Reference line extraction from form documents with complicated backgrounds

Form document analysis is one of the most essential tasksin document analysis and recognition. One of the most fundamentaland crucial tasks is the extraction of the referencelines which are contained in almost all form documents.This paper presents an efficient methodology for the complicatedgrey-level form image processing. We construct anon-orthogonal wavelet with adjustable rectangle supportsand offer algorithms for the extraction of the reference linesbased on the strip growth method using the multiresolutionwavelet sub images. We have compared this system with thepopular Hough transform (HT) based and the novel orthogonalwavelet based methods. As shown in the experiments,the proposed algorithmdemonstrates high performance andfast speed for the complicated form images. This system isalso effective for the form images with slight skew.