Questions tagged [ocr]

Optical Character Recognition, usually abbreviated to OCR, is the mechanical or electronic translation of scanned images of handwritten, typewritten or printed text into machine-encoded text. The following topics, although some being distinct fields of application, are also commonly referred to as OCR: Handwritten Text Recognition (HTR), Optical Word Recognition (OWR), Intelligent Character Recognition (ICR), Intelligent Word Recognition (IWR).

Optical character recognition, usually abbreviated to OCR, is the mechanical or electronic translation of scanned images of handwritten, typewritten or printed text into machine-encoded text. It is widely used to convert books and documents into electronic files, to computerize a record-keeping system in an office, or to publish the text on a website.

OCR @Wikipedia

Frequently-asked questions:

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Most accurate open-source OCR for Japanese?

From your experience, what is the most accurate open-source Optical Character Recognition (OCR) library/software to read Japanese text? I just tried nhocr, its mistake rate is over 2% even on an extremely clean high-definition document.
Nicolas Raoul
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Detecting the National ID card and getting the details

I am trying to detect the National ID of the below type and get the details of it, For example the location of the signature should be found at the top right corner of the persons image, in this case "BC". I need to do this application in iphone. I…
2vision2
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Best way to recognize characters in screenshot?

What would you recommend for recognizing all characters from a screenshot? The screenshot is perfectly clear (only black text on a white background), also I can choose any standard font for the text (installed on Windows). I have tried some OCR ways…
Tomek
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Tesseract traineddata not working in Swift 3.0 project using version 4.0

I'm attempting to use Tesseract-OCR-iOS in a new Swift 3.0 project. I'm using Xcode Version 8.1 (8B62). CocoaPods is version 1.1.1. When I attempt to use tesseract.recognize(), my app crashes and I get the following output in the…
Adrian
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How to use Microsoft OCR Library ( Microsoft.Windows.Ocr ) in an ASP.Net MVC4 Web API Project?

TL;DR: Does anyone know of a way to reference Microsoft.Windows.Ocr (/ WindowsPreview.Media.Ocr.dll ) Assembly on a server-side ASP.Net Web application like MV4 Web API and make use of the OCR Functionality in that assembly to take a photo image as…
Shiva
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How to preserve document structure in tesseract

I am using tesseract ocr to extract text from an image. Preserving the structure of the document is very important to me. Currently tesseract does not preserve the structure, infact it changes the order of text. My input is the image below. and the…
Sar009
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Open source OCR tool available in the market

Is there any open source OCR library written in .NET, or written in any language but can be used in an ASP.NET application? Or is there any open source OCR API available in the market for image to tabular formats ?
ri2008xyz
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Google ML Kit: Waiting for the text recognition model to be downloaded

[mlkit] I am implementing the "On-device text recognition" from the Google Machine Learning Kit for android. I followed this guide but every time try to detect text I get the exception "Waiting for the text recognition model to be downloaded. Please…
M.Paunov
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Crop an image using multiple points and flexible size?

I want to make a an application like a cam scanner for cropping a document. But I need same functionality like my two images.. First Images shown image captured by camera.. Second image recognize a captured image part like this.. I research more…
Roadies
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Why Tesseract OCR library (iOS) cannot recognize text at all?

I'm trying to use Tesseract OCR library in my iOS application. I downloaded tesseract-ios library from github and when I tried to recognize a simple text image I got garbage instead. Here is an image of what I tried to recognize: I got unreadable…
MainstreamDeveloper00
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Tesseract does not recognize single characters

How to represent: Create new image with paint (any size) Add letter A to this image Try to recognize -> tesseract will not find any letters Copy-paste this letter 5-6 times to this image Try to recognize -> tesseract will find all the letters Why?
artem
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OCR error correction algorithms

I'm working on digitizing a large collection of scanned documents, working with Tesseract 3 as my OCR engine. The quality of its output is mediocre, as it often produces both garbage characters before and after the actual text, and misspellings…
Andrew Pendleton
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How can I use the Keras OCR example?

I found examples/image_ocr.py which seems to for OCR. Hence it should be possible to give the model an image and receive text. However, I have no idea how to do so. How do I feed the model with a new image? Which kind of preprocessing is necessary?…
Martin Thoma
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Tesseract receipt scanning advice needed

I have struggled off and on again with Tesseract for various OCR projects and I found a use case today which I thought would be a slam dunk for it but after many hours I am still coming away unsatisfied. I wanted to pose the problem here and see…
Jim Sanders
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Improving OCR performance on multi-paragraph scans

I'm working on a project that involves extracting text scientific papers stored in PDF format. For most papers, this is accomplished quite easily using PDFMiner, but some older papers store their text as large images. In essence, a paper is…
Louis Thibault
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