said, it's usually something I would expect on the horizontal though, not on the vertical. You see the same effect with bad chroma upsampling causing outlines on vertical edges. Here you basically see outlines on horizontal edges as if the upscaler was shifting the YCr channel down by one line.

Is the HDMI mod outputting 480p to your TV or is it upscaling internally ?

[Unseen]

But given what we've seen on the Wii HDMI mod and the fact that the internal signal is 4:2:2 to start with, I would say it's the HDMI mod taking the raw signal and either choosing a bad type of chroma interpolation or is maybe locking onto the signal in the wrong phase.

But he wrote that it also happens with the original component cables, which still receive the original video data. If the HDMI mod is the cause, it can only because of increased load, crosstalk or an outright short on the video bus.

All this said, it's usually something I would expect on the horizontal though, not on the vertical.

Indeed, 4:2:2 only reduces chroma resolution in the horizontal direction.

You see the same effect with bad chroma upsampling causing outlines on vertical edges. Here you basically see outlines on horizontal edges as if the upscaler was shifting the YCr channel down by one line.

Actually the problem looks a bit like deinterlacing with swapped fields to me.

[Extrems]

Deflicker on


Deflicker off


It's a nothingburger. Use Swiss. Force 480p.

[6t8k]

Huh, alright then.

I just read this and this which was elucidative - takeaway: my former understanding was that in 480p, the deflicker filter is turned off automatically, but apparently, this does not apply in all cases (there's also a deflicker, or rather, "softening" filter for 480p), and with Swiss, you can force-disable it for both modes.

It's still strange that you were able to "toggle" it by quitting to the menu / resetting the console (maybe a side-effect of the Qoob Pro?), but if you always force-disable the filter in Swiss, you shouldn't need to worry about that anymore...

[Konsolkongen]

I didn't explain the blur right, it isn't just on the vertical axis, that was just easier to spot in the Phantasy Star shots.

My TV is properly calibrated (no sharpening added). Everything is linedoubled through the OSSC to 960p.

It's true that when I boot Phantasy Star III with Swiss the problem is immediately gone and the picture is as sharp as my second picture without having to exit to the menus first.

Paper Mario appears to be fixed when booting through Swiss. It looks like I remember it now.
https://imgur.com/a/rRk9fdH

On Metroid Prime the vertical blur appear fixed, but it's still blurry horizontally. I seem to remember that this looked much better when I played it through the OSSC years ago.

I see no improvement in Metal Gear Solid (just recently got this game, so my experience is limited), but is it really supposed to look this god awful? It appears there is some kind of super strong blur filter on the game

No improvement in Zelda Wind Waker. Is it really supposed to look this shitty? Notice the blur on the left and right side of the wooden pillar:
https://imgur.com/ipm49Jx

I would like to try these games on a GameCube with no GCvideo, but since I'm in Europe and I only buy US and JAP titles I would have to install at least a XenoGC in another console to boot them. Not ruling this out but unfortunately I don't have any chips handy atm.

I've tried these games on my WiiDual modded Wii too and they behave the same, i.e. much more blurry than I remember. Maybe I'm just remembering these games looking much better than they actually do? I remember them looking as crisp and sharp as a Dreamcast game, but instead they look like PS2 with all its blur features enabled :/

[Extrems]

The mentioned games use horizontal scaling. You can also force that off, but you'll need to compensate somewhere to get the correct aspect ratio back.

[Konsolkongen]

Thank you very much! Setting horizontal scale to 1:1 makes Metroid Prime and Metal Gear Solid look a million times better! My TV can compensate for the aspect ratio if necessary.

I guess I had just forgotten how these games actually looked. Weird about that F-Zero and Phantasy Star deflicker glitch, but it doesn't appear to happen with Swiss.

I like that Swiss can remember individual settings for disc games too. Makes it a lot easier to just setup and forget. But is there a way to quick boot a disc game without having to navigate to the disc directory? For example by holding down a button when Swiss is booting?