The AmigaVision team cares deeply about preserving the correct aspect ratio for all games. That means going beyond just ensuring that games run in the correct variant of NTSC and PAL, but we also ensure that the Pixel Aspect Ratio — aka. PAR — is correct. A pixel on the Amiga was close to square (16:15) in European PAL resolutions on a CRT, but quite tall on United States NTSC displays (5:6).
Most emulators and video captures seen online get this wrong and use 1:1 pixel aspect ratio for US NTSC games, so we built an implementation that handles the NTSC and PAL variants correctly, instead of what is commonly (and erroneously) the case.
Take a look at the difference using this screenshot from Defender of the Crown, which is a US NTSC game. All the character portraits are squished vertically when rendered in 1:1 pixel aspect ratio — what most people know as European PAL rendering on the Amiga — making the characters look shorter and more stocky:
In 2023, we completely reworked how this is handled, so you no longer have to manually switch to NTSC to get the correct pixel aspect ratio — which has tall pixels at a 5:6 PAR, as demonstrated here in Defender of the Crown.
All of these align to the 1080p/4K 16:9 pixel grid while having the correct Pixel Aspect Ratio, so you will not get any shimmering or non-integer pixels.