HACHADI et HADIBI, Youness et Nisrin2020-11-182020-11-182020http://dspace.univ-msila.dz:8080//xmlui/handle/123456789/20696With the rapid advancement in the use of digital images in many applications, it is important to protect confidential photo data from unauthorized access. In this work devoted to the graduation thesis, we have presented an encryption algorithm that can be applied to gray images, and that depends on the combination of two algorithms, the first algorithm is based on a chaotic logistic map, the second algorithm is based on Clifford chaotic system. Analyzes of this presented image encryption algorithm show that it offers a very competitive performance.endigital images, confidential image, encryption, chaotic logistics map, Clifford System.Thesis