Watermarking techniques are used as a solution to copyright protection of digital media files. In this work, a new and robust watermarking method that is based on spatio-frequency (SF) representations is presented. We use the discrete evolutionary transform calculated by the Gabor expansion to represent an image in the SF domain. A watermark is embedded onto selected cells in the joint SF domain. Hence by combining the advantages of spatial and spectral domain watermarking methods, a robust and perceptual method is presented.