The Color Image Digital Watermarking Algorithm Based on Coordinate Transformation and Quaternion Fourier Transform

With the rapid development of information technology and Internet technology, people can easily exchange and transmit digital information, which not only brings convenience to people's work and life, but also brings rampant piracy of digital media. In the face of the temptation that pirated digital media can obtain huge benefits, some people are desperate to steal digital media works without copyright and sell and spread them at will. In this case, digital media copyright protection and anti-theft version authentication are very important measures to solve the current problems, and digital watermarking(DW) technology is an important method of digital media copyright protection and authentication, so it is more and more concerned and studied by researchers. This paper mainly studies the color image DW algorithm based on coordinate transformation and quaternion Fourier transform, including quaternion representation of color image, Fourier transform analysis, log polar transformation, watermark embedding and watermark extraction. Experimental results show that in the noise range, the smaller the compression ratio is, the more complete the watermark information can be extracted. When the image compression ratio reaches 80%, the watermark information can be completely extracted.