Use RealName string as contextual filter

What i have set up in views is:
aaa/%/images
aaa/%/videos

User nb.3 has "TomJ" as username, and "Tom Jones" as RealName.
What is by default is:
aaa/3/images
aaa/3/videos

and this also:
aaa/tomj/images
aaa/tomj/videos

What i would like to get is:
aaa/tomjones/images
aaa/tomjones/videos

I have spent many hours to figure this one but no results yet.