Optical mark recognition reads scanned OMR sheets. If you have plain paper OMR sheets that will be processed with OMR software, the OMR sheets can be scanned using your regular document scanner or you can keep a dedicated document scanner with the resolution set for getting clearly scanned OMR sheet images.
Scan the OMR sheets at a resolution of 300 dpi using a reasonable quality image scanner. An ADF scanner, with an automatic paper feed tray makes omr sheet scanning easier and accurate.
Identifying barcodes on OMR sheets must be accurately detected for the omr sheets to be recognized by optical mark recognition software and the filled in checkboxes will be accurately captured when the OMR sheet images are clear.
Scanned OMR Sheets
Plain Paper OMR sheets being scanned with a document scanner for OMR Software.
Scanned OMR sheet images must be clear and sharp so they can be recognized by the OMR software.
Page identifying barcodes must be free from imperfections so they can be read by Optical Mark Recognition Software.
The OMR bubbles on the scanned images must be clear so that the filled in bubbles can be accurately detected by the OMR software.
Barcode Detection: This is a clearly scanned barcode detected by OMR Software. Imperfections in scanned barcode images(such as white dots on the black) cause the omr sheet to be unrecognized by optical mark recognition. Badly scanned omr sheet images would have to be re-scanned to get better images and uploaded into the software again.
Requirements for OMR Software Scanning
Flatbed scanners and document scanners are image scanners that can be used for scanning OMR sheets for optical mark recognition form processing. A decent quality document scanner with an automatic paper feeding tray is recommended for fast easy scanning of OMR sheets, where as Flat bed scanners are used if not many OMR sheets are being scanned.A TWAIN compliant scanner is desirable for one click scanning.OMR software requires clearly scanned images of the OMR sheets to accurately detected the barcodes and the checkboxes. A resolution setting of between 200 and 300dpi is recommended for scanning OMR sheets but this will depend on the quality of the scanner that is being used. If the image produced isn’t clear or has imperfections a higher resolution setting should be tried. The OMR sheet images are saved as PNG, GIF OR TIFF files, but they are not photographs so don’t save as JPEG files.
Recommended Scanners for Optical Mark Recognition
Optical mark recognition captures the value of checkboxes which have been detected as filled and converts this information to readable checkbox value data(A,B,C,D) . Optical mark recognition is fast and accurate and captures and processes the checkbox responses into readable information from OMR sheet forms at a rate of around 30 pages per minute, saving much valuable time and producing faster analysis data from multiple choice response forms used for exams, tests, surveys, checklists, order forms and ballot forms.
Tips for OMR sheet Scanning
- Place the OMR sheets in the paper feeding tray, without overloading, and align the paper guides.
- If you don’t have a TWAIN compliant scanner, scan omr sheets at 300 dpi black and white and save as Tiff image files.
- Don’t fold omr sheets as a scanned fold line will show up as a black line on the scanned images which could interfere with detection of the checkboxes if it is too close. When an OMR sheet must be folded, it is better to design the OMR template with a dotted fold line that is well clear of barcodes and OMR bubbles.
- Clean the scan head regularly to avoid black marks appearing on the scanned images.
A clearly scanned OMR sheet image. Checkboxes that have been fully shaded with a dark pen or pencil are accurately detected and the value data is captured by optical mark recognition.
Clearly scanned omr checkboxes. The filled checkboxes are accurately detected and the checkbox values are captured. Unclearly scanned OMR sheets can cause all sorts of imperfections with the checkbox images such as broken borders and black where there should be white. Imperfections can cause distortion of the number of black pixels detected inside checkboxes which causes errors with the captured mark data.