Lin Kuang Tsan
Department of Mechanical and Computer Aided Engineering, St. John's University 499, Section 4, Tam King Road, Tamsui, Taipei County 25135, Taiwan, China.
Appl Opt. 2010 Jul 1;49(19):3814-20. doi: 10.1364/AO.49.003814.
A hybrid encoding method is used to assemble the double-random phase-encoding technique and the binary encoding method. Because the double-random phase-encoding technique is robust for noises and the binary encoding method is free of using external keys, the proposed hybrid encoding method has their advantages. The hybrid encoding method first encodes a covert image to form a complex-number matrix by using the double-random phase-encoding technique, where two random real-number matrices are used to increase the security of the encoding work. Then the elements of the two random real-number matrices and the elements of the complex-number matrix are encoded to form a binary-bit string by using the binary encoding method. Finally, the binary data in the binary-bit string are encoded into a host image to form an overt image with hidden information by using a gray-value modulation method. The decoding work is easy for authorized people, but it is very difficult for unauthorized people. Therefore, the proposed hybrid encoding method is a very useful encoding method.
一种混合编码方法被用于组合双随机相位编码技术和二进制编码方法。由于双随机相位编码技术对噪声具有鲁棒性，且二进制编码方法无需使用外部密钥，所提出的混合编码方法具备它们的优点。该混合编码方法首先通过双随机相位编码技术对一幅秘密图像进行编码以形成一个复数矩阵，其中使用两个随机实数矩阵来提高编码工作的安全性。然后，利用二进制编码方法对这两个随机实数矩阵的元素以及复数矩阵的元素进行编码以形成一个二进制位串。最后，通过灰度值调制方法将二进制位串中的二进制数据编码到一幅宿主图像中，从而形成一幅带有隐藏信息的公开图像。解码工作对授权人员来说很容易，但对未授权人员来说则非常困难。因此，所提出的混合编码方法是一种非常有用的编码方法。
