[Studies in Computational Intelligence 481] Artur Babiarz, Robert Bieda, Karol Jędrasiak, Aleksander Nawrat (auth.), Aleksander Nawrat, Zygmunt Kuś (eds.) - Vision Based Systemsfor UAV Applications (2013, Sprin

32 R. Bieda et al.
- elongation „surface-moment” factor:
4
(15)
Vector design features describing the objects is shown in the table 1.
Table 1. The vector design features
L.P. The name of the feature No.
1 The X coordinate of the geometric center of the area - -
2 The Y coordinate of the geometric center of the area -
-
3 Hydraulic radius (ratio of surface area to the circuit area) (8)
4 The diameter of the circle with an surface equivalent to the area (9)
5 Axis of the ellipse corresponding to the ratio of the area (14)
6 The ratio of the dimensions of the rectangle corresponding to the area (11)
7 Elongation factor (13)
8 The compactness factor (10)
9 Roundness factor (12)
10 „Surface-moment” factor (15)
11 Normalized moment of geometric order 2 ··η (6)
12 Normalized moment of geometric order 2 ··η (6)
13 Normalized moment of geometric order 2 ··η (6)
14 Normalized moment of geometric order 3 · · η (6)
15 Normalized moment of geometric order 3 · · η (6)
16 Normalized moment of geometric order 3 ··η (6)
17 Normalized moment of geometric order 3 · · η (6)
18 Torque invariant Hu 1 (7.a)
19 Torque invariant Hu 2 (7.b)
20 Torque invariant Hu 3 (7.c)
21 Torque invariant Hu 4 (7.d)
22 Torque invariant Hu 5 (7.e)
23 Torque invariant Hu 6 (7.f)
24 Torque invariant Hu 7 (7.g)
The first two features of the x vector do not carry a strict information about the
properties of the object, but only information about the location of the object in
the image. These figures were, however, included in the feature vector due to the
overriding task that they have been confronted with the vision system, a task associated
with the detection of the object and its location in the surroundings of the
UAV unit.
In the process of describing and object recognition using feature X vector only
22 elements were actually used.