jerryxie96 / imagesecuredemo

Demo of Image Searching System by SecureKnn and PCA

ImageSecureDemo

Abstract: As the development of cloud service, many people are going to upload their data (chat log, photos, etc.) to cloud server. But cloud service provider will maybe steal user’s data because of various kinds of reasons. In this report, we use secure kNN and PCA to protect user’s photos when user wants cloud server to search some photos. We divide the whole searching process into four parts. Client generates the feature vectors, encrypts the photos and decrypts the key set. Search server stores the feature vectors, searches and returns the results. Photo storage server stores the encrypted photos and relationship between ID and photo. Key storage server stores the encrypted key set. These three servers can’t collude because they are from three different cloud servers. In secure kNN, we use the work from University of Hong Kong, this equation: 0.5r(d(p2,q)-d(p1,q))>0 to ensure the result is correct and the search server only know the encrypted vectors. We implemented secure kNN by Java and use linked list to organize similar photo’s nodes in the same list to improve the efficiency. We also extend the vector dimensions so that we improved the security. We also use keyword-based semantic extension search to search photo by keywords.