1. A method of generating a computer executable chart visualization from a static image of said chart visualization, the method comprising the steps of: identifying said static image of said chart visualization; identifying a set of pre-defined chart elements; identifying one or more portions of said static image as corresponding to one or more respective pre-defined chart elements; determining a mapping between said one or more portions of the static image and said one or more respective pre-defined chart elements; determining visual properties of each of said one or more portions of said static image; and generating a declarative description of the chart visualization by setting the visual properties for each of said one or more respective pre-defined chart elements.