Improved memories of 4MP photos with upscaling

I found this discussion here:

So the question for me is, which is the best upscaler with gmic for my photos.

The screenshot was upscaled like this (4x):

gmic -i upscaler.jpg -fx_gcd_upscale_patch2x 2,0 -o gmic-upscaler.jpg

Do I understand it correctly, the only option for upscaling from Garagecoder is smoothing?

fx_gcd_upscale_patch2x 2,1

What is the difference between “patch” and “tile”. A link to a documentation would be very helpful. F1