MATLAB Answers


Text extraction from a binary image

Asked by Soumyadip
on 29 Mar 2013

I am doing a project to read the data on a calculator screen via image processing. I need to make the image binary in such a way that only the digits in the image appear black and the rest is white. Can I do it with any image enhancement tool? Please suggest. Can somebody do it for me?

The link to the image is -

Thanks in advance

  1 Comment

There is no image in that link,it is saying doesn't exist.

1 Answer

Answer by Chandra Shekhar on 29 Mar 2013
 Accepted answer

use 'histeq' function for enhancement or use 'adapthisteq' by choosing proper clipping range.

After applying this method convert to binary.


I tried applying histeq but neighboring regions other than the digits are also turning out to the black which is undesirable. What to do?

I applied adapthisteq and converted to binary but I am getting dark patches like -

Please advise how to remove the dark regions

See my answer to your duplicate question. I got the numbers out of there using color segmentation and some standard image processing to clean up some noise. I didn't even have to do background correction. You should not accept an answer if it didn't answer your question.

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