jansenfelipe/omr

Optical Mark Recognition from PHP

Optical Mark Recognition with PHP

, _(*1)

This is an open source library written in PHP for recognition markings on questionnaires scans, _(*2)

See: https://en.wikipedia.org/wiki/Optical_mark_recognition, _(*3)

, _(*4)

How to use

Add library:, _(*5)

$ composer require jansenfelipe/omr

Instantiate the Scanner class responsible for reading the image and enter its path, _(*6)

/*
 * Setup scanner
 */
$scanner = new ImagickScanner();
$scanner->setImagePath($imagePath);

You will need to scan a blank form and create the Target Mapping File to be able to use the library., _(*7)

After creating the map.json file, enter its path:, _(*8)

/*
 * Setup map
 */
$map = MapJson::create($mapJsonPath);

Now you can scan and get the result, _(*9)

$result = $scanner->scan($map);

Scanners

This library currently has only one scanner class using Imagemagick 6. It has been tested using the following configurations:, _(*10)

• PHP 7.3
• imagemagick6
• Extension imagick-3.4.4

See https://github.com/jansenfelipe/omr/blob/master/src/Scanners/ImagickScanner.php, _(*11)

Target Mapping File

It is a .json file that describes, in addition to the image information, the coordinates of the places (targets) that the script must do the pixel analysis. This file follows the following pattern:, _(*12)

{
    "width": 600,
    "height": 800,
    "targets": [
      {
        "x1": 50,
        "y1": 43,
        "x2": 65,
        "y2": 57,
        "id": "Foo",
        "type": "rectangle",
        "tolerance": 60
      }
    ] 
}

Example

In the example directory there is an image of a completed questionnaire response.png. There is also a map.json file that gives the coordinates of the image areas that will be analyzed the pixels., _(*13)

To help with setting up the environment, there is a Dockerfile in the project based on the official PHP 7.3 image that adds composer, imagemagick and the imagick extension to PHP., _(*14)

That way you can install the dependencies and run the command to process the image without headaches :), _(*15)

1) Clone this repo:, _(*16)

$ git clone https://github.com/jansenfelipe/omr.git
$ cd omr/

2) Install dependencies:, _(*17)

$ docker-compose run php composer install

2) Process example image:, _(*18)

$ docker-compose run php bin/omr scan example/response.png example/map.json

License

The MIT License (MIT), _(*19)