HYBRID METHODS OF PICTURE ENCRYPTION AND DECRYPTION: AN ANALYTICAL STUDY

Abstract

To encrypt digital media, the majority of imaging techniques use symmetrical and asymmetric cryptography algorithms. In the literature, most of the academic papers concentrate mainly on the Advanced Encryption Standard (AES) encryption and decryption algorithm. This paper proposes an analysis of Elliptic Curve Cryptography (ECC) with Hill Cipher (HC), ECC with Advanced Encryption Standard (AES) and ElGamal with Double Playfair Cipher hybridization for image encryption and decryption by hybridization (DPC). This study is based on the following parameters: I time of encryption and decryption, (ii) encrypted image entropy, (iii) decrypted image intensity loss, (iv) PSNR (Peak Signal to Noise Ratio), (v) Number of Pixels Changing Rate (NPCR), and (vi) Unified Average Changing Intensity (UACI). The hybrid method involves the speed and ease of symmetric algorithm implementation, as well as enhanced asymmetric algorithm security. Asymmetric key cryptography is supported by ECC and ElGamal cryptosystems, while symmetric key algorithms include HC, AES, and DPC.