I think the sizes for point pictures are stupid because no picture or picture resizer goes to 28x28, 56x56, and 112x112. I am very displeased with this because I have been trying to set a picture for my points for an hour!
What picture resizer are you using? I haven't been able to find any that would prevent you from picking any custom size.
A quick search on the internet, and the first one lets me set any width and height, and might be what you're looking for.