Image encryption with chaotic system-strengthened hybrid RC4 and RSA algorithms: security and performance analysis

This thesis investigates the role of encryption algorithms in ensuring the security of digital images, with a particular focus on the effects of hybrid approaches strengthened by chaotic systems on both security and performance. The increasing demand for data protection at both individual and organizational levels makes it essential to safeguard images not only rapidly but also securely, thereby emphasizing the need for advanced encryption techniques. Within this scope, a hybrid method is proposed by combining the RC4 algorithm with a Logistic Map-based chaotic system. In addition, the proposed approach is comparatively evaluated against classical RC4, AES, and chaotic AES algorithms. Experimental studies are conducted on both color and grayscale images, and the obtained results are analyzed in terms of encryption and decryption times to evaluate performance. Furthermore, security robustness is assessed using histogram analysis, pixel correlation, and entropy measurements. The findings indicate that although RC4 demonstrates superior performance in terms of computational speed, chaotic-based hybrid approaches achieve more effective results with respect to security metrics. This study demonstrates that chaotic hybrid encryption methods provide a more resilient and reliable alternative for image security, contributing to both academic research and practical applications.