Ask HN: Open source OCR library?

#1

Post by whbv » Thu, Jun 25, 2015, 3:25 AM UTC

Does anyone have a recommendation for a good character recognition library? I'm trying to pull text out of images. I tried ocrad.js but haven't had much success with it.

Re: Ask HN: Open source OCR library?

#2

Post by byoung2 » Thu, Jun 25, 2015, 3:29 AM UTC

https://code.google.com/p/tesseract-ocr/ is pretty good

Re: Ask HN: Open source OCR library?

#3

Post by t0 » Thu, Jun 25, 2015, 4:03 AM UTC

The accuracy of GOCR is very high and it doesn't require any learning.

http://manpages.ubuntu.com/manpages/dapper/man1/gocr.1.html

Re: Ask HN: Open source OCR library?

#4

Post by [deleted] » Thu, Jun 25, 2015, 4:10 AM UTC

[deleted]

Re: Ask HN: Open source OCR library?

#5

Post by sandGorgon » Thu, Jun 25, 2015, 4:10 AM UTC

http://www.danvk.org/2015/01/11/training-an-ocropus-ocr-mode...

Re: Ask HN: Open source OCR library?

#6

Post by stevewepay » Thu, Jun 25, 2015, 4:11 AM UTC

I used Tesseract and OpenCV to process Words With Friends tiles.

Re: Ask HN: Open source OCR library?

#7

Post by yoda_sl » Thu, Jun 25, 2015, 4:19 AM UTC

byoung2 wrote: post #2

https://code.google.com/p/tesseract-ocr/ is pretty good

Tesseract is quite good and can get some really good results if you can train it. I just wish there was a more UI friendly way for generating the training file; for the project where I had to use it I ended up paying a freelancer with some strong knowledge of Tesseract training. Really happy with the results for my iOS app (universal app)

Re: Ask HN: Open source OCR library?

#8

Post by Omnipresent » Thu, Jun 25, 2015, 4:34 AM UTC

I've used tesseract to great affect. I don't know how your images are but if only part of the image has text in it, you should only send that part to the OCR engine. If you send the entire image and only a portion of it has text in it, chances of the OCR extracting text are slim. There are pre-processing techniques [1] you can use to crop out the part of the image that has text

[1]: https://en.wikipedia.org/?title=Hough_transform

Re: Ask HN: Open source OCR library?

#9

Post by kregasaurusrex » Thu, Jun 25, 2015, 4:35 AM UTC

stevewepay wrote: post #6

I used Tesseract and OpenCV to process Words With Friends tiles.

I think this is the best solution, though a bit daunting without experience in either to approach. But you'll get access to processing all of your information in a low level language very quickly.

Re: Ask HN: Open source OCR library?

#10

Post by [deleted] » Thu, Jun 25, 2015, 4:50 AM UTC

Omnipresent wrote: post #8

I've used tesseract to great affect. I don't know how your images are but if only part of the image has text in it, you should only send that part to the OCR engine. If you send the entire image and only a portion of it has text in it, chances of the OCR extracting text are slim. There are pre-processing techniques [1] you can use to crop out the part of the image that has text [1]: https://en.wikipedia.org/?title=Ho…

[deleted]