Why not use Moi itself ?...

At the end use the Print Screen Key and past in any 2D prog for have your image to manage ! :)

In the free Fotosketcher for example! (by a talentuous French guy) ;)
https://fotosketcher.com

(you can resize your image in 64 * 64 pixels if you want...and some other cool things!
here the process (all take 10 seconds! ;)

Past your save Screen from the ClipBoard
Crop / reframe
Permute image
Apply an effect if necessary
Resize image 64*64
Save you image 64*64
et voila :)

here just for validate the process




Here the image.jpg from fotosketcher
you can now apply your Base 64 beautity...

so the icon will be maybe something like that or smaller/bigger following the Options/ UI size of Moi...