中文摘要：

利用图像测试，提出了一种可分离加密域可逆数据隐藏算法，能获得质量较高的直接解密图像．加密方在图像流加密之前进行图像测试并生成位置图，嵌入方根据位置图将秘密信息嵌在选中像素的高位，接收方在相邻像素相关性基础上通过一种自适应差值算法实现可逆性．若全部嵌在选中像素的第8位，得到的直接解密图像质量较差；若全部嵌在选中像素的第7位，则无法实现无失真恢复．针对这两个缺点，该文在保证无失真恢复同时获得了质量较高的直接解密图像．实验表明所提出的算法有效，且性能优良．

英文摘要：

In this paper, a separable reversible data hiding method in encrypted images is proposed. The content owner tests an original uncompressed image and generates a location map before embedding. The data-hider embeds additional data into significant bits of the selected pixels according to the location map with an embedding key. At the receiver side, the original image can be perfectly recovered by a context adaptive interpolation algorithm based on spatial correlation of adjacent pixels. If all additional data are embedded into the most significant bits of the selected pixels, quality of the directly decrypted images are poor, and if all data are embedded into the second most significant bits, perfect restoration of the original image cannot be achieved. To resolve these problems, the proposed method can ensure both good quality of the directly decrypted images and error-less restoration. Experimental results show validity and good performance of the method.