IMPACT ResearchImage Enhancement,Segmentation,Experimental OCR

Apostolos Antonacopoulos

PRImA Lab, The University of Salford, United Kingdomwww.primaresearch.org

Outline Overview: digitisation workflow Image enhancement

Border removal Page curl removal Correction of arbitrary warping

Segmentation Recognition-based Standalone

Typewritten document OCR Wordspotting

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Overview: Digitisation Workflow

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Main steps:① Scanning② Image enhancement

Page splitting Border removal Page curl removal Dewarping

③ Layout analysis Segmentation of regions, lines, words and

characters Region classification Logical layout analysis

④ OCR (incl. specialist or wordspotting)⑤ Post-processing

Correction of Arbitrary Warping Fully-automated tool for large-scale

digitisation Interface for interactive fine correction

(e.g. for boutique digitisation projects) Arbitrary geometric artefacts correction Multi-column documents Fully-parameterised process (reversible) No adverse effects on non-warped

documents22 March 2011 – EC review4

Fully-Automated Dewarping

22 March 2011 – EC review5

Global Grid Construction

22 March 2011 – EC review6

Original Image Region Segmentation Global Grid

Sub-Grid Correction

22 March 2011 – EC review7

Sub-grid text lines

Sub-grid aligned to baselines

Corrected sub-grid

Multi-Column Document Correction

Original image Baseline-aligned sub-grids Corrected image

Preliminary Results Evaluation

calculates deviation from straight lines (shaded area)

Method compared with IMPACT page-curl removal method and with original image

22 March 2011 – EC review9

Further Information10

PRImAhttp://www.primaresearch.org

IMPACThttp://www.impact-project.eu