I just came across this and it looks very promising:
Apparently @Juandiegous fine tuned the Blargg NTSC Filter to match a real Sega Genesis without producing the undesirable artifacts we have all come to expect from it!
Can this be tested to verify the improvements and integrated into the Mega Bezel Reflection Shader?
So this is a filter rather than a shader, I haven’t used filters much. I’m not sure if they are applied before or after the retroarch shader pipeline. If they are going to be applied after they aren’t going to be any use with the mega bezel. You should try them out and see what happens, I think also sometimes a core can use the filter directly.
Dunno - Shaders & Filters? - RetroArch / General - Libretro Forums
I just tried @Juandiegous’s custom filter and it works very well in conjunction with HSM Mega Bezel Reflection Shader! The results are better than the filters that are currently there in the Filters folder. It does the blending without being too excessive in the blur and distortion department.
Whoo hoo just hit 6000 downloads of this little package!
Big “surprise” incoming, hopefully tonight 
Fingers crossed and waiting with baited breath!
Mega Bezel is updated to V 0.9.090 2021-12-24
This is the first release candidate for the V1, We’ll get some usage from the community & do some bug fixes, then probably another RC then when things are super stable it will get submitted to the main repo as the V1.
Changes:
The Headlines:
BIG Changes to the preset levels,
Snapshot from the help in a markdown reader
Change Details:
HERE ARE THE LINKS!
INSTALLATION INSTRUCTIONS
Retroarch/shaders/shaders_slang/bezel/Mega_Bezel
Give it a Whirl and let us know what you think!!!
Edit, there was a syncing problem but the files should now be updated
Nice! @HyperspaceMadness!
I have a “bug” to report. When the cache graphics are on, my custom TV image is downsized until it’s gone, leaving only the bezel and reflections (and the game image inside).
This is the background, I’m running Retroarch in 4K. Cache off still works.
Also, can you increase the negative cropping to -15 or -20?
Ok, so does the graphics appear then kind of slide off the viewport?
This is due to having retroarch’s billinear filter on, if you turn this off it will go away .
I’ll try to fix this so we don’t get this interaction.
It’s sort of possible, but the 10% that’s there now is adds 20% to the core image as it goes through the pre-crt pipeline. To increase it to 20% would add 40% to the core image. The more that is added would slightly slow down the pre-crt processing.
Mega Bezel is updated to V 0.9.091 2021-12-24 Rel 2
Changes:
Happy Bezeling
Thank you @HyperspaceMadness!
I don’t know if this is a bug, but with this version of the shader when GTU is on, it seems a lot blurrier than before (V 0.9.090 2021-12-24 was fine).
It is probably some new guest setting, not the Mega Bezel. Does adjusting correct it?
I don’t it’s Guest’s because it was working fine before the last update. (0.9.091 2021-12-24 Rel 2) Adjusting makes it better (less blurry).
This seems like a side effect of expanding the image for more negative cropping, because now the game image is actually smaller within the surrounding black space before the crt shader is evaluated.
I can probably compensate in GTU so that we get the same effect as default GTU.
I also having problems loading BSNES core (Retroarch crashs) with the new update (0.9.091 2021-12-24 Rel 2), version before was fine (V 0.9.090 2021-12-24) maybe also related?
The masks also feels “less strong” with the new update, before I was able to see the mask effects better.
Observation: “The new update” I’m mentioning is the last version you posted, the version before (also new) was just fine.
Yeah this might be related to the larger image caused by the larger negative crop, I’m thinking I’m need to backrack on this change since it’s causing this kind of problem.
I’ll put up a new version soon where the cropping is back to what it was before
Mega Bezel is updated to V 0.9.092 2021-12-24 Rev 3
Changes:
I really hope this approach doesn’t have any negative side effects with respect to my shader presets because they rely extensively on fine tuning the GTU settings to get that final balanced look. Any compensation that is slightly off either way, will throw off the perfection.
@JHorbach1, is this feature something that’s absolutely necessary or just an added convenience?
It’s to simulate GBA Player (playing GBA games on a CRT with a border), but I don’t think this will be a problem since he rolled back the update causing the issue.
Are there any existing GBA Overlays that can already accomplish this? What about using Super Gameboy emulation?
There aren’t, Super Gameboy doesn’t emulate GBA games.
The whole negative crop was not my ideia, I just saw it in the patch notes and tried to use it to emulate a GBA Player border within a CRT background that I use (inside the bezel), but the 10% negative crop wasn’t sufficient to put the GBA game in the border perfectly, so I asked him if he could add more percentage, which he did, it caused the issues with GTU, he then turned it back to 10%.
If there’s no way to achieve more than 10% without causing bugs, I’m perfect fine with it.
