Fix the list of box filter sizes

[kunigundeskugel]

According to the original paper of SURF, the list of box filter sizes is as follows : Octave 4 : 51, 99, 147, 195 Octave 3 : 27, 51, 75, 99 Octave 2 : 15, 27, 39, 51 Octave 1 : 9, 15, 21, 27 However, OpenCV SURF implementation has resulted in different values : Octave 4 : 72, 120, 168, 216 Octave 3 : 36, 60, 84, 108 Octave 2 : 18, 30, 42, 54 Octave 1 : 9, 15, 21, 27

This pullrequest changes

the list of filter sizes to become consistent with the SURF paper.

[catree]

Personal thought: would be interesting to see if this improves the stability of the SURF detection. And to compare this OpenCV implementations with some other implementations, see also.

[kunigundeskugel]

Before :

After :