Gamecube 480p 2x mode aspect ratio not 4:3. Any ideas?

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Viewing 15 posts - 16 through 30 (of 32 total)
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  • #46226
    Yovan Basurto
    Participant

    My Swiss menu is in perfect 4:3 so that leads me to believe that it’s fine for me at 720 but when i pick games the aspect changes depending on the game. Just weird seeing Luigis Mansion in a 8:7 like aspect ration. Not as thin obviously but i get snes 8:7 vibes and i’m totally not used to it on the cube.

    #46227
    Harrumph
    Participant

    Here is the thread: Link

    I had misremembered, no GC game is actually as wide as 704px (it was the n64 zelda ports that were 704px).
    The gist of it is that a lot of games don’t use the proscribed 10:11 pixel aspect ratio (PAR), instead some use 32:33 (eg mario sunshine and luigis mansion), and some even 1:1 (square pixel). To achieve it on my TV, h.active needs to be changed to 704, 683, 660, or 640 (depending on game)!
    Luigis Mansion for example needs 660 h.active.

    Edit: btw the Swiss menu graphics were actually wrong AR for a long while, but i suppose they may have fixed that…

    #46235
    TrantaLocked
    Participant

    How is it possible some games have different pixel aspect ratios? Wouldn’t a CRT be processing the signal the same for all games, so it’s not like it would know to change sample rate depending on the game.

    For anyone doing Xbox stuff, you can use a few things to double check proportions. In THPS4 there is a stone sphere statue in San Francisco, and the circular map HUD in Halo 2. Both of these should measure as a perfect circle once you have it centered on screen. But just try to find something that you know is supposed to be perfectly square or circle in any game of your choice.

    #46243
    Harrumph
    Participant

    You are right, crt TVs couldnt tell these differences apart. My guess it’s down to oversight from the developers, not following specifications for whatever reason. Video signal specs are kind of a mess from the beginning… I presume noone really reacted before because overscan & geometry was variable between sets anyway, partially obscuring this issue.

    I don’t have an xbox, but I’m pretty sure the default samperate is not 780. IIRC you can set it to vesa 640×480, but then samplerate should be 800 (like the ossc 480p vesa input setting). I think in most scenarios, you’d want to set output to regular 480p and use the regular DTV matching sample rate: 858.
    If you reduced it to 780, you are undersampling the signal, which in itself distorts the AR. Also you cannot count the active output pixels properly, sampling needs to match output. If I were you, I’d stick with 858, and adjust AR by h.active instead, like I’m talking about in the above post/thread.

    #46247
    TrantaLocked
    Participant

    H. active only allows me to change how much of the picture I can see on screen. The only way to change aspect ratio is with sample rate, and I confirmed that 780 sample rate is correct for both THPS4 and Halo 2 using circles. With 858 the picture is obviously too wide.

    #46253
    Harrumph
    Participant

    Ah I see, yeah displays are unfortunately different in that way, on my TV it takes into account the active window and scales it to 4:3/16:9 (depending on mode). I have seen other posts in the past that some displays pretty much ignores active area and only pays attention to total width or some other factor. Which seems to be the case here… Too bad.

    #46254
    TrantaLocked
    Participant

    It still works out in upsample2x mode though. On a 1080p screen, the pixels available in a 4:3 space are 1440, while upsample2x for a base 780 h. sample rate gives 1560 output pixels.

    #46260
    Harrumph
    Participant

    Right, to output square pixels, PAR 10:11 applied to 858 = 780. It’s like 240p generic mode in x3 & x4, which uses multiple of 390.
    And you are correct, undersampling is not an issue when using upsamplex2. So maybe 780 h.samplerate is something to try for OP then (in 2x mode (960p) with upsample2x on). And if he wants to try the 32:33 PAR, 858 -> 832 h.samplerate.

    #46272
    Retrorunner
    Participant

    You are using swiss to force 480p? Have you tried a GC game which supports 480p natively (as an option)? My guess it might be a problem with swiss.

    #46273
    Yovan Basurto
    Participant

    It’s not Swiss. Been using Swiss for a long time and this never been a problem. Also I tried it without Swiss. It’s the ossc for sure.

    #46274
    Yovan Basurto
    Participant

    Lol. In English? No disrespect but man I don’t know what you said. I think I tried what you said but made no difference.

    #46276
    TrantaLocked
    Participant

    Harrumph’s thread said that some games like Luigi’s mansion were shipped with the wrong pixel aspect ratio and would even look wrong direct to a crt, but to counteract this either h active and or h sample rate should help resize the image. What exactly happens in screen when you change those settings?

    #46278
    Yovan Basurto
    Participant

    Nothing. Just moves the screen left or right but that’s it.

    #46279
    TrantaLocked
    Participant

    I wonder if there is a tag on the output EDID that the TV is latching onto. I mean if you set active area to something random like 1500×300 and h sample rate to something very low like 300, it’s still just resizing the image to the same aspect ratio as it would otherwise? If that’s happening the TV is definitely latching onto an identifier on the output like it thinks it knows better. It’s like if a TV saw “DTV” in the EDID and then proceeded to ignore literally everything else about the incoming data. Maybe if there’s a way to change a part of the output EDID on the OSSC to fix this, but that’s a firmware feature request.

    I went back and saw you mention it was sizing correctly over passthrough but not line2x. Do those settings also do nothing but move the picture for both as well?

    #48802
    Yovan Basurto
    Participant

    I think I figured it out! On Swiss I set the “force horizontal scale” to 720px. That made every game fill the screen at 4:3!!

    On some games like Luigi’s mansion it fills perfect. On others like sunshine and twilight princes I get some thin black bars on top and bottom.

    Is this due to the GameCubes different internal resolutions?

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