Hello.
As I understand, you have images, and you want digitize the roads on them.
I know how to do this in other tools (not arcGIS). I can describes you the step by step what these tools do, may be arcGIS can do same too. I'm novice in arcGIS but I sure that you can digitize roads in arcGIS after I'll present the algorithm, but first step of digitizing must be performed in other program, because I'm not sure that arcGIS can do same thing.