DOI: 10.36347/sjet

Pages: 1-5

The security becomes an important issue of communication and storage of image due to the growth of multimedia application. Encryption is one of the ways to ensure high security. Images are used in many fields such as military and medical science. They are stored or transferred through network, security of such image data is important. Encryption involves applying special mathematical algorithms and keys to transform digital data into cipher code before they are transmitted and decryption involves the application of mathematical algorithms and keys to get back the original data from cipher code. Information privacy becomes a challenging issue. In order to protect valuable data or image from undesirable readers, image encryption and decryption is essential. In this approach, encryption phase by using selective encryption technique original image pixel values are completely concealed so that an attacker cannot obtain any statistical information from an original image. An encoder quantizes the sub images and Hadamard transform is applied to reduce the data amount. At the receiver side with the cryptographic key, the principal content with higher resolution can be reconstructed when more bit streams are received. The quality of the reconstructed image is measured by calculating peak signal to noise ratio (PSNR).