ocr challenges in historic documents and the contribution of impact
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IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
18/08/2010 - IFLA satellite meeting, Uppsala
OCR challenges in historic documents and the contribution of IMPACTClemens Neudecker, KB National Library of the Netherlands
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Background Text that is not digital is virtually invisible
OCR (optical character recognition) technology does not produce satisfactory results for historic documents
There is a lack of institutional knowledge and expertise which causes “re-inventing the wheel”
Innovate OCR software and language technology
Share best practice and build capacity across Europe (Guidelines, Training, Workshops)
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT – Improving access to text Funded by the EC as part of the 7th Framework Programme
Coordinated by KB – National Library of the Netherlands
EU funding: € 12 100 000
26 partners: Libraries, Research Institutes, Industry Partners
Start date: 1 January 2008
Duration: 48 Months 2011: Center of Competence
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Historic material: different problems
I. OCR errorsDamaged material, bad quality scans, difficult layout,
historic fonts, …
II. Historical languageSpelling variants, orthographical variants, inflected forms, …
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Bad OCR results…
la 112 B ik e my lat arrived the>Pylades,-. lliot; aod. Abe- 3ineva, CNeee 4orn Neath,' titch ,cuim; ,'t;ohn_ IoMelwl fri ytiil SUn-.die8; ,FrietndiLp, St&ar, froniidon, 'Ui wine andgrocerieu ;: ;aletn, Bker, from Liverpool,. witfi eoal.;'4Stalled the AluidonG.: ceror' Lkndon, with sundries;: ;Two Rrothwsj'@ Whe~atn-;- Pylade', Eiot; Har'tinny,;;: Fisbley; ::Iiiveiy Peggy:-(flth add tie JAne, Redman,for eathly Newpot;agd llford; -Tw Br.otherAs, lawces,fos Lysixowjvithbinehol V pirI-ihzure;vi etsey, Per-wIliti; iIudstry, ModA - ~tbi ,Al~t,,'enniugs, for.:IP1~iOntI, StIth Ltu .c*ar An'l? Hawkinss foirouck , + iii ballasto I _______~ ~ ~ ~~~Ai
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Bleed through & shine through
General description Effects on OCRing
When the printing ink was not dry, the letters of the one page also appear on the other page. Also, if a paper is relatively thin the ink of the other side of the page may shine through.
Effects are high, since it is the same ink (though lighter) and the shaping of characters is directly disturbed.
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Binarisation
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Annotations in the text
General description Effects on OCRing
All notes, lines, drawings created byusers, but also stamps, tapes etc. usedwithin libraries.
Effects are high, since both segmentationas well as the recognition process itself isdisturbed.
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Improved binarisation
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Original State of the Art IMPACT
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Warping of paper
General description Effects on OCRing
Due to humidity the single page of an old book is very rarely really flat, in contrast it is warped. Even with putting the paper against a glass plate the warping will not disappear.
Partly a relatively high effect, especially if it is connected with bad printing (e.g. characters not aligned on the baseline of a line).
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Border removal
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Geometric correction I
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Geometric correction II
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Gothic typeface
General description Effects on OCRing
Historic fonts, obsolete characterssuch as the long s
Effects are high since such fonts and characters are often not recognised
correctly.
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Improved recognition
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Complex layout
Effects on OCRing
Effects are high since text is not ordered in the right way
General description
Due to difficult layouts, pages can be segmented incorrectly
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Segmentation
Blocks/Regions Words Glyphs
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Functional extension parser
Recognition of the structure of book pages– Print space– Standard font of the
main text– Page numbers
Enrichment of OCR results with structural information
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Bad printing: blurred, broken, faded characters
General description Effects on OCRing
According to the printing technology usedletters may be blurred, broken or dotted.
Effects are high since characters are broken or bound together.
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Cooperative correction
Integrated web-based system for cooperative correction of OCR results
Character/Word/Page mode
Collaboratively correct OCR errors and use results for improving OCR
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Word spotting
Alternative technique for indexing historical documents
After word segmentation relevant words are detected and highlighted
Key words can be e.g. person and location names
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Historical language
Historical variants of the Dutch word ‘wereld’ (world):
werelt weerelt wereld weerelds wereldt werelden weereld werrelts waerelds weerlyt wereldts vveerelts waereld weerelden waerelden weerlt werlt werelds sweerels zwerlys swarels swerelts werelts swerrels weirelts tsweerelds werret vverelt werlts werrelt worreld werlden wareld weirelt weireld waerelt werreld werld vvereld weerelts werlde tswerels werreldts weereldt wereldje waereldje weurlt wald weëled
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Historical dictionariesOCR:
Lexica for German, Dutch, English, French, Spanish, Polish, Bulgarian and Czech
Generic tools for building historical lexica
FineReader with built in standard Dutchstandard Dutch dictionary werreid
FineReader with IMPACT dictionary of historical Dutch werreld
RETRIEVAL:
Key in ‘wereld’ and find ‘werreld’
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Linguistic post-correction
The colors indicate different types of analysis results, like a word being found in the historical or hypothetical dictionary, or a supposed OCR error, etc.
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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IMPACT: Interoperability framework
Interaction, Modularisation, Evaluation
18/08/2010 - IFLA satellite meeting, Uppsala
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands.
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Thank you!
http://www.impact–project.eu/
impact@kb.nl
@impactocr
http://impactocr.wordpress.com/
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