Watermarking provides an efficient mechanism for copyright protection of digital media by embedding information in the object to identify the owner. This paper proposed a watermarking technique that can successfully embed a grey-scale image in a 3D mesh object. In our proposed technique, each three vertices of the 3D object can hide one pixel from the secret image. The experimental results showed that the proposed technique has better visual quality on both the watermarked object and the extracted secret image.

We present a new type of mappings called centrally extended α‐homoderivations of a ring ℜ (i.e., a map H from ℜ into ℜ which satisfies H(x + y) − H(x) − H(y) ∈ Z(ℜ) and H(xy) − H(x)H(y) − H(x)α(y) − α(x)H(y) ∈ Z(ℜ) for any x, y ∈ ℜ) where α is a mapping of ℜ and discuss the relationship between these mappings and other related mappings. Also, we study their effect on the center of a ring, and we give several outcomes on the commutativity of the ring.