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How can I extract text from images?

I am not talking about scanned files, but garden variety images, such as when you take a high-def picture of a blackboard at class, and it is nicely handwritten; or when you photograph a page from a recipe book and want the recipe in text format.

Any free and open software for that?

I tried tesseract, and the results were awful.

  • I need a OCR that supports Bengali and English simultaneously. – alhelal May 8 '17 at 9:45
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The act of extracting text from images is called OCR and Ubuntu has a wiki page dedicated to OCR. From that page:

Available OCR tools

The Ubuntu Universe repositories contain the following OCR tools:

  1. gocr - A command line OCR
  2. fuzzyocr - spamassassin plugin to check image attachments
  3. libhocr0 - Hebrew OCR
  4. ocrad - Optical Character Recognition program
  5. ocrfeeder - Document layout analysis and optical character recognition system
  6. ocropus - document analysis and OCR system
  7. tesseract-ocr

The Ubuntu multiverse respositories also contain:

  1. cuneiform - multi-language OCR system

Some packages are outdated, but unofficial fresh ones can be found in Alex_P PPA (PPA adding code: ppa:alex-p/notesalexp). If you never used a PPA check how to add software from a PPA.

edit: As shown in comment Clara OCR exists too but it got stuk at Hardy and their website has 2009 as last updated.

  • Do you have experience using any of those for the examples I described? I became a bit sceptical to regular ocr tools for them. Number 7 on the list is the one I tried and was plainly terrible. – Strapakowsky Aug 31 '11 at 9:11
  • If I recall, I tried gocr also, with equivalent terrible results. If you tried with success any of those, what syntax did you use? Thanks. – Strapakowsky Aug 31 '11 at 9:13
  • None whatsoever! I never bothered with OCR :D Freshmeat search shows Clara OCR and tesseract-ocr ;) ( freshmeat.net/search/… ) – Rinzwind Aug 31 '11 at 11:16
  • Am I wrong if I say that successful use of OCR requires knowledge of the process and a careful setup to fit the particular image to be scanned? Thus, if I'm right, bad results might be due to the user and not the software. – N.N. Aug 31 '11 at 11:37
  • OCR works best if you know how the image is created and you are very well versed in using the software that you use (the latter being the reason I never got around to using it). – Rinzwind Aug 31 '11 at 11:43
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tesseract-ocr would be the great one compared to all other. For Installation, run command sudo apt-get install tesseract-ocr.

Usage is tesseract filename.jpg output.txt.

Above command will generate output.txt.

You might consider selecting the appropriate language. In that case you will need to install tesseract-ocr-LANG package, where LANG is the three letter ISO 639-2 language code. Right now you have 123 languages on 18.04 repo. Then use for example:

tesseract mySpanishText.jpg output -l spa
  • Hey, so this does works but is not accurate or I would rather say is 80-85% accurate. Like example for this image: pbs.twimg.com/media/DJs6_pcXkAA2VrN.jpg, it messed up $ sign and also most brackets. Square, round, curly, all brackets are a problem, they never get extracted properly. Do you know of any fix? – Milan Chheda Sep 19 '17 at 14:08

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