简介: |
Digital watermarking is the science of imperceptibly and robustly embedding additional information into host signals such as image, video, audio, software, etc. The applications of digital watermarking can be copyright protection, content authentication, data hiding, quality evaluation, etc. Among other requirements, a watermarking algorithm should meet the requirements of imperceptibility, robustness, security, and data capacity. In this presentation, the digital watermarking’s principle, applications, requirements, the start of arts, and challenges will be introduced.
Then two of the major achievements in this research area: rotation, scaling, and translation (RST) invariant image watermarking, and image and speech quality evaluation based on watermarking will be reported. RST attacks are the most challenging attacks to image watermarking and one of the most challenging attacks to video watermarking, since even a slight rotation or scaling can defeat a normal watermarking algorithm. Prof. Zhao have proposed several novel and practical watermarking algorithms that are invariant to RST. For quality evaluation, the algorithms for evaluating the quality of image and speech will be introduced. Based on discrete wavelet transform and quantization, these quality evaluation algorithms do not need original signal or a complex model, and they are very accurate and promising. And the watermarking based quality evaluation algorithms are also extended to audio and video signals. |
