Pixel Pal is a project I have started whose purpose is to bring new life to old icon themes. Many old icon themes are in raster format and are not available for HiDPI screens (their resolution are too small). Currently the only way to handle old icon themes is to resample them by the desired factor, but the icons look pixelated.
Here is a link to a PDF showing progress in the project. The PDF showcases various models performing data augmentation. The results are still blurry
|32 x 32 pixel version of the icon||32x32 augmented with one of the models||64x64 pixels version of the icon|