1. Click to edit document name
IMPACT: Challenges
and solutions
Hildelies Balk, IMPACT
Project Director, KB
National Library of the
Netherlands

2. IMPACT: Challenges and solutions
Overview of this presentation
• Challenges in digitisation of historical full text
• IMPACT objectives
• Approach
• Achievements
• Better, Faster, Cheaper

3. IMPACT: Challenges and solutions
The content
• Shared vision in
Europe: all cultural
heritage available in
digital form in this
decade
• Billions of pages of
historical (pre-1900)
text in libraries in
Europe
• Users expect full text
to search, tag and re-
use
• Just image and
metadata not enough
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4. IMPACT: Challenges and solutions
The full text
VVt Venetien den 1.Junij, Anno 1618.
DJgn i f paffato te S' aö'Jifeert mo?üen/bah
.)etgi'uotbciraetail)i.r/JtmelchontDecht
te / sbnbe bele btr felbrr geiufttceert baer bnber
eeniglje jprant o^fen/bie ftcb .met beSpaenfcbeu
enbeeemgljen bifet Cbeiiupcen berbonbru befe

5. IMPACT: Challenges and solutions
Challenges to OCR
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6. IMPACT: Challenges and solutions
Language challenges
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

7. IMPACT: Challenges and solutions
Answering the challenges: IMPACT
IMPACT – Improving Access to Text (2008-2011)
• Large-scale integrating research project
• Consortium of 26 partners
• Coordinated by the National Library of the Netherlands (KB)
• Co-funded by EU (FP7 ICT Work Programme)
Objectives:
Significantly improve mass digitisation of historical printed text by:
• Innovating OCR software and language technology
• Sharing expertise and building capacity across Europe
• Providing facilities for future research and development
Making text digitisation better, faster, cheaper!

8. IMPACT: Challenges and solutions
IMPACT Approach
• Content holders, researchers and industry work together to find solutions
• Based on real life problems in digitisation
• Tackle each step in the digitisation workflow from scan to full text
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OCR Post correction and Enrichment
ABBY FR CONCERT IBM
Image enhancement:
Preparation and IBM Adaptive Error Profiler LMU
Binarisation
scanning: Dictonaries/interface
noise removal Language resources 9 partners
guidelines and Segmentation and
geometrical defects LMU,INL Platform for document
case studies Document analysis
correction Experimental engines understanding based on OCR UIBK
All partners NSCR,USAL, ABBYY USAL,NCSR,ABBYY
USAL,NCSR,UIBK
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9. IMPACT: Challenges and solutions
IMPACT Approach - continued
• Tools to be coupled in Interoperability Framework
• Tested with Evaluation tools and metrics
• Against representative set of test data with Ground Truth
• Basis for further research and development
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10. IMPACT: Challenges and solutions
Achievements: summary
On market: Improved ABBYY FR Engine 10, Recogition Server 3, Cloud OCR
In use in productive environment:
• Service for document structure recognition
• Dutch and Slovene dictionary
• Alethia
Ready for testing in productive environment:
• Adaptive OCR engine
• Tools for OCR correction with volunteer involvement
• Computer lexica for nine languages
• Digitisation Framework with evaluation tools and dataset
• Knowledge bank with guidelines and learning resources
For future development:
• Novel Approaches to preprocessing, OCR and post correction
• New language resources with Tools for lexicon building
impact Centre of Competence for digitisation
• Added value: Unique network bringing together experts from different communities

11. IMPACT: Challenges and solutions
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12. IMPACT: Challenges and solutions
Better: rule set for extracting table of
content entries from historical books
outperforms best results of the
Results: better & faster INEX competition 2011
• All tools evaluated in different test scenarios on IMPACT dataset
• All individual tools show improvement on state of the art Faster: postcorrection with
• Some examples of results – there is more! Error Profiler up to 2,7 times
faster than without
Better: Tested on
Better: hybrid line Better: recognition of
38718 randomly
segmentation on 2.700 old fonts FR9→FR10 Faster: CONCERT
selected historical
text lines SOA 90,9 % → 25% reduction of errors increases correction
images and
IMPACT 98,8% speed up to 40%
achieved a success
of 98.93% (SoA up to Better, faster:Adaptive
97.3% OCR on small testset
halves FOM (post Better: language
processing level required) resources show
improvement for all 9
languages
OCR
ABBY FR Post correction and Enrichment
Image enhancement:
IBM Adaptive CONCERT IBM
Binarisation Segmentation and
Noise removal Dictonaries / interface Error Profiler LMU
Document analysis
Geometrical defects LMU,INL Language resources 9 partners
USAL, NCSR, ABBYY
correction Experimental OCR engines Document Understanding Platform
NSCR, USAL, ABBYY USAL, NCSR, UIBK UIBK
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13. IMPACT: Challenges and solutions
Results: cheaper
Industry in IMPACT:
• ABBYY FR Historic Fonts Module more than 10 times cheaper; more flexible rates
overall
• IBM Adaptive OCR and CONCERT: flexible rates
Research in IMPACT:
• Key Language resources free
• All tools by research partners free for research and free / low rates on non
commercial use (individual licensing required), subject
to volume, kind of use and material, support etc.
Framework:
• Digitisation Framework free and open source
• Open source wrapper to plug in other tools
• Fruitful contacts with new tool providers

14. IMPACT: Challenges and solutions
Benefits
For the digital library
• Rough average of all tests by developers on IMPACT dataset
indicates consistent improvement of up to 20%
• Better access, faster and cheaper production
For the end user
• main interest: retrieval = words searched and found correctly
• Preliminary results of ABBYY FR 10 with Dutch lexicon on difficult
material (Dutch 17th century newspaper): 15% increase of words
found
 For 1 M words this means 150 K more words found
...and this is just the beginning!

15. IMPACT: Challenges and solutions