Automatic Removal of Marginal Annotations in Printed Text Document

TL;DR

This paper presents a two-stage algorithm for automatically removing handwritten marginal annotations from printed documents, effectively recovering the original text with high accuracy without requiring the original document.

Contribution

A novel two-stage method combining marginal boundary detection and connected component analysis to remove annotations and restore original printed text.

Findings

89.01% accuracy in removing marginal annotations

97.74% accuracy in retrieving original printed text

Validated on 50 complex annotated documents

Abstract

Recovering the original printed texts from a document with added handwritten annotations in the marginal area is one of the challenging problems, especially when the original document is not available. Therefore, this paper aims at salvaging automatically the original document from the annotated document by detecting and removing any handwritten annotations that appear in the marginal area of the document without any loss of information. Here a two stage algorithm is proposed, where in the first stage due to approximate marginal boundary detection with horizontal and vertical projection profiles, all of the marginal annotations along with some part of the original printed text that may appear very close to the marginal boundary are removed. Therefore as a second stage, using the connected components, a strategy is applied to bring back the printed text components cropped during the first stage. The proposed method is validated using a dataset of 50 documents having complex handwritten annotations, which gives an overall accuracy of 89.01% in removing the marginal annotations and 97.74% in case of retrieving the original printed text document.