This paper presents an algorithm aimed at the integrity protection of 3D models represented as a set of vertices and polygons. The proposed method defines a procedure to perform a fragile watermarking of the vertices’ data, namely 3D coordinates and polygons, introducing a very small error in the vertices’ coordinates. The watermark bit string is embedded into a secret vector space defined by the Karhunen–Loève transform derived from a key image. Experimental results show the good performance of the method and its security.
The historical perspective provides an overview of how to study flowcharts in a school informatics course. Computer applications and Internet services are considered that automate the development of flowcharts. It is shown how 3D technologies can help an informatics teacher in preparing 3D models for the study of flowcharts.
Fragile Watermarking of 3D Models in a Transformed Domain