Discrete-quaternion-Fourier-transform-based registration method for color images

The descriptive capability of color images for a scene is better than that of grayscale images. Traditional registration methods to register color images convert them to grayscale ones, in which the registration precision is decreased due to the loss of color information. By extending some properties of the discrete Fourier transform to the quaternion domain, a discrete-quaternion-Fourier-transform-based registration method for color images is proposed in this paper. Color images are represented in quaternion form, and the parameters in the rotation-scale-translation model are recovered using the rotation and the scale properties of DQFT and the quaternion phase correlation. Finally the color images are registered through image translation using the recovered parameters. The method proposed in this paper, in which color images are processed holistically, achieved high registration precision.