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This module acts a Toolkit for generating OCR and word coordinate information . At the moment it relies exclusively (stored in an HOCR datastream) that is required for on-page highlighting. The module relies on Tesseract to generate this information.

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Tesseract is an OCR engine that was developed at HP Labs between from 1985 and by Google from 1995. It is currently being developed at Google. Recognized as one of the most accurate open source OCR engines available, Tesseract will read binary, grey, or colour images and output text.

A TIFF reader that will read uncompressed TIFF images is also included. Islandora Book Solution Pack currently uses requires at least Tesseract version 3.2.2, which can be obtained from the project home page. Lower versions are not supported. 

Dependencies

• Islandora
• Tuque
• Tesseract (3.02.02 or later)
• ImageMagic (Optional, Required for OCR preprocessing)
• Islandora Paged Content (Optional)

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In Administration » Islandora » Islandora Utility Modules » OCR Tool (admin/islandora/tools/ocr), configure you can do the following:

• Set the path for Tesseract
• Select languages available for OCR from your Tesseract installation
• Enable/disable Solr Fast Vector Highlighting
• Set Solr field containing OCR text and the maximum number of results to return in a Solr query

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To have Islandora viewers recognize Solr search results and highlight them, one will need to configure Solr to index the HOCR (coordinate data) in a particular fashion.

The field that the HOCR is stored in must have the following attributes: indexed="true" stored="true" termVectors="true" termPositions="true" termOffsets="true"

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