remove dots from picture before OCR

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faboloso
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remove dots from picture before OCR

Post by faboloso » 2019-08-14T07:29:17-07:00

Good morning,

I am new to the forum but I have been using ImageMagick for a while in python script in combination with OCR

Last time I used to remove lines from text and then OCR it

But for this project I am not sure which parameters to use. I hate to ask and not really asking for someone to spoon feed me but anyone can guide me a bit on which parameters I should use to get clear text / no dots or even white background (OCR still recognize it this way already for maybe 60% right)

here is my picture example, any help will be much appreciated.

Image

Thank you

Werty
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Re: remove dots from picture before OCR

Post by Werty » 2019-08-14T07:47:09-07:00

Um, a question first, would we be helping you circumventing some kind of validation "Captcha" like system ?
Windows 7 user

faboloso
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Re: remove dots from picture before OCR

Post by faboloso » 2019-08-14T07:58:30-07:00

No this is not intended for captcha, and not bypassing any captcha system, just reading the information from picture

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fmw42
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Re: remove dots from picture before OCR

Post by fmw42 » 2019-08-14T09:45:56-07:00

You can use -connected-components to remove small dots.

Image

Code: Select all

convert img1.png \
\( +clone -threshold 70% -negate -type bilevel \
-define connected-components:area-threshold=5 \
-define connected-components:mean-color=true \
-connected-components 4 \) \
-alpha off -compose copy_opacity -composite \
-compose over -background white -flatten \
img1_result.png
Image

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