Image-based form document retrieval

We address the problem of image-based form document retrieval. The essential element of this problem is the definition of a similarity measure that is applicable in real situations, where query images are allowed to differ from 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°) and variations in the geometrical proportions of the form layout. This similarity measure also has a good tolerance to line detection errors. We have developed a prototype form retrieval system which has been tested on a database containing 100 different kinds of forms