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Ask HN: Open source OCR library?

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Re: Ask HN: Open source OCR library?

#101

Post by totalcookie »

zo1 wrote: post #82
totalcookie wrote: post #73

Earlier quoted context omitted.

If there is no opensource/free software with the same quality, what then? What are you using as an OCR server side system on Linux? I'm sure not good enough to write my own OCR better than Abbyy.

As the others in the thread have mentioned. Constrain your problem as a computer-vision one to segment nice pieces of work for Tesseract. Along with some nice training data, and possibly human validation if that's feasible. All do-able within Linux.

As the parent of this comment thread mentions, Tesseract is not very great for mass usage due to the error rate with Abbyy much better. I would be interested in experience not opinion.

Re: Ask HN: Open source OCR library?

#102

Post by hbornfree »

netheril96 wrote: post #99
hbornfree wrote: post #17

As others pointed out, Tesseract with OpenCV (for identifying and cropping the text region) is quite effective. On top of that, Tesseract is fully trainable with custom fonts. In our use case, we've mostly had to deal with handwritten text and that's where none of them really did well. Your next best bet would be to use HoG(Histogram of oriented gradients) along with SVMs. OpenCV has really good implementations of bo…

In my experience, CNNs offer the best performance. It is also easy to treat as a black box with many tunable parameters. But the existing frameworks are mostly bad as an engineering product. Caffe, for example, calls `exit` every time an error occurs, including recoverable ones like files which do not exist.

Yes, even we found Caffe to be overwhelming. This library seems promising considering there are no dependencies and is quite portable to Android or iOS. https://github.com/nyanp/tiny-cnn

Re: Ask HN: Open source OCR library?

#104

Post by mfalcon »

kargo wrote: post #32

Does it have to be open-source? If free, but not trainable and restricted to Windows apps/phone is good enough, then I recommend the Microsoft OCR library. It gives you very, VERY good results out of the box. An excellent piece of work from Microsoft Research. To test it, see for example https://ocr.a9t9.com/ which uses Microsoft OCR inside. And for comparison, an OCR application with Tesseract inside: It has a drama…

I tried your app with this image: http://cdn.swapweb.com.ar/estilo-web.net/publis/dell_inspiro... and the results were impressive!.

Much much better than what I can get with tesseract. Would love to have it as an API service.

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