[eatnumber1]

True zoom functionality is not possible on the OSSC, as it doesn’t have enough memory for a framebuffer.

The technique used in PSP mode on the OSSC leverages the television’s framebuffer, so doesn’t work on a CRT.

What you’re asking for will only be possible on the OSSC pro.

[eatnumber1]

Handled in https://videogameperfection.com/forums/topic/psp-help-for-a-total-noob/. We hypothesized that their TV doesn’t support more than 203 offscreen lines.

[eatnumber1]

upsample2x doubles the rate at which the analog signal is sampled. Essentially, you get “inbetween” pixels representing the analog signal at the point between two pixels. It has the effect of softening the image, which can look good for some e.g. 3d games.

I think it’s disabled for all optimized modes however, so changing it probably does nothing when the PSP mode is enabled. If your screen doesn’t flicker when toggling it, it’s doing nothing.

And could messing with the sampling and lpf thing help me get the 480×272 mode working? I have no idea what either option does.

Unlikely. If my theory about your TV only supporting 203 offscreen lines is correct, then it won’t help. Having those set wrong however can make your image blurry, hence why I thought of it when you said the image was somewhat blurry. The correct values for that depend on console, cables, ambient RF noise in your room, etc., so I can’t say what yours should be… I can only say what I do for my setup.

[eatnumber1]

Correction: OSSC Pro can fix this in theory. I have no idea if marqs is implementing it in such a way that it will work out of the box. It may require a custom mode be added.

[eatnumber1]

Sorry, I meant Analog Sync LPF (that’s what I get for replying on my phone).

I realized I did the math wrong for calculating which of the options fill the screen the most.

Option 1 is a 480×272 picture in a 576×324 frame. That’s 83% full both horizontally and vertically.
Option 2 is a 960×544 picture in a 1536×864 frame. That’s 62% full both horizontally and vertically.

So yeah, it makes sense that option 1 is larger then. If your TV has zoom / fill functionality, then as you’ve mentioned, use that with line2x.

Oh one more thought, make sure that upsample2x is turned off (I think it’s always disabled with PSP mode enabled, but I forget now).

As far as OSSC Pro goes, the fundamental issue that we’re running into is that we can’t change the clock rate of the video signal. We’re playing tricks with what’s onscreen vs. off, but the clock is always 858 pixels per line * 525 lines per frame * 59.94 frames per second = 26.9 MHz (or *4 in line2x, so 107.9 MHz). With the OSSC Pro, we’ll have the flexibility to read the signal into a frame buffer and output it at a much slower clock rate (without adding lag), which would have the result of removing the large offscreen regions, which will fix your problem. So yes, OSSC Pro will fix this.

[eatnumber1]

I made a few edits to my last reply. Can you check that you’re using the settings from my most recent edits? Sorry for the trouble.

If so, I’m surprised that option 1 fills the screen more. Nevertheless, we’re pushing up against a hard limit of 203 offscreen lines, so if filling the screen as much as possible is your priority, then there’s not much else to be done as far as the resolution goes as long as you also want to preserve the correct aspect ratio.

Also make sure you’ve got the Video LPF and Sampling LPF settings right, and your sampling phase set right. I turn both LPFs off, and tweak the sampling phase until the image is stable.

[eatnumber1]

Whoops, did those first two options’ aspect ratios incorrectly. I calculated against the 720×480 (4:3) resolution, when the TV’s aspect ratio is actually 16:9. Redoing that math.

1. line1x – 576×324
2. line2x – 768×432
3. line1x integer multiple to 4k – 640×360
4. line2x integer multiple to 4k – still impossible

With that aspect ratio, line2x (option 2) is actually going to be the most zoomed in because there’s 1.77x more pixels in the overall frame but 4x more active pixels. So line2x may be your best choice overall.

So in line2x mode, that’s
V. Active 432
H. Active 768

[eatnumber1]

Sorry, ignore the part about setting V. Refresh. That’s automatically detected by the OSSC.

In line1x mode with a V. Active of 322, there’s (525-322=) 203 lines offscreen.
In line2x mode with a V. Active of 424, there’s ((525-424)*2=) 202 lines offscreen. Because this is line2x, we can’t test with exactly 203 lines offscreen.

It sounds like your TV supports a maximum of 203 lines offscreen.

Building on that, in line1x mode if we can’t go below 322, then the aspect-ratio-preserving setting you should use for H. Active is (720/480=x/322; x=) 483, which is a resolution of 483×322. For line2x, we can’t go below 424, so that puts the H. Active at (720/480=x/424; x=) 636, which is (636*2×424*2=) 1272×848. Of those two (line1x and line2x), 1272×848 is ((1272*848)/(483*322)=) 6.9x more pixels than 483×322, while the actual image is only 4x more pixels (2x in both dimensions), meaning that line1x should produce the most “zoomed in” picture, but it’s probably going to be less sharp than line2x because your TV is doing more of the upscaling.

Also, neither of these resolutions divide well into 3840×2160 (4k). So let’s figure out what the nearest resolutions are that let the TV integer multiply up to fit the screen.

For line1x, the next nearest integer above 322 which when multiplied by a whole integer produces 2160 is (2160/6=) 360, and preserving the aspect ratio that’s (3840/6=) 640. That’s a 640×360 resolution, and you can get that by setting H. Active to 640 and V. Active to 360.
For line2x, the next nearest integer above (424*2=) 848 which when multiplied by a whole integer produces 2160 is (2160/2=) 1080, and preserving the aspect ratio that’s (3840/2=) 1920. That’s a 1920×1080 resolution (aka 1080p). Unfortunately, line2x does not produce enough total lines or pixels to get to 1080p, neither horizontally nor vertically. Including all of the offscreen signaling (some of which is actually needed), line2x is 1716×1050. So an integer division of 4k in line2x mode isn’t possible for you.

So your options are:
1. Most zoomed in – 483×322
2. Most sharp(?) – 1272×848
3. Even multiplier to get to 4k (might be more sharp than option 2) – 640×360

[eatnumber1]

You’re not out of luck quite yet, we’ve just got to put back some of the letterbox.

Start by using the advanced settings to restore the originally intended image — letterbox and everything. Make sure you’re doing this with the PSP sampling mode enabled and with line2x turned on (although if it doesn’t work, try with line2x turned off). Here’s how you do that:

H. Refresh 858
H. Active 720
H. Sync 62
H. Backporch 60
V. Refresh 525
V. Active 480
V. Sync 6
V. Backporch 9

In passthrough mode, this should give you the originally intended letterboxed 480p image. In line2x, it’s 1440×960, in passthrough it’s 720×480.

Now start to remove the letterbox by decreasing H/V Active. If your TV doesn’t drop sync, you’ll see the image growing larger, but also moving away from center of the screen. To re-center it, increase H/V Backporch until centered. Keep decreasing it until your TV loses sync. Whatever value you end up with (as defined by HxV) is the minimum resolution (aka most zoomed in) that your TV can support given the PSP’s true 858×525 input resolution (but see the next paragraph).

It’s also possible (likely, in fact) that your TV supports discrete resolutions around standardized values (e.g. 480p, 720p, etc.), but not the weird ones in between. So there’s one more resolution to try, you can cut the line2x 1440×960 image down to a 720p image. The 16:9 720p resolution is 1280×720, so to get that, get back to the default settings for the PSP I mentioned above, make sure you’re in line2x, and use the following:

H. Active 640
V. Active 360
Adjust H/V. Backporch to re-center

[eatnumber1]

What kind of TV do you have? Have you tried with both passthrough and line2x mode?

You should also try cutting off the top+bottom pixel from the image in line2x to produce a standard 540p resolution. The default (in line2x) is 960×544, which is non-standard and some TVs may not like (passthrough mode of 480×272 is also non-standard). This wiki article covers how to do this, but tl; dr: with the PSP mode enabled and set to line2x, in the advanced settings change

V. Active 270
V. Backporch 135

Also if you have a different source for a 540p image, you should test your TV with that source to see if your TV supports 540p at all.

If that doesn’t fix it, and your TV does support “normal” 540p signals, then it’s possible that your TV doesn’t like the very large offscreen regions of the image (much larger than usual), which isn’t something that can be fixed with the OSSC.

[eatnumber1]

Did you try adjusting the phase? The screenshots do look like it’s a bit out of phase.

[eatnumber1]

Back before I modded my wii I had done similar amounts of work, but sadly I didn’t take any screenshots. Hopefully someone else with an unmodded wii can chime in.

[eatnumber1]

Have a read through https://www.retrorgb.com/wii.html

The wii has poor video quality to begin with. You need to bypass it (e.g. with a wiidual) to get perfect output.

[eatnumber1]

Looks like jailbars
https://shmups.system11.org/viewtopic.php?f=6&t=62631

Also have a look through the google results for “SNES jailbars” to get more info.

[eatnumber1]

Sadly no, or at least it’s not straightforward. There’s no resolution switch as far as the OSSC (or your TV) is concerned.

However that said, I improved on this further since my last post, and 0.86 now has a dedicated sampling mode and an optimized line2x mode. So all you need to do is set “480p in sampler” to “PSP 480×272”.

It might be possible to count the size of the overscan area plus the letterbox and switch when the active region changes, but I’m not sure if that will be prone to false triggering in other places though.

Also FYI I looked into line4x. It’s not possible at all, ever on the OSSC (maybe the pro, idk). The HDMI transmitter cannot run at a fast enough clock speed. That said, I did some work to get the OSSC working better at clock speeds close to its theoretical max so that I can do line3x with a 3x vertical and 2x horizontal pixel clock (3x horizontal is also too fast). That work also got released with 0.86, although the Line3x mode is disabled because it’s not aspect ratio preserving. With those settings, it’s at the edge of what the OSSC can support, but it now works. With 2x horizontal, there’s enough room in the overscan area now that I can theoretically get to 3x horizontal without increasing clock speed by drawing into the overscan. The OSSC doesn’t support that kind of drawing mode yet though, so implementing that support is my next project. Once it works the output resolution should be 1440×816.

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