Simple program to put the images in POT
if you don't know what is "Power Of Two" :
https://software.intel.com/en-us/articles/opengl-performance-tips-power-of-two-textures-have-better-performance https://www.katsbits.com/tutorials/textures/make-better-textures-correct-size-and-power-of-two.php
When executing the program select all the photos that you want to transform into "POT" after that all the Images will be saved in a new folder created where the program is called "POT"
Compiled with
pyinstaller --onefile --windowed ToPOT.py
Download : ToPOT.exe
Without POT
With POT
Script to slice Images in Unity3d https://gist.github.com/shadesbelow/8a6ddc54db795241f3cff539db6ea487