I quickly drew up a Bump map for demonstration purpose so don't expect much and using this plug-in, made a normal.
You can find this plug-in hereFor those of you not familiar with normals, look here
You can find this plug-in here


So I used the program you showed me to attempt to smooth it out. This was my first time using it so keep that in mind. I used the magic wand to select groups of pixels and used the average to make them alike and it gave the appearance of smoothing.
I like how you can zoom in and change individual pixels, very nice.