Image Encryption Research Based On Smartphones

With the rapid development of mobile Internet, smart device has become an integral part of life electronic products, especially smartphones. Popularity of smartphones to people’s lives has brought great convenience, but also produce some worrying problems. Currently a large number of malicious programs filled with the Internet, a serious threat to the user’s information security; and because smartphones are private property, if it was lost, it’s easily peeping into the privacy of others inside the phone, such as communications records, text messages, images, and so on. Personal information in smartphone related to the vital interests of users, and image information is more prominent.In this paper, image encryption algorithm research to design for Android smartphones image encryption algorithm as the target, the image encryption algorithm designed both for Android smartphones, such as the encryption algorithm is applied to mobile phone users, can protect users image information play an important role. The main innovation of this paper is as follows:We designed a cryptographic operations performed in the airspace image encryption algorithm, using image block and chaotic sequence of repeated use to reduce the amount of calculation, to ensure encryption effect, but also shorten the time to get the encryption process. Articles from the algorithm is analyzed theoretically, also proved the safety and feasibility of the algorithm experimentally.Currently, research on Android phones used lossy JPEG compression algorithm on the most widely, based on JPEG compression step to design a new image encryption algorithm, the first in the airspace of the 8×8 block scrambling operation, and then in frequency domain of gray-scale transformation coefficients and diffusion operations. Embedded encryption schemes are analyzed, and the compression ratio and time analysis of both the impact of encryption steps for JPEG compression using experiments. Finally, from the image entropy and correlation point of view security of the algorithm is analyzed.