Use of colour in form layout analysis

Colour has long been viewed as one of the unnecessary features in any form processing system, due not only to the large storage requirement and computational cost its inclusion imposes but also to the complexities of hue, chroma and brightness variation. However, as technology has advanced and computing costs have reduced, the processing of documents in colour has now become practical. This paper describes a prototype form extraction system that utilises colour information to help facilitate data extraction from a form. Blank forms are first automatically analysed to obtain their layout, colour and statistical information. The filled data is then extracted from the filled forms using techniques based upon the colour characteristic changes that have occurred with respect to the blank form. The improved performance of the proposed method has been verified by comparing the processing time, data extraction precision and recall rate of the proposed system to that of an archetypal black and white form extraction system.