A practical multipurpose watermarking scheme is proposed for color image and video?s copyright protection and authentication, which embeds a robust watermark and a reversible fragile watermark into different color components of a color image or video original frame. The robust watermark is constructed utilizing the method of square deviation modulation on image block coefficient distribution; and the reversible fragile watermark is employed utilizing a scrambled LSB embedding scheme for lossless authentication of copy-watermarked image. Simulation results show that the reversible fragile watermark has a bit-exact tampering detection ability while the robust watermark has a strong robustness to common distortions in practical applications such as small rotation, JPEG, filtering, brightness and contrast enhancement and additive Gaussian noise, etc.