رمزگذاری تصویر رنگی با استفاده از رمزنگاری مبتنی بر DNA Color image encryption using DNA based cryptography

1 Introduction Data are vulnerable and need utmost security when they are getting transferred from source to destination. Encryption is one of the most formidable ways to keep our data and information safe between two endpoints. It makes data impenetrable and unread-able, so even it ends up getting in wrong hands it is mostly useless [1]. DNA (deoxyribonucleic acid) is a genetic information carrier from parent organisms to the newly forming organism. The methodologies of encryption in which compo-nents of DNA are used to hide plain text from eavesdropper or unauthorized users in the network come under the study of DNA cryptography [2]. In DNA cryptography, the four chemical bases of DNA namely adenine (A), guanine (G), cytosine (C) and thymine (T) has so far majorly been used in addition to cryptographic algorithms but with advancement in the study of other components like Amino acids are also brought into the play [3]. Considering ‘ATGC’ to be a code we can have 24 combinations of it like ‘CTAG’, ‘TAGC’ etc. (4! = 24). Although among the 24 combinations only 8 are possible in a real life occasion as ‘A’ can combine only with ‘T’ and ‘C’ combines only with ‘G’ following the properties of DNA [3]. But, here we shall use all the 24 combinations to encrypt our data. This will increase the complexity of detecting patterns in the encrypted text. In the study of cryptography, an image which contains information is converted to an unreadable or unrecognizable form by using algorithms. This field is gaining much popularity as image can carry vital information with them. The capacity of carrying information is also more by an image. In image encryption methodologies, the pixels of original images are either manipulated of information is laid inside the image using the image as a cover to protect the data from undesired receivers [4]. Image encryption enables passing of data over unsecured networks like the internet. Without the correct key, the correct decryption to retrieve the original is a major challenge to high-end super computers [5]. Although image encryption might require more than normal text encryption but it is more formidable. Image encryption plays a vital role in securing the transmission of important government document images, images of military, healthcare and other private images [6]. Section 2 gives a background of work relating to image encryption and DNA cryptography together; Sect. 3 provides the description of proposed algorithm, utility of some of its steps and the entire algorithm; Sect. 4 documents the result analysis and Sect. 5 concludes the paper.