69 lines
2.8 KiB
Markdown
69 lines
2.8 KiB
Markdown
OCRmyPDF
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========
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OCRmyPDF adds an OCR text layer to scanned PDF files, allowing them to be searched
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To get the script usage, call: sh ./OCRmyPDF.sh -h
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Main features
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--------
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- Generates a searchable PDF/A file from a PDF file containing only images
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- Places OCRed text accurately below the image to ease copy / paste
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- Keeps the exact resolution of the original embedded images
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- or if requested oversample the images before OCRing so as to get better results
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- If requested deskews and / or clean the image before performing OCR
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- Validates the generated file against the PDF/A specification using jhove
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- Provides debug mode to enable easy verification of the OCR results
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- Processes several pages in parallel if more than one CPU core is available
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For details: please consult the release notes
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Motivation
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----------
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I searched the web for a free command line tool to OCR PDF files on linux/unix:
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I found many, but none of them were really satisfying.
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- Either they produced PDF files with misplaced text under the image (making copy/paste impossible)
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- Or they did not display correctly some escaped html characters located in the hocr file produced by the OCR engine
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- Or they changed the resolution of the embedded images
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- Or they generated PDF file having a ridiculous big size
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- Or they crashed when trying to OCR some of my PDF files
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- Or they did not produce valid PDF files (even though they were readable with my current PDF reader)
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- On top of that none of them produced PDF/A files (format dedicated for long time storage / archiving)
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... so I decided to develop my own tool (using various existing scripts as an inspiration)
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Install
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-------
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Download OCRmyPDF here: https://github.com/fritz-hh/OCRmyPDF/releases
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Copy the file in onto your linux/unix machine and extract it.
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Run: "sh ./OCRmyPDF.sh -h" to get the script usage
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If not yet installed, the script will notify you about dependencies that need to be installed.
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The script requires specific versions of the dependencies. Older version than the ones mentioned in the release notes are likely not to be compatible to OCRmyPDF.
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Support
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-------
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In case you detect an issue, please:
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- Check if your issue is already known
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- If no problem report exists on github, please create one here: https://github.com/fritz-hh/OCRmyPDF/issues
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- Describe your problem thoroughly
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- Append the console output of the script when running the debug mode (-g option)
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- If possible provide your input PDF file as well as the content of the temporary folder (using a file sharing service like www.file-upload.net)
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Press & Media
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-------------
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- c't 1-2014, page 59: Detailed presentation of OCRmyPDF v1.0 in the leading german IT magazine c't (http://www.heise.de/ct/inhalt/2014/1/58/)
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Disclaimer
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----------
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The software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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