Chaos and DNA coding technique for image cryptography

In today's cybersphere, cryptography plays a vital role in various fields. Image encryption is an integral part for securing information because of its vast application areas such as military (defense), multimedia, healthcare and so forth. In this article, an image encryption algorithm for both grayscale and color image is proposed based on Tangential Delay‐Ellipse Reflecting Curve System (TD‐ERCS) chaotic map system and deoxyribonucleic acid (DNA) coding. Chaotic map is used to scramble the pixel positions; to achieve confusion and for creation of mask image, and DNA coding is used for changing the pixel values; to achieve diffusion. Upon experimental analysis, proposed work achieved significantly high mean square error and low peak signal to noise ratio, almost zero correlation, high number of pixel change rate and unified averaged changed intensity values, and resistance to noise and data loss attacks. In addition, the decryption is possible without loss in quality of image.