Compressible Percheptual Image Encryption for Privacy-Preseving and Its Robusness against Attacks

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H03267
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Communication/Network engineering
• Research Institution: Tokyo Metropolitan University
• Principal Investigator: KIYA HITOSHI 首都大学東京, システムデザイン研究科, 教授 (40157110)
• Co-Investigator(Kenkyū-buntansha): 渡邊 修 拓殖大学, 工学部, 准教授 (30384697)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 画像暗号化 / 圧縮可能暗号化 / JPEG / 情報セキュリティ / SNS / クラウド

Outline of Final Research Achievements

With the wide/rapid spread of distributed systems for information processing, such as cloud computing and social networking, not only transmission but also processing is done on the internet. However, cloud environments have some serious issues for end users, such as unauthorized access, data leaks, and privacy compromise, due to unreliability of providers and some accidents. Accordingly, we studied compressible image encryption schemes, referred to as encryption-then-compression (EtC), although the traditional way for secure image transmission is to use a compression-then encryption (CtE) system. EtC systems allow us to close unencrypted images to network providers, because encrypted images can be directly compressed even when the images are multiply recompressed by providers. In addition, Images encrypted by using the proposed scheme were shown to have strong robustness against various attacks including jigsaw puzzles solvers.

Free Research Field

信号処理

Academic Significance and Societal Importance of the Research Achievements

本研究により得られた結果及びその独創性は次の通りである． (a)国際標準の画像圧縮方式に適用可能な暗号化法を世界で初めて提案した． (b)ジグソーパズル解法を世界で初めて攻撃として捉え，暗号化の安全性を評価した．
また本研究の意義は次の通りである．(a)圧縮の前に暗号化処理が実行でき，プロバイダーの信頼性が低い場合にも，画像の持つプライバシーの保護や不正利用の防止が可能となる．(b)国際標準の圧縮方式が適用可能であり，広く技術が社会に普及することを期待できる． (c)暗号化処理，情報圧縮分野の融合に相当し，これらの分野の研究に新しい視点を与え，さらに学術的に新しい分野を拓くことが期待できる