QDCT Encoding-Based Retrieval for Encrypted JPEG Images  

作　　者：Qiuju Ji Peipeng Yu Zhihua Xia 

机构地区：[1]School of Computer and Software,Nanjing University of Information Science and Technology,Nanjing,210044,China

出　　处：《Journal on Big Data》2020年第1期33-51,共19页大数据杂志（英文）

基　　金：This work is supported in part by the Jiangsu Basic Research Programs-Natural Science Foundation under grant numbers BK20181407;in part by the National Natural Science Foundation of China under grant numbers U1936118,61672294;in part by Six peak talent project of Jiangsu Province(R2016L13);Qinglan Project of Jiangsu Province,and“333”project of Jiangsu Province,in part by the National Natural Science Foundation of China under grant numbers U1836208,61702276,61772283,61602253,and 61601236;in part by National Key R\&D Program of China under grant 2018YFB1003205;in part by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)fund,in part by the Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET)fund,China.Zhihua Xia is supported by BK21+program from the Ministry of Education of Korea.

摘　　要：A privacy-preserving search model for JPEG images is proposed in paper,which uses the bag-of-encrypted-words based on QDCT(Quaternion Discrete Cosine Transform)encoding.The JPEG image is obtained by a series of steps such as DCT(Discrete Cosine Transform)transformation,quantization,entropy coding,etc.In this paper,we firstly transform the images from spatial domain into quaternion domain.By analyzing the algebraic relationship between QDCT and DCT,a QDCT quantization table and QDTC coding for color images are proposed.Then the compressed image data is encrypted after the steps of block permutation,intra-block permutation,single table substitution and stream cipher.At last,the similarity between original image and query image can be measured by the Manhattan distance,which is calculated by two feature vectors with the model of bag-of-words on the cloud server side.The outcome shows good performance in security attack and retrieval accuracy.

关 键 词：Image encryption image retrieval JPEG image QDCT BAG-OF-WORDS 

分 类 号：TP3[自动化与计算机技术—计算机科学与技术]