image processing
Seeing Your Image under a Signal Theory point of view, You can simply use methods like Fourier Descriptors. If You consider the Image how a stocasthic Process, You can apply methods like Supervisioned Classification, but it's a bit difficult if You aren't expert on Matlab programming and Remote Sensing & Digital Image Processing.
An other approach is to use the Fuzzy Logic, but I'm not expert in this Discipline, so I can't tell You about this!