Design of information hiding in image

• Main Author: Cao, Yun
• Other Authors: Ma Maode
• Format: Thesis-Master by Coursework
• Language: English
• Published: Nanyang Technological University 2019
• Subjects: Engineering::Electrical and electronic engineering::Electronic systems::Signal processing
• Online Access: https://hdl.handle.net/10356/136505
• Institution: Nanyang Technological University

With the development of the Internet, storage and transmission technologies such as printers and scanners, digital multimedia products are rapidly transmitted through the Internet broadcasting, multimedia works becoming easy to obtain and illegally tampering and copying. The copyright of media works urgently needs to be protected. The development of cryptography and information security technologies has provided support for content security and copyright protection for multimedia works. As an important information security scheme, digital watermarking technology provides a powerful solution to the protection of multimedia works. Based on the previous work, this paper completed the following work in response to the current development of digital watermarking. 1) Understand the characteristics, classification and application of digital watermarking technology, review the research background of digital watermarking technology, study several common transformations of image domain watermarking in transform domain and image scrambling technology, based on existing algorithms. An image digital watermarking algorithm combining discrete wavelet transform, discrete cosine transform and matrix singular value decomposition and new scrambling technique is proposed. According to the shortcomings of related algorithms, grayscale scrambling and pseudo magic square transform is used to improve the robustness of the algorithm. 2) Experiments based on Python 3.7 are made to test the proposed watermarking algorithm. All the experimental results show that the image watermarking algorithm based on DCT-DWT-SVD and scrambling proposed in this paper has strong imperceptibility and robustness. When the watermark is added, the image undergoes common signal processing such as chopping, rotation, filtering, etc. After that, the presence of the watermark can still be detected and the calculation speed is faster.