Digital Watermarking Algorithm For Color Image Based On Quaternion Fourier Transform

This paper mainly introduces a color image digital watermarking algorithm based onquaternion Fourier transform.The advantage of processing color image with quaternion the-ory is that three color channels of the image are treated as a whole. Color host image isdescribed as a quaternion matrix.We can get its frequency domain information, using quater-nion Fourier transform.The watermarking information is embedded into the frequency do-main information of the host,using Arnold transform.Thus,we can get a color image con-taining watermarking information, using inverse quaternion Fourier transform of the hostfrequency domain information we get before.Information hiding is enabled.Each steps arereversible here,so the watermarking extraction process is opposite to the above process. Inthis paper,we discuss in detail the question that the real part of inverse quaternion Fouriertransform is zero or not, ensuring the feasibility of the algorithm theoretically. The experi-ment demonstrates the efectiveness of the algorithm.