Self-Similarity Descriptor (Octave mex)

I want to use "Self-Similarity Descriptor" for
Image classification. So I tried to use a code
from this URL (by Visual Geometry Group).

I haven't have Matlab but Octave.
My machine condition is Ubuntu Linux.

I download the code and start Octave and
type "example", but failed.

This code includes .cpp file, so mex compile is
needed. I download "Octave3.0-headers" by

I checked "mex compile" is usable
by typing "mex" (in Octave).

I type "mex mexFindSimMaps.cpp", and
as a result, "mexFindSimMap.mex",
"mexFindSimMap.o" is generated.

Again, I typed "example",
I got 8*9976 self similarity vector!