A framework for automatic image colorization, the art of adding color to a monochrome image or movie, is presented in this paper. The approach is based on considering the geometry and structure of the monochrome luminance input, given by its gradient information, as representing the geometry and structure of the whole colored version. The color is then obtained by solving a partial differential equation that propagates a few color scribbles provided by the user or by side information, while considering the gradient information brought in by the monochrome data. This way, the color is inpainted, constrained both by the monochrome image geometry and the provided color samples. We present the underlying framework and examples for still images and movies. © 2005 IEEE.