Upscaling of assets

We had a discussion in chat, I want to put that in an issue for later.

Basically someone on reddit was using some algorithms to upscale AoE2 assets.

See here:

He was using this tutorial with Python.

The idea was then, to use an upscaling algorithm in the assets converter or live in-game.

@TheJJ was proposing xBRZ for in-game use, which is really nice.

Another parallel option would be to use ESRGAN/SFTGAN for upscaling inside the assets converter. Because we don't want to require CUDA, we could change a config value from
device = torch.device(‘cuda’)“ -> “ device = torch.device(‘cpu’).

I would propose that we ask the user for the upscaling algorithm and the quality like 0 (copy - fastest), 1 (copy & xbrz/in-game - faster), 2 (esrgan/sftgan-cuda, fast), 3 (esrgan/sftgan-cpu, slow). For CUDA we could just test and give an infobox to manually install CUDA if wanted (option 2 greyd out) and run the converter again afterwards (conversion stopped) or go for option 3 instead. Nevertheless, we would require pytorch then, if not already required elsewhere.

No source file or test is named. Start by locating the assets converter and the in-game asset-rendering entry point, then review the proposed xBRZ and ESRGAN/SFTGAN approaches. Done requires a settled scope for algorithm and quality selection, CUDA handling, CPU fallback, and dependency requirements.