Bubble Vision: Optical Mark Reader

Extract answer choices from scanned jpg bubble forms.

Graphical User Interface

$ omrcmd.py

Command Line

$ omrcmd.py [options] imagedir

imagedir

Input image directory (front side). Lowest numbered image identifies the key.

--backdir=BACKDIR

Optional back side image directory

--form=FORM

Set the form string (default and only supported="882E")

--help

Show this help message and exit

Output

validation images

Answer bubble means and reference box fits drawn over each input image.

results.xlsx

summary

Image path, name box image, and total score for each test.

questioninfo

Answer choice counts by question. Key excluded.

scoring

Answer choice matches key (0/1). Same indices as choices. Score is 0 if key is -1.

choices

Answer choice matrix. Tests in rows and questions in columns. 0-4=A-E, -1=n/a.

Install

$ pip install omr
$ pip install --upgrade omr
$ pip uninstall omr

• Requirements
  • python 2.7+
  • pip $ easy_install pip
• Dependencies (installed by pip)
  • numpy 1.8.0 multidimensional numerical array object.
  • openpyxl 1.6.2 read and write excel xlsx files.
  • pillow 2.2.1 image manipulation.
  • yaml 3.10 human friendly data serialization.

Example Validation Image

Troubleshooting

• Windows
  • $ omrcmd.py --help gives omrcmd.py: error: too few arguments
    • fix argument passing to "py" file associations from python %1 to python %1 %*
  • unable to find vcvarsall.bat
    • I was able to use $ easy_install Pillow when pip failed to install Pillow 2.2.1

Author

Greg Miller [email protected]