Watermarking of Digital Images in Frequency Domain

• Published in: International journal of automation and computing Vol. 7; no. 1; pp. 17 - 22
• Main Authors: Baba, Sami E. I., Krikor, Lala Z., Arif, Thawar, Shaaban, Zyad
• Format: Journal Article
• Language: English
• Published: Heidelberg Institute of Automation, Chinese Academy of Sciences 01.02.2010; Springer Nature B.V; Faculty of Information Technology, Applied Science University, Amman 11931, Jordan
• Subjects: Alternating current; CAE) and Design; Color; Computer Applications; Computer-Aided Engineering (CAD; Control; Digital imaging; Discrete cosine transform; Engineering; Frequency domain analysis; Frequency domains; Logos; Mathematical analysis; Mechatronics; Pseudorandom; Robotics; Watermarking; 位图图像; 原始图像; 图嵌入; 水印图像; 离散余弦变换; 随机性; 频域; 颜色分量; RC4; JPEG; discrete cosine transform (DCT); pseudorandom bit generator; Watermarking
• ISSN: 1476-8186; 2153-182X; 1751-8520; 2153-1838
• DOI: 10.1007/s11633-010-0017-7

Invisible watermarking methods have been applied in frequency domains, trying to embed a small image inside a large original image. The original bitmap image will be converted into frequency domain to obtain the discrete cosine transform （DCT） matrices from its blocks. The bits of the logo image are embedded in random color components of the original image, as well as in random positions in each selected block. These positions are alternating current （AC） coefficients of the DCT matrix. The randomness is obtained from RC4 pseudorandom bit generator that determines in which color component this logo image bits will be embedded. The embedded bits have been hidden in random blocks in the image, which are chosen according to a （semi-random） function proposed in this work.