Partial image encryption using block wise shuffling and chaotic map

Multimedia security has become extremely important with the extensive use of multimedia data over the open-natured wireless channel. The total encryption performed by other techniques like SCAN based technique is very complex in nature and consumes a lot of computational time. However, certain applications like Pay-TV or Payable Internet Imaging Albums do not require total encryption, but requires a part of the multimedia data to be transparent to all users. This paper presents a partial image encryption based on block wise shuffling with the help of chaotic map. Pixel positions are permuted with in the block by using chaotic map. Partial encrypted images are obtained by selecting the different block size. The MSE and NPCR comparison of proposed technique with the existing encryption techniques shows that the proposed technique gives better security than the existing techniques. Decryption follows the reverse process of encryption. The analysis and experimental results show that the proposed scheme can achieve the concept of partial encryption.