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help with OCR

I am doing a project where I need to do OCR on some printed lables

 

the font size is on 4...

and I am having a hard time seperating the letters - I am getting closer, but any hints would be highly appriciated!

 

ocr1 - orginal image

ocr3 - incresed brightness and contrasts

ocr4 - converted to binary, and used erode

 

 

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Message 1 of 7
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Try Gray Morphology - Dilate followed by Threshold.  To separate characters you need to be able to draw a straight line vertically between characters without touching anything (blank space).  You need to have at least one-pixel between characters.  See attached image and example.

 

 dialateThreshold.PNG

 

Matthew Fitzsimons

Certified LabVIEW Architect
LabVIEW 6.1 ... 2013, LVOOP, GOOP, TestStand, DAQ, and Vison
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Thanks a lot, will try this tomorrow
Why dialate and not erode?
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Yes, seems to work in reverse of what you would think.  Play with both and you will see why I chose dilate.

 

Matt

 

Matthew Fitzsimons

Certified LabVIEW Architect
LabVIEW 6.1 ... 2013, LVOOP, GOOP, TestStand, DAQ, and Vison
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I will 🙂
And I was not aware that a straight horizontal line was needed to separate the letters, that explains a lot!
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Meant Vertical line of course ...
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That is why you get to enter a security phrase when you buy tickets to prevent OCR automated buying.

 

securityPhrase.PNG

 

Matthew Fitzsimons

Certified LabVIEW Architect
LabVIEW 6.1 ... 2013, LVOOP, GOOP, TestStand, DAQ, and Vison
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