Color seal extraction from documents: Robustness through soft data fusion

This paper presents a framework for the extraction of elements characterized by a particular color hue from color document images. The presented approach attains the detection of official seals, which will be thence analyzed by an embedding system in order to detect possible falsifications. The framework is based on the fusion operator denoted as fuzzy integral, whose robustness with respect to changes in the luminance and the saturation of particular hues is due to the use of the ranking among the input data as an influencing factor in the fusion result. The approach is evaluated on a real data set of tax forms delivered by custom houses, showing its successful performance.