Reading OMR Results

Aspose.OCR Product Family
1

Dear Sirs,


Attached is a sample bubble form that I have created a template for and am now testing the accuracy for the items that have been selected. I am having a couple of issues:

1. I believe that the form was filled in using a device with blue ink. Should only black be used?
2. In the OMR Template editor I have been using the mark threshold settings. Because the boxes have been checked I have reduced the threshold settings. The problem I am having is that I am getting false positives because the value is low and the bubble outline is appearing in the element. Is this occurring because of the color blue was used to mark the bubble form? Can the boxes be checked as was done in the attached sample have an expectation of 100% accuracy?

Scott


am trying to create


2
Hi Scott,

Thank you for your inquiry and providing sample sheet.

This is to update you that marking with Blue or Black are equal. The OMR engine looks for white pixels and non white pixels of the given area.

Furthermore with threshold value as low as 0.1 (10%) all marks are recognized as filled. Marks are considered to be filled because even the empty mark circle takes about 26% to 30% of the area depending on area size, whereas actually filled mark takes about 60% to 70% of the area. Therefore, if threshold value is set less than 30%, all marks are recognized as filled. Sample images are attached showing the percentage for better understanding.

Hope the above information helps. Feel free to reach us in case you have any query or comments.