DC: Signal ⊑ ����: ������������ ���������� �� � }�� ���������������� ��: ������ ��}

The above cited concepts are extended by relations to other classes or data. As an example, the data property Geom:has\_Bounding\_Box aims to store the placement of the detected object in a bounding box defined by its eight 3D points characterized by x, y and z values each one.

To specify its semantic characteristics, new classes are created, aiming to characterize a semantic object by a set of features like colour, size, visibility, texture, orientation and its position in the point cloud. To do so, new object properties axioms like Geom:has\_Color, Geom:has\_Size, Geom:has\_Orientation, Geom:has\_Visibility and Geom:has\_Texture are created linking the DC:DomainConcept class to the Charac:color", Charac:size, Charac:Orientation, Charac:Visibility and Charac:Textureclasses axioms respectively.

Fig. 8. Example of the DB scene objects modelling.

#### **Layer of the geometric knowledge**

Geometrical knowledge formulates geometrical characteristics to the physical properties of scene elements. In the simplest case, this information might be limited to few coordinates expressing a bounding box containing the object. However, for elements being accessible to functional descriptions, additional knowledge will be mentioned. A signal, for example, has vertical lines, which needs to be described by a line equation, its values and completed by width and height. In fact, we think that such knowledge can present a discriminant feature able to improve the automatic annotation process. For this reason, we opt to study the different geometric features related to the cited semantic elements, then, use only the discriminant one as basic features for a given object. The following table gathers the object characteristics together regarding the properties of a bounding box, Table 2, Fig 9.

Fig. 9. The geometry class hierarchy.

232 Semantics – Advances in Theories and Mathematical Models

DC: Signal ⊑ ����: ������������ ���������� �� � }�� ���������������� ��: ������ ��} The above cited concepts are extended by relations to other classes or data. As an example, the data property Geom:has\_Bounding\_Box aims to store the placement of the detected object in a bounding box defined by its eight 3D points characterized by x, y and z values

To specify its semantic characteristics, new classes are created, aiming to characterize a semantic object by a set of features like colour, size, visibility, texture, orientation and its position in the point cloud. To do so, new object properties axioms like Geom:has\_Color, Geom:has\_Size, Geom:has\_Orientation, Geom:has\_Visibility and Geom:has\_Texture are created linking the DC:DomainConcept class to the Charac:color", Charac:size, Charac:Orientation, Charac:Visibility

Geometrical knowledge formulates geometrical characteristics to the physical properties of scene elements. In the simplest case, this information might be limited to few coordinates expressing a bounding box containing the object. However, for elements being accessible to functional descriptions, additional knowledge will be mentioned. A signal, for example, has vertical lines, which needs to be described by a line equation, its values and completed by width and height. In fact, we think that such knowledge can present a discriminant feature able to improve the automatic annotation process. For this reason, we opt to study the different geometric features related to the cited semantic elements, then, use only the discriminant one as basic features for a given object. The following table gathers the object

characteristics together regarding the properties of a bounding box, Table 2, Fig 9.

and Charac:Textureclasses axioms respectively.

Fig. 8. Example of the DB scene objects modelling.

**Layer of the geometric knowledge** 

each one.


Table 2. Geometric characteristics overview.
