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Detect Number/Letter using Aspose.OMR for .NET

I need a solution to read forms that contain:

  • checkboxes (ticks or crosses, not bubbles that have to be coloured in)
  • number fields (can be separated into boxes, i.e. DOB: [ ] [ ] / [ ] [ ] / [ ] [ ] [ ] [ ])
  • text fields (cab be separated into boxes, like date)

Looks like OMR cannot do this, is this correct? I looked at Aspose OCR and the examples are all machine generated text not handwritten numbers / block letters.

Happy to work with OMR templates to give bounding boxes, etc to help the engine but I do need the flexibility for numbers / letters / checkboxes…

@gatapia

Could you kindly share an image on which you need to detect the mentioned symbols. We will further proceed to assist you accordingly.

Sure, I’d like to recognise a form like this:
scan_1.jpg (118 KB)

@gatapia

We have logged an investigation ticket as OMRNET-44 in our issue tracking system. We will further investigate the feasibility of required support and keep you informed with the status of ticket resolution. Please be patient and spare us little time.

@gatapia

It is possible to recognize ticks and crosses using Aspose.OMR, and the quality will be further improved with upcoming versions. Unfortunately, for the moment we do not provide numbers or text recognition functionality.

We suggest trying out Aspose.OCR, it has the functionality to specify area of interests and with some tuning you should be able to recognize letters and numbers. Take a look at GitHub samples for examples of specified recognition blocks: https://github.com/aspose-ocr/Aspose.OCR-for-.NET/blob/master/Examples/CSharp/FormattingAndManipulatingOCR/AddingUserDefinedRecognitionBlocks.cs

Please, how can I recognize ticks and crosses using Aspose.OMR? I didn´t found any option to perform this operation.

@isabela.gehren

You can perform OMR on Images having ticks and crosses with the respective OMR template. Please use the code snippet in the linked example. In case you face any issue, please share your source files i.e. image and template with us. We will test the scenario in our environment and address it accordingly.

Aspose.OMR.zip (244.6 KB)

Using the mentioned code, the ticks and crosses were not recognized in answers 37, 38 and 42. It´s very important for me the tick in answer 42 be recognized because in my case those both marks should invalidate the answer.

Please let me know if there is some parameter that performs this recognation.

@isabela.gehren

In order to recognize the ticks and crosses correctly, the bubbles should be filled enough. So it depends much on how large ticks and crosses actually are. At the moment, they can be recognized by adjusting the threshold value. For example, they can be detected in your image by adjusting threshold to 23.

Yes, more precise detection would handle such marks even if they are quite small and do not take large areas but, this is still in prototype stage and we are working over it. In future versions of the API, recognition quality would be improved.