Abstract
Recently, several image encryption schemes based on chaotic maps have been proposed. Nevertheless, most of them hinder the system performance, security, and suffer from the small key space problem. This paper presents an efficient hybrid image encryption scheme based on a cyclic elliptic curve and chaotic system that overcomes these disadvantages. The new scheme generates an initial keystream based on chaotic system and an external secret key of 256-bit in a feedback manner. Then, the generated keystream are mixed with key sequences derived from the cyclic elliptic curve points. Thorough encryption performance and security analysis ascertains efficacy of the proposed encryption scheme. (C) 2012 Elsevier GmbH. All rights reserved.