The invention relates to the encoding and decoding of texture mapping data of a textured 3D object. A 3D object is usually represented by connectivity, geometry and property data. The texture data, belonging to the property data, include a texture image; a texture coordinates table having entries, each entry defining coordinates in the texture image; and texture indexes associating each vertex of a polygon in the 3D object with an entry in the texture coordinates table. The present invention proposes to search for and delete entry duplicates from the texture coordinates table. To reduce encoding complexity, the search and deletion are based on the connectivity data. This is to exploit redundancies between the mesh connectivity for the polygons within the 3D object and the texture connectivity for the texture polygons within the texture image.