Abstract: A first digital colour image with pixels having colour values is transformed to a second digital colour image with pixels having transformed colour values, the colour values being defined in a selected colour space. Pixel clusters are formed for the first digital colour image whereby pixels of a pre-defined category are grouped into a particular cluster in the selected colour space. The colour values of the pixels in a particular cluster are transformed such that transformed colour values belong to a pre-defined area associated to the particular cluster in the selected colour space, the pre-defined area consisting of memory colours of the same pre-defined category. The second digital colour image can be rendered on a display screen or on a print medium.