ocrmypdf(1)

NAME

   ocrmypdf - add an OCR text layer to PDF files

DESCRIPTION

   usage:   ocrmypdf   [-h]   [--verbose   [VERBOSE]]   [--version]   [-n]
   [--flowchart FILE]

          [-l  LANGUAGE]   [-j   N]   [--image-dpi   DPI]   [--output-type
          {pdfa,pdf}]   [--title   TITLE]   [--author  AUTHOR]  [--subject
          SUBJECT] [--keywords KEYWORDS] [-r]  [--remove-background]  [-d]
          [-c]  [-i]  [--oversample  DPI]  [-f]  [-s] [--skip-big MPixels]
          [--tesseract-config    CFG]    [--tesseract-pagesegmode     PSM]
          [--pdf-renderer    {auto,tesseract,hocr}]   [--tesseract-timeout
          SECONDS]   [--rotate-pages-threshold   CONFIDENCE]   [-k]   [-g]
          input_file output_file

   Generates a searchable PDF or PDF/A from a regular PDF.

   OCRmyPDF  rasterizes  each  page  of the input PDF, optionally corrects
   page rotation and performs image processing,  runs  the  Tesseract  OCR
   engine on the image, and then creates a PDF from the OCR information.

   positional arguments:
   input_file
          PDF  file containing the images to be OCRed (or '-' to read from
          standard input)

   output_file
          output searchable PDF file (or '-' to write to standard output)

   optional arguments:
   -h, --help
          show this help message and exit

   -l LANGUAGE, --language LANGUAGE
          Language(s) of the file to be OCRed (see tesseract  --list-langs
          for  all  language  packs  installed in your system). To specify
          multiple languages, join them with '+' or  issue  this  argument
          once for each language.

   -j N, --jobs N
          Use up to N CPU cores simultaneously (default: use all)

   --image-dpi DPI
          for input image instead of PDF, use this DPI instead of file's

   --output-type {pdfa,pdf}
          Choose output type. 'pdfa' creates a PDF/A-2b compliant file for
          long term archiving (default, recommended) but may not  suitable
          for  users  who  want  their file altered as little as possible.
          'pdfa' also has problems with full Unicode text. 'pdf'  attempts
          to preserve file contents as much as possible.

   Common options:
   --verbose [VERBOSE], -v [VERBOSE]
          Print more verbose messages for each additional verbose level.

   --version
          show program's version number and exit

   pipeline arguments:
   -n, --just_print
          Don't actually run any commands; just print the pipeline.

   --flowchart FILE
          Don't run any commands; just print pipeline as a flowchart.

   Metadata options:
          Set   output  PDF/A  metadata  (default:  use  input  document's
          metadata)

   --title TITLE
          set document title (place multiple words in quotes)

   --author AUTHOR
          set document author

   --subject SUBJECT
          set document subject description

   --keywords KEYWORDS
          set document keywords

   Image preprocessing options:
          Options to improve the quality of the final PDF and OCR

   -r, --rotate-pages
          automatically rotate pages based on detected text orientation

   --remove-background
          attempt to remove background from gray or color  pages,  setting
          it to white

   -d, --deskew
          deskew each page before performing OCR

   -c, --clean
          clean  pages  from scanning artifacts before performing OCR, and
          send the cleaned page to OCR, but do  not  include  the  cleaned
          page in the output

   -i, --clean-final
          clean  page  as  above, and incorporate the cleaned image in the
          final PDF

   --oversample DPI
          oversample images to at least the specified DPI, to improve  OCR
          results slightly

   OCR options:
          Control how OCR is applied

   -f, --force-ocr
          rasterize  any  fonts or vector objects on each page, apply OCR,
          and save the rastered output (this rewrites the PDF)

   -s, --skip-text
          skip OCR on any pages that already contain text, but include the
          page  in  final  output;  useful  for PDFs that contain a mix of
          images, text pages, and/or previously OCRed pages

   --skip-big MPixels
          skip  OCR  on  pages  larger  than  the  specified   amount   of
          megapixels, but include skipped pages in final output

   Advanced:
          Advanced options for power users

   --tesseract-config CFG
          additional Tesseract configuration files

   --tesseract-pagesegmode PSM
          set Tesseract page segmentation mode (see tesseract --help)

   --pdf-renderer {auto,tesseract,hocr}
          choose  OCR PDF renderer - the default option is to let OCRmyPDF
          choose. The 'tesseract' PDF renderer is more accurate and does a
          better  job  and document structure such as recognizing columns.
          It also does a better job on non-Latin  languages.  However,  it
          does  not  work  as  well  when  older  versions of Tesseract or
          Ghostscript are installed, and some combinations of arguments to
          do not work with --pdf-renderer tesseract.

   --tesseract-timeout SECONDS
          give up on OCR after the timeout, but copy the preprocessed page
          into the final output

   --rotate-pages-threshold CONFIDENCE
          only rotate pages when confidence is above this value (arbitrary
          units reported by tesseract)

   Debugging:
          Arguments to help with troubleshooting and debugging

   -k, --keep-temporary-files
          keep temporary files (helpful for debugging)

   -g, --debug-rendering
          render each page twice with debug information on second page

   OCRmyPDF attempts to keep the output file at about the same size.  If a
   file contains losslessly compressed images, and  output  file  will  be
   losslessly compressed as well.

   PDF  is  a  page  description  file  that attempts to preserve a layout
   exactly.  A PDF can contain vector objects (such as text or lines)  and
   raster  objects (images).  A page might have multiple images.  OCRmyPDF
   is prepared to deal with the wide variety of PDFs  that  exist  in  the
   wild.

   When  a  PDF  page  contains  text,  OCRmyPDF assumes that the page has
   already been OCRed or is a "born  digital"  page  that  should  not  be
   OCRed.   The default behavior is to exit in this case without producing
   a file.  You can use the option --skip-text to ignore pages with  text,
   or  --force-ocr  to  rasterize  all  objects on the page and produce an
   image-only PDF as output.

          ocrmypdf --skip-text file_with_some_text_pages.pdf output.pdf

          ocrmypdf --force-ocr word_document.pdf output.pdf

   If you are concerned about long-term archiving of PDFs, use the default
   option  --output-type  pdfa  which  converts  the PDF to a standardized
   PDF/A-2b.  This  converts  images  to  sRGB  colorspace,  removes  some
   features  from  the  PDF  such  as  Javascript or forms. If you want to
   minimize the number of changes made to your PDF, use --output-type pdf.

   If OCRmyPDF is given an image file as input, it will attempt to convert
   the  image  to  a  PDF  before  processing.   For more control over the
   conversion of images to PDF, use the Python package  img2pdf  or  other
   image to PDF software.

   For  example,  this  command  uses  img2pdf  to  convert all .png files
   beginning with the 'page' prefix  to  a  PDF,  fitting  each  image  on
   A4-sized  paper,  and  sending  the  result to OCRmyPDF through a pipe.
   img2pdf is a dependency of ocrmypdf so it is already installed.

          img2pdf --pagesize A4 page*.png | ocrmypdf - myfile.pdf

   HTML documentation is located at:
          /usr/share/doc/ocrmypdf/html/index.html

   after installing the ocrmypdf-doc package.

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