A new selective image encryption approach using hybrid chaos and block cipher

Transmitted images may nave different applications, inch ai commercial, military and medical applications. So It Is necessary to encrypt Image data before transmission over the network to preserve its security and prevent unauthorized access. Applying the international data encryption algorithm (IDEA) over the whole image is time consuming and provides low correlation between the original image and the decrypted image especially at low signal-to-noise ratio (SNR) values. In this paper, a new selective encryption technique based on a combination between Arnold´s cat map, image hiding, and modified IDEA techniques is presented. The proposed technique results in highly correlated original and decrypted images at low SNR values. Furthermore, it saves about 90% of the total process run time compared to the original IDEA technique. The results show that the proposed cipher has satisfactory security and is more efficient than IDEA which nukes it a potential candidate for encryption of multimedia data.