Signal Processing Stack Exchange
Signal Processing Stack Exchange

Questions tagged [ocr]

Optical Character Recognition is mechanical or electronic translation of images of handwritten, typewritten or printed text into text data (a sequence of codes used to represent characters in the computer).

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Filtering kinda "half-toned" image for OCR processing

I have a scanned PDF material to which I want to add hidden text layer, so I could index the document. I used ghostscript black and white tiff output device (tiffg4) to extract pages as tiff images, and here is example of what they look…
zetah
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Suggested Preprocessing methods for OCR on Circular Images

Hello this is my sample image I am going to do real time character detection on images like that. I've tried SURF, SIFT, MSER and template matching on original image without any preprocessing. I can detect characters but when the image changes this…
Anar Bayramov
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Nutrition facts label OCR

My team is working on a program that can read nutrition facts labels using OCR, much like NutriScanner (though by its reviews it doesn't seem like it works particularly well). I've seen other questions noting that it'd be a good idea to straighten…
Ian Kim
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Text recognition for Android app

I´d like to use some OCR algorithm (Image to Text) into an Android app (Java). I have previously used several algorithms but for a PC (Matlab) app. Which library or algorithm should I use? Computational cost and response time are important issues.
Luis Andrés García
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Document image vanishing point detection and evaluation

It is a natural idea to substitute our scanner with mobile phone, and perform OCR with the phone at the same time. If this can come true, two problems must be tackled: one is related to document image binarization, and the other is related to…
feelfree
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Sharpen Defocused Image (Deconvolution / Image Restoration)

Using OCR, I want to extract text from product packages using Google Glass. However, because of the fixed focus of the camera the package pictures are blurred. Is there a way to sharpen the image? Currently I use unsharp masking to enlarge the…
Marius Herzog
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Feature Detection on a Circular Metal Surface for Character Recognition

Hello I'm trying to recognize characters on the circular metal surface. Without any preprocessing I could match cropped features with original image. I've actually cropped 2 characters together to increase interested points on a template.…
Anar Bayramov
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Licence plate detection with different backgrounds

I just studied the Algorithm of ANPR (Automatic Number Plate Recognition) from the chp 5 of book Packtpub.Mastering.OpenCV.with.Practical.Computer.Vision.Projects in which they detect the vehicle licence plate , but their are some restriction in…
ARG
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Smoothing "font characters" outlines in bitmap image

Adobe Acrobat has this as a feature called ClearScan. While doing OCR it allows image enhancement, by smoothing irregularities on font outlines. For example, this source: turns to this: Are there other tools with such feature, or public algorithms…
zetah
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Recognizing hand-written archaeological signs

I have 75 images of handwritten signs from which I extracted 7 Hu moments and solidity features. How can I find similarities among them to train a classifier and predict the value? I thought SVM was a good choice, but I don't have a target vector…
postgres
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Line tracing folowing a path of an almost connected components

say we have a binary image like the one in below i would like to extract each black line, even if it's not almost connected i have marked here in red, example of lines that correspond to those to be extracted **the purpose here is to extract lines a…
Brain Marker
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Match (OCR?) a digital image of a product label to similar

Excuse my ignorance... Given a digital image of a label I'd like to Requirement: Match it to the closest pre-existing image in a datastore Optional: OCR it, if possible (only necessary if step 1 fails) I'm a programmer but not an engineer. I have…
Meltemi
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How to Clean Black and White Images Which Are Results of Edge Detection

I want to extract text from some images with messy backgrounds. First step was switching to gray scale, applying an edge detection algorithm, and then cleaning up a little bit. Here's an example of the result: I want to use the tesseract OCR to…
Robin
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What is the algorithm behind OCR?

I'm curious about the algorithm and basic principles behind Optical Character Recognition. Can anyone explain: The most basic OCR algorithm that can be fairly easily implemented from scratch? Or the common denominator between different OCR…
Geerten
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Compare feature vectors of an image in MATLAB

I am working on OCR. I have extracted features of 26 alphabets, and I want to compare them with an experimental character feature. I have tried using Euclidean distance and correlation functions, but I am not getting good efficiency. What are some…
SKK
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