Sony Megatron Colour Video Monitor

Let’s just put it down, 3 pixels of white on a RGBW display:

XBBGGRR:
xxxxxxBxxxBxxGxxxGxxRxxxRxxxxxxxxxBxxxBxxGxxxGxxRxxxRxxxxxxxxxBxxxBxxGxxxGxxRxxxRxxx

BBGGRR:
xxBxxxBxxGxxxGxxRxxxRxxxxxBxxxBxxGxxxGxxRxxxRxxxxxBxxxBxxGxxxGxxRxxxRxxx

RRGGBBX:
RxxxRxxxxGxxxGxxxxBxxxBxxxxxRxxxRxxxxGxxxGxxxxBxxxBxxxxxRxxxRxxxxGxxxGxxxxBxxxBxxxxx

RRGGBB:
RxxxRxxxxGxxxGxxxxBxxxBxRxxxRxxxxGxxxGxxxxBxxxBxRxxxRxxxxGxxxGxxxxBxxxBx
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RRGGBBX looks to be the most evenly spaced to me but I’m sure you can argue that. Certainly I don’t know how the reversed options are giving a better image - unless the OLED display is actually a BGRW?

EDIT: I suppose BBGGRR is reasonably evenly spaced - mathematically not as evenly spaced as RRGGBBX but not sure if you would be able to tell the difference with the naked eye.

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I thought the WOLEDs were RWGB but according to this https://www.rtings.com/tv/tests/picture-quality/pixels they kind of look like GRWB, but I’m not sure how to actually tell.

Off-topic but I really want to see you guys mess around with that triangle QD-OLED layout. That seems a lot more fun than finding out where/why/how the white subpixel is screwing things up.

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Thanks! Ok so they’re WBGR i.e reversed RGBW which now explains why we’re seeing the reverse patterns look better. I’ll update the above patterns and see where we get to but I’m guessing it’ll be XBBGGRR is best then RRGGBB as that’s the opposite layouts of the results above.

EDIT: I’ll stick with RTings image of starting with Red i.e RWBG but it shouldnt make any difference to the spacing as it’s just starting in the reversed pattern in a different position.

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The white subpixel isn’t screwing anything up. Where’s the evidence of that? That’s an assumption based on theory.

I think we’ve moved past that now. It could just be that we need to find a mask that fits the OLED Subpixel colour order because it doesn’t seem to work well with “standard” subpixel layouts i.e. what we’ve seen before in LCD panels which were either RGB or BGR. There are even LCD panels with White subpixels and other “new” non-standard layouts.

Look at these pictures here. Where do you see the white subpixel screwing anything up?

Here is the output of CRT-Guest-Advanced for comparison and reference purposes.

CRT-Guest-Advanced - Slot Mask - BGR Layout

CRT-Guest-Advanced - Aperture Grill - BGR Layout

20220810_185249

CRT-Guest-Advanced - Aperture Grill - BGR Layout

This is what I would call progress.

Even if there were two masks that work well enough with OLED Subpixel Layout to produce even “phosphor” triads in Slot Mask and Aperture Grill Presets I would say that’s a step in the right direction.

Samsung’s QD-OLED implementation obviously didn’t consider this use case. Maybe it might make a good Shadow Mask someday but let’s focus on solving 10 year old WOLED first as it has proven and established itself in the market and there have been recent breakthroughs in suitable CRT Shader Preset development which address their particular design.

I’m merely trying to assist in expanding that and continuing this development. Pretty soon this might actually be behind us but don’t be distracted by this white subpixel. Nothing I’ve viewed on an OLED TV looks like those RTINGS subpixel macro pics. I’m not saying that they’re inaccurate, I’m just saying that LG’s algorithm does its thing silently and seamlessly and it does it well.

But this thread is about Sony Megatron Color Video Monitor and I have a feeling it’s going to get even more awesome pretty soon!

@MajorPainTheCactus,

Couldn’t it be as simple as just using RRBBGGX or XRRBBGG for Slot Mask and BBGGRRX or XBBGGRR for Aperture Grill?

Can you possibly add those experimental Mask Layouts and some of us OLED users can test them and see if they work better than what is there now and report our findings?

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Looking at line 204 in crt-sony-megatron.slang:

#define kBBGGRRX { kBlue, kBlue, kGreen, kGreen, kRed, kRed, kBlack }

BBGGRRX is already present and accounted for as the 300 TVL BGR layout mask. XBBGGRR should be possible by changing that same line to the following:

#define kXBBGGRR { kBlack, kBlue, kBlue, kGreen, kGreen, kRed, kRed }

As well as line 210:

{ kRRGGBBX, kXBBGGRR }, // 300 TVL

This can even be done in real time. Just load the shader as usual, set the mask type, then open up crt-sony-megatron.slang in a text editor, change the line, save the changes, then in RetroArch, go to the Shaders menu and click on Apply Changes, and it’ll, well, apply the change you just made to the shader file.

This is purely for the aperture grille layout, mind you. The slot mask layout is a bit more involved, but the relevant lines are 320, 335 and 342.

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Thank you very much. This might very well be the way! It should be possible to at least get Aperture Grill to look like my picture and then Slot Mask can probably be attempted next.

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It’s always done this. In fact it was possibly the first to do this if not for aperture grille then definitely for the slot mask. Have a look at the code and see. This mask produces a 300TVL simulation on a 4K monitor just select 300TVL.

If you have any complaints post close up shots of the problems you are seeing - not of other shaders obviously.

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It’s even easier than that - in the TVL settings of the shaders parameters just set it to 300TVL from the default 600TVL under the TVL settings. No need to edit any files!

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It’s not quite the way as it’s easier than that but @GPDP1 is completely right on the rest.

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The 300 TVL mask is BBGGRRX. @Cyber was asking if XBBGGRR (that is, with black first rather than last) was possible, and I surmised it was by editing the mask. I don’t know that it would make a difference, but I supposed if he wanted to try it out, that’s how you’d do it.

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There’s no difference between the two to all intents and purposes - one is just offset by a pixel to the other. You’d never notice this in reality.

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Yeah, that’s what I thought as well. Only reason I even entertained the thought is because we’re dealing with OLED weirdness here, and it seems like we’re kind of throwing things at the wall to see what sticks lol.

Anyway, @Cyber ought to easily be able to manipulate the mask now and try out various subpixel arrangements.

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We’d never notice it but perhaps it might make still better fit the OLED TV’s layout better for these purposes.

I was also asking about RRBBGGX or XRRBBGG because that’s what worked with the Slot Mask “phosphor” triad in the example.

But no need to stress or lose any sleep over this. I will go digging around sometime using my trial and error and observation methods and see what happens on the output side as I alter the colour order and shift around the subpixels.

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It’s got nothing to do with the OLEDs sub pixel layout this difference is at the pixel level not the sub-pixel level (which is where OLEDs differ from LCDs).

Imagine you display a full screen image on one monitor and then display the same full screen image on another monitor but offset it to the left or right by a single pixel. Nobody would be able to tell the difference between the two images because they are identical. This is what we’re saying here.

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Sony Megatron Color Video Monitor, Aperture Grille - RRBBGGX

LG 55OLEDE6P

Any questions?

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So on an OLED, you feed it RRBBGGX, and it seems to output BBGGRRX instead?

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Or it could be outputting RRBBGGX just with a larger gap between Red and Blue and the real X not being seen properly because of the unique subpixel structure.

What’s most important is that we now have our three primary colours being displayed in an evenly spaced triad which we weren’t getting before on OLED TVs. The order is not as important. This should be an improvement for users of OLED TVs.

Please see what @nfp0 had to say about that when I asked myself the same question you asked. It’s in the post I shared.

Based on my testing so far, it only appears like that on Aperture Grill Masks. On Slot Masks it looks more like RBG as shown in my examples.

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That would be completely impossible. Here’s the post @Cyber is talking about:

What’s going on here - is that you editing the file to create a RRBBGGX mask? As it looks from the pictures like my standard XBBGGRR mask as in 300TVL at 4K using BGR layout.

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