Image-based form document retrieval

We address the problem of image-based form document retrieval. The essentia l element of this problem is the definition of a similarity measure that is applicable in real situations. where query images are allowed to differ fr om the database images. Based on the definition of form signature, we have proposed a similarity measure that is insensitive to translation, scaling, moderate skew (<5 degrees) and variations in the geometrical proportion of the form layout. This similarity measure also has a good tolerance to line detection errors. We have developed a prototype form retrieval system based on the proposed similarity measure. Preliminary experimental results on a database containing 100 different kinds of forms are encouraging. (C) 2000 Pattern Recognition Society. Published by Elsevier Science Ltd. All rights reserved.