Privacy Preserving for Faces in Images based on Chaotic Maps and Elliptic Curve Cryptography

The rapid evolution of imaging and communication technologies has transformed images into a widespread data type. Different types of data, such as medical information, official correspondence or governmental and military documents saved and transmitted in the form of images over public networks. Cryptography is a solution to protect confidential images by encrypting before transmission over unsecure channels. This paper will focus on selective image encryption algorithm to improve and enhance the security of transmission. Selective encryption is a solution to decrease the consumed time for encryption, which reduces the encrypted regions as small as possible. Hence, a hybrid cryptosystem is proposed based on the combination of ECC and chaotic maps that detects the face(s) in an image and encrypt the selected regions. This scheme will encrypt around five percent of the whole. The results of security analysis demonstrate the strength of the proposed cryptosystem against statistical, brute force and differential attacks. The evaluated running time for both encryption and decryption processes guarantee that the cryptosystem can work effectively in real-time applications.