I have seperated the icons of my Android Application into two types, the small ones that include icons approximatelly from 28 x 28 dp until 32 x 32 dp, and the large ones, that are icons 60 dp x 60 dp. I have to tell to my designer the number of pixels, the icons need to be done. So for the small icons I keep the standard guidelines for the different densities:
xxhdpi: 144px xhdpi: 96px hdpi: 72px mdpi: 48px
For the bigger ones my basic thought is, that they cover 4 times bigger surface, so the pixels must be 4 times larger to keep the same quality:
xxhdpi: 576px xhdpi: 384px hdpi: 288px mdpi: 192px
Should I keep those ones or should I go back to the standard guidelines conserning the bigger icons?
the icon set for an android application just needs the following resolutions: xxhdpi: 144px xhdpi: 96px hdpi: 72px mdpi: 48px There's no need to use big or small icons, since you can just define one set in the manifest.
if you want to adapt other images to different densities, just follow the above relationship: 4:2:1.5:1