An Approach to Image Compression with Partial Encryption without sharing the Secret Key

Existing methods when employ compression there is no consideration of security, similarly when it describe encryption there is no consideration of size i.e. compression. In this paper a simultaneous image compression and encryption scheme is discussed. The order of the two processes viz. compression and encryption is EC i.e. image encryption is performed first then the image compression is applied. For image encryption a symmetric key cryptography multiplicative cipher is used. Similarly for compression Discrete Cosine Transform is used. In the proposed approach a private key cryptography is used for encryption without sharing the secret key. But image transmission is required two times. Therefore to save the bandwidth partial encryption is carried out. Image compression is concerned with minimizing the number of bit required to represent an image. Image Encryption is hiding image from unauthorized access with the help of secret key that key can be private or public. Key word