DCT Image Compression and Secure Deduplication with Efficient Convergent Key Management

As our use and reliance of computer grows day by day we need an efficient way to manage our large amount of data. Sometimes a person has to use large amount of images like webpages or catalogs need to use some techniques for image compression. This is because the amount of space required to hold large amount of image can be prohibitively large in terms of cost. Fortunately we have several method of image compression available today. Discrete Cosine Transform separates images into parts of different frequencies. In a step called quantization in DCT the less important frequencies are discarded. Then for decompression process only most important frequencies are considered to recover the image. Management of large amount of data has become one of the greatest problem in todays cloud storage services. For data management a technique called Deduplication is introduced. Deduplication avoids duplicate copies being stored in the cloud. Convergent encryption is an efficient way to enforce deduplication. But the problem in making convergent encryption possible is the management of large number of keys. To this end for the management of keys we propose a new technique called Dekey. We implement Dekey using visual cryptography. This paper proposes Dekey for convergent key management, DCT image compression for minimizing storage space and for improving security and deduplication for avoiding redundant copies.