[Solved] How do I filter tilemaps

I'm trying to make a filter that adds corners and slopes to a generated tilemap.

Like this:

Anyone know how to do this without this?

Or this?

I'm guessing the solution is super simple, I just can't seem to figure it out.

Edit: currently looking into using a dictionary to fill out the list of rules and then apply them automatically

Solved:

http://imgur.com/a/95vej

Summary

Dictionary stores strings of four numbers, (can be more complex, but for the sake of not sitting here for 5 hours making the rules) one for each direction, up down left right. Then it checks which sides have different tiles, and loads them into a string. That string determines the tile sprite to display.

Then I have a quick mechanic for dynamically setting/erasing tiles.