Which port are you using? The default option on PC is unfiltered.

I'm using the Wii port of mGBA.
I haven't tried the 3DS one yet so I'm unaware if that one has the default filter too.

The reason filtering isn't optional on the Wii port is due to not knowing exact pixel sizing of the screen, but I haven't actually tried to fix that yet. I'll look into that soon.

Thank you SO much for taking my request into consideration. :)

240p mode would be a cool feature too. 240p looks so much better then playing GBA games in 480p.

Added in 6a4af38.

I would also appreciate a true 240p mode for mGBA Wii. Setting it to unfiltered and pixel-accurate is still 480i.

I would love to do this if I have a TV or capture card that supports 240p. I'm not sure if I do, though. My old TV and my Blackmagic do not, but I haven't tested my new TV, or my Empia or Hauppauge capture devices yet.

@nateify You sure it's not in 480i? I also use unfiltered and pixel-accurate, but in 480p, and it actually looks super nice.

I can't view 480p on my CRT. However, Extrems fork emGBA supports 240p when the meta.xml is passed the argument "--scan-mode=non-interlaced".

VBA GX fork also supports 240p for GB/GBA: https://github.com/libertyernie/vba-wii