| 摘要: |
| 兼顾加密JPEG图像的隐藏容量和安全性，提出一种JPEG比特流加密域可逆数据隐藏新方法。该算法设计了一种块间置乱与块内加密相结合的JPEG比特流加密方法，不仅实现对图像块的伪随机置乱，还实现了熵编码块的霍夫曼编码和扩展位的全加密，降低信息泄露可能性的同时，提高了算法抵抗唯密文攻击的能力。同时，该算法生成的加密JPEG比特流与JPEG解码标准兼容，解码得到的加密图像类似随机噪声且与原始图像大小相同，所有图像块熵编码都可以用来隐藏附加信息，有效解决了隐藏容量与安全性之间的矛盾。对比分析了算法的安全性、文件大小和隐藏容量等性能。实验仿真结果表明本文算法能有效抵抗唯密文攻击，隐藏容量是现有最新同类算法的4倍以上。 |
| 关键词: 可逆数据隐藏 图像加密 JPEG比特流 隐藏容量 唯密文攻击 |
| DOI：10.19363/J.cnki.cn10-1380/tn.2018.11.05 |
| 投稿时间：2018-08-15修订日期：2018-10-03 |
| 基金项目:本课题得到国家自然科学基金（No.61872303，No.61461047）和四川省科技厅科技创新人才计划（No.2018RZ0143）的资助。 |
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| Larger-Capacity Reversible Data Hiding in Encrypted JPEG Bitstream |
| ZHENG Mengyang,LI Zenghui,CHEN Tansheng,DONG Mengyao,HE Hongjie,CHEN Fan |
| School of Information Science and Technology, Southwest Jiaotong University, Chengdu 611756, China;School of Mao Yi Sheng Honors, Southwest Jiaotong University, Chengdu 611756, China;School of Mathematics, Southwest Jiaotong University, Chengdu 611756, China |
| Abstract: |
| Considering the embedding capacity and security of encrypted JPEG images, a new method of reversible data hiding in encrypted JPEG bitstream is proposed. The proposed method designs a JPEG bitstream encryption method which combines inter-block scrambling and intra-block encryption. It not only realizes pseudo-random scrambling of entropy coding blocks, but also implements full encryption of entropy coding blocks including Huffman coding and extension bits. This reduces the possibility of information leakage and improves the ability of the algorithm to resist the only-cipher attack. Moreover, the encrypted JPEG bitstream generated by the proposed algorithm is compatible with the JPEG decoding standard, and the decoded encrypted image is similar to random noise and has the same size as the original image. This allows all entropy coding blocks in JPEG image to be used to hide additional information, effectively solving the contradiction between embedding capacity and security. Performances of the algorithm, including security, file-size of marked-encrypted JPEG image and embedding capacity are compared and analyzed. Experimental results demonstrate that the proposed algorithm is not vulnerable to the only-cipher attack and the embedding capacity is more than 4 times that of the latest similar algorithm. |
| Key words: reversible data hiding image encryption JPEG bitstream embedding capacity only-cipher attack |
