Image button size for ldpi, mdpi, hdpi, xhdpi, xxhdpi, xxxhdpi

Question

I searched the Internet for a long time, but the problem is that I am not getting the original size of the image button.

I know this ratio

ldpi is 0.75x dimensions of mdpi
hdpi is 1.5x dimensions of mdpi
xhdpi is 2x dimensinons of mdpi

So, can I take any mdpi size standard or something else.