1-1 pixel perfect screenshots

[menace]

I have been trying for a good bit to get as perfect screenshots as possible, and I have spent countless hours fiddling with the setup in order to get as close to "the real thing" as possible, but yet it seems I am missing the odd pixel/line. I can't for the life of me find out what I'm doing wrong, so I turn to the community to be laughed at and (hopefully) helped out.

I'm currently running WinUAE 2.3.0, but have been struggling with this problem forever, so it's not new. In the Display settings, I set Windowed to 360 by 284 (half what the normal Double Line mode uses), Line mode to Normal and Resolution to Hires (normal).

My results clearly do not have all the pixels in place;



Halp!

[Toni Wilen]

WB is hires (640+ pixels per line depending on overscan)

[menace]

Ah, so I was thinking all wrong - and demo screenshots SHOULD be 1-1 with this setup? What setup would I ideally use for Workbench screenshots?

[Steve]

Try 720x576 double line mode and high resolution.

This should fit all the display in the window at 1x1.

[TCD]

For workbench 640x512 is enough (no grey borders).

[Toni Wilen]

What do you mean by pixel perfect? Emulation screen is always "pixel perfect" (if no filters used).

Some pixels are duplicated, just like real Amiga monitor has 2 hires "pixels" in place of one lores pixel. (Few programs have both lores and hires pixels on same horizontal line that can strech your definition of pixel perfect )

[menace]

By "pixel perfect" I mean that if a game is running at 320x256, I want to output an exact 320x256 image file containing each and every pixel as presented on the original amiga, nothing more, nothing less

Just to be clear.

I am mostly looking to do screenshots from demos, the workbench things discussed earlier are very seldom the case. I just sometimes see minor details (most prominently, fonts) that seem "off", like they are missing one pixel size sideways, for example. I will experiment some more, and see if I can't give a few examples.

[AmigaFriend]

Originally Posted by menace

By "pixel perfect" I mean that if a game is running at 320x256, I want to output an exact 320x256 image file containing each and every pixel as presented on the original amiga, nothing more, nothing less

Just to be clear.

I am mostly looking to do screenshots from demos, the workbench things discussed earlier are very seldom the case. I just sometimes see minor details (most prominently, fonts) that seem "off", like they are missing one pixel size sideways, for example. I will experiment some more, and see if I can't give a few examples.

As Toni said on post #2 WB screns are 640 pixels width, if you use in image settings "Resolution: Lores" instead of "Resolution: Hires (normal)" you'll have truncated pixels, because you can't put 640 pixels on 320.


I you want to reproduce screenshot demos you'll have to cope also with overscan. The majority of demos use overscan that will pass way beyond the 320 pixel resolution.

[Maren]

Originally Posted by menace

By "pixel perfect" I mean that if a game is running at 320x256, I want to output an exact 320x256 image file containing each and every pixel as presented on the original amiga, nothing more, nothing less

Just to be clear.

If Toni could get something like "emulated monitor circuitry" implemented to deal with overscan, then I guess it would be possible, but again, I have never heard of such a thing and quite honestly I don't even know how exactly WinUAE outputs the graphics in comparison to what real Amiga hardware would.

Right now you get to choose a screen mode and WinUAE comes up with the centering on it's own, which may or may not look ok but it's far better than being through the pain of manually adjusting it yourself for every piece of software you run.

I've never heard of anything Amiga capable of handling a low-res, non-laced mode higher than 368x290, so IMO it would be the sensitive choice to build your custom screen modes around that.

[Toni Wilen]

Not possible. Overscan is different on different TVs and every user has different opinion which overscan is "correct" overscan.

[Maren]

In a highly hypothetical case, wouldn't it make more sense to just stick to the specs of the classic RGB monitor A1000's came bundled with?

[Toni Wilen]

Which came with width/height position and size adjustments..

[Maren]

Factory settings? well, obviously there's even more to this than I originally thought.

[Toni Wilen]

There is. For example old CRTs don't have exactly flat and square display area.

[Maren]

Yes, and that would probably require meticulous examination and measurement of the whole physical display at triad/scanline level, including what may be covered by the casing

[TCD]

Let it go Maren. You'll feel better afterwards

[Maren]

You're right, I just totally had to know a lil bit more about it before letting it rest, it's my recalcitrant nature, "won't happen, get off my back will ya" doesn't normally speak to me

[andreas]

Originally Posted by menace

By "pixel perfect" I mean that if a game is running at 320x256, I want to output an exact 320x256 image file containing each and every pixel as presented on the original amiga, nothing more, nothing less

Well, if you need explicitly low-res, what about trying on WB 1.3? (at least for the old demos)

It's possible to set WB 1.3 to *REAL* 320x200 / 320x256, even in WinUAE.
No pixel doubling and things like that.
I sometimes do that myself (windowed mode though), having Windows itself set to unusual 640x480 native resolution. But if you want to prevent screen gfx from getting "falsified" by scaling at all costs, there's not many other alternative ways to go.

WinUAE must be set to Normal for that in gfx settings (w/line-doubling off, of course, since you do not want a squeezed screen, do you?!)

However, it will get a fairly difficult task real soon-ish.
Because, if you intend to run formerly disk-based demos from WB, it's not the world's easiest thing to get a WHDload setup running on 1.3 (it can be done, but you need an ancient version; nor can you be sure that each demo will be compatible with the ancient WHDload build).

[NoX1911]

PAR16/15 to PAR1:1 (square) (wiki) is reference conversion if you keep standard amiga resolutions to a 4:3 aspect ratio. In short, you squeeze 5:4 (640x512) into 4:3 (CRT visible area). Todays visible 4:3 area is 640x480 so you have to rescale 640x512 to 640x480 for proper aspect ratio on todays square pixel output. Technically this isn't pixel exact any more.

(Trivia paragraph removed. Too confusing.)

[TCD]

This is about screenshots NoX1911 So just a setup without any filtering will produce at least screenshots that can easily be made '1-1 pixel perfect' by point resizing.