[Enhancement]: Compress Mii images

[jonbarrow]

Checked Existing

• I have checked the repository for duplicate issues.

What enhancement would you like to see?

After rendering the Mii images, they can be somewhat large. They can be compressed however to save quite a bit of space (according to @InternalLoss they can be taken down from ~10KB to ~4KB). This saves both storage costs and time when rendering many Mii's on platforms like Juxt

Any other details to share? (OPTIONAL)

Right now the PNG renders are just straight from Mii Studio, no added compression. Using something like Sharp we can set a zlib compression level to get things down

For TGAs we use https://www.npmjs.com/package/tga, which does support RLE compression for parsing but not for output. We have our own TGA implementation here https://github.com/PretendoNetwork/pictobox/blob/master/src/tga.ts, however it also does not support RLE compression for output. It might be worth considering adding RLE to pictobox and then also compression the TGAs?

[shutterbug2000]

It may be worth ensuring that the Wii U and 3DS support RLE for TGA images (iirc the TGA support on Wii U has quirks, but I could be mistaken)

[jonbarrow]

Good point, it does have weird quirks so it's possible it doesn't support RLE