An Efficient Adaptive of Transparent Spatial Digital Image Encryption

Digital images are important information often contain high confidential and secret data need to be protected. Due to the growth in the adoption of multimedia technologies, many digital images are being stored on the end user devices. Nevertheless, most of the researches mainly focus on protecting these digital images through transmission and protection on the spatial domain is relatively less. However the large size and complex structure of digital images make the computational overhead and processing time needed to carry out full encryption is a major bottleneck especially in real time applications. This paper firstly describes the current spatial data files protection methods based on transparent encryption technology, and then proposes an efficient model for transparent encryption and decryption on the fly for digital image files stored on hard disk. The proposed method takes advantages of partial image encryption using symmetrical ciphers. Furthermore, to reduce the perceivable information for other unencrypted parts, the transformation technique is proposed to shuffle the image blocks and to decrease the correlation among image elements. By using this proposed method, a sufficient level of security can be achieved within a reasonable computational complexity.