utiliser tesseract (cf infra)

requiert tesseract:

sudo apt-get install tesseract-ocr tesseract-ocr-fra

#!/usr/bin/bash
# pdf_ocr2txt
ls *.pdf | while read i
do
	echo "converting pdf file: " $i " to tif file " $i.tif
	convert -density 400 -depth 8 $i $i.tif
	echo "-----"
	echo "Generating txt file " $i.txt
	tesseract $i.tif $i.txt -l fra
done

http://doc.ubuntu-fr.org/tesseract-ocr

 convert -density 300 file.pdf -depth 8 file.tiff  
 tesseract file.tiff file.txt -l fra
 

#!/bin/sh
echo "convertit un document pdf et réalise une reconnaissance optique de caractères"
echo "entrer le nom du fichier"
ls *.pdf
read fichier
echo "combien de pages?"
read npages
PAGES=$npages # set to the number of pages in the PDF
SOURCE=$fichier # set to the file name of the PDF
OUTPUT=$fichier.txt # set to the final output file
RESOLUTION=600 # set to the resolution the scanner used (the higher, the better)

#xpdf-pdfinfo pamphlet-low.pdf | grep Pages: | awk '{print $2}' | tail -n 1

#touch $OUTPUT
for i in `seq 1 $PAGES`; do
    convert -density $RESOLUTION -depth 8 $SOURCE\[$(($i - 1 ))\] page$i.png
##    tesseract page$i.tif >> $OUTPUT
    tesseract page$i.png $OUTPUT$i -l fra
done

http://www.tristancollins.me/computing/ocr-using-tesseract-on-multipage-pdfs/

http://code.google.com/p/tesseract-ocr/

marche nickel!

• https://pyimagesearch.com/2020/08/03/tesseract-ocr-for-non-english-languages/
• https://github.com/tesseract-ocr/tessdata/blob/main/rus.traineddata

  mv rus.traineddata /usr/share/tesseract-ocr/4.00/tessdata/

Ou encore plus simple

  sudo apt-get install tesseract-ocr-rus