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Questions tagged [omr]

OMR (Optical Mark Recognition or optical mark reading) is the process of capturing human-marked data from document forms such as surveys and tests.

OMR (Optical Mark Recognition or optical mark reading) is the process of capturing human-marked data from document forms such as surveys and tests.

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Wikipedia

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Checkbox detection is ticked or not opencv

I have been trying to detect the checkboxes. Though I was able to detect the checkboxes in images but I can't detect the checkbox is checked or not. If checkbox is checked then the checkbox is bounded by some colour and if checkbox is unchecked…
Nithishkumar
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Comparing Bitmap objects with different colors

I have a Bitmap object of a hand-written survey (see survey image below) which contains various checkboxes. I am using an algorithm to compare a Bitmap of a blank, unmarked checkbox against a Bitmap of the same checkbox (which may or may not be…
craig2020
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Access violation on calling j9port_startup_library

I have build openj9 for Windows using these instructions: https://github.com/eclipse/openj9/blob/master/buildenv/Build_Instructions_V8.md#windows When I try the following code (Visual Studio 2017): J9PortLibraryVersion…
Remko
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Display 2-D GIS polygon in 3-D street-level view

I would like to drape some 2-D GIS polygon into a ‘3-D’ street level? As a a picture is worth a thousand words, please check this: So I have the azimuth angle, the view angle and the position where the image was taken along with the field limit in…
Wraf
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Optical Mark Recognition using C#

This is a function which determines if a point is within the boundary of the image and checks if it overlaps with other circle. If it returns true then i check the threshold of the circle filled black and later save the point which is filled more…
Zimad
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Python retrieving the (x,y) coordinates of top left corner of black rectangle on JPEG image

BACKGROUND: I am trying to create a software to mark the answer papers automatically. The answer paper format is fixed and is as below: PROBLEM: In order to detect the box that user cross (A,B,C?), I need to crop or do a perspective transform based…
Chris Aung
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What is the proper way to test if checkbox is ticked on scanned document?

Let's assume, that we're scanning test-like documents with checkboxes / empty circles (for signing / striking / ticking). What would be the proper way, to check, if already cropped checkbox/circle is checked/signed/striked/ticked? In case we'll…
mrówa
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How to extract pencil markings from the below sheet using opencv in python

I am unable to extract the pencil markings provided in the below picture using opencv. I am unsure if it's because of the kernel size (though I tried playing with the size), but the extraction is not particular. This is based out of MCQ scanner and…
user5073846
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Hough Gradient Method misses some circles

Consider the images below: As can be seen, many circles are not detected. I have already played with param1 and param2 (cv2.HoughCircles) in the code below: import cv2 import numpy as np from PIL import Image # Load the image and downscale it img…
PaulS
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Differentiating between circle and letter/number contours in OpenCV python?

Using the method outlined in this website to isolate the circular contours: https://www.authentise.com/post/detecting-circular-shapes-using-contours, I was able to achieve the following contours outlined in blue in the photo. However, the method is…
Joshua Yang
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OpenCV OMR Sheet - Detect Marked Answers in Python - Getting Proper Binarization

While solving an OMR problem I am not completely able to detect all the marked answers correctly. Here is my input sheet. Input Image my code to Binarize the image. import cv2 image = cv2.imread('input.png') img =…
rnative
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OMR BubbleSheet Test Recognization

I'm handling my last homework for the university in Spain (Business Adminstration), and I decided create a system that the Teacher insert the Exam correct answer, then download a model to give to the students do the exam, and after recieve the…
Paulo Ventura
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Extract data in Checkbox region

I want to extract the data after the checkbox. For example in the image for checkbox there is tickmark for NO we want to extract NO. are there any OMR tools or any computer vision algorithms for this.
Venkata Sai
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OpenCV find the contours of box based on 4 square points around

Is there a way to get content inside the box (dashed red rectangle I've noted) based on 4 small squares around it? My code: # Read and resize image img_input = cv2.imread(args.pop('image'), ) img_input_height, img_input_width, _ =…
dphans
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Fast and quick pixel matching algorithm

I am stuck in a pixel matching algorithm for finding symbols in an image. I have two images of symbols that I intend to find in an image that has big resolution. Instead of a pixel by pixel matching algorithm, is there a fast algorithm that gives…
Computer User
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