**Marco Botta 1,\*, Davide Cavagnino 1, Marco Gribaudo <sup>2</sup> and Pietro Piazzolla<sup>3</sup>**


Received: 7 April 2020; Accepted: 2 May 2020; Published: 7 May 2020

**Abstract:** 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.

**Keywords:** 3D model; integrity protection; fragile watermarking; data hiding; genetic algorithm; Karhunen–Loève transform
