How to remove curly line on image

Question

I use tesseract ocr to recognize the text on the image. I have a problem with images that have curly lines. I tried various method such as threshold, gaussian filter, extract by color.. but I cannot remove it. I want to delete the lines without loosing the numbers

curly line on image

This is the image using the threshold method

image use theshold method

I’m using opencv for image processing and tesseract 4.0 for recoginize the text

Any hint or some sense of direction will be much appreciated. Thanks in advance for your help.

problems like this are best solved using tailored classifiers. Using higher image resolution and less compression would also help a lot. — Piglet, Apr 23 '18 at 10:25
@user2986898 yes, i tried but it lose stroke of number. thank for your suggestions — Đá Cuội, Apr 24 '18 at 07:50

score 5 · Accepted Answer · answered Apr 23 '18 at 11:56

5

I tried multiple approaches. The following one is the closest I could get to.

Simple Algorithm:

Obtain green channel of the image
Apply Gaussian blur of kernel size (3x3)
Apply histogram equalization
Find a suitable threshold to get the desired result

This is just a starter. You can get far better result if you incorporate adaptive threshold techniques and morphological operations.

(I have the code available in case you need it)

answered Apr 23 '18 at 11:56

Jeru Luke

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I am having a similar challenge. Can you please share the code if available? – Srijan Sharma Jan 11 '21 at 17:43
@SrijanSharma I'm sorry, this was written more than 2 years ago on my old laptop – Jeru Luke Jan 12 '21 at 09:51

How to remove curly line on image

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