ortho.py:420,421 imXLine and imYline

I'm guessing this is correct, however does it always ?assumes? Y is less than X?
It appears that X (imX.shape)  is the dimension used for both lines.

```
        #Create an array with the matrix of coordinates
        imXLine = imX.reshape((1, imX.shape[0]*imX.shape[1]))
        imYLine = imY.reshape((1, imX.shape[0]*imX.shape[1]))
```