Create a bitonal image for OCR using Image Magick

Posted by Greg on Stack Overflow See other posts from Stack Overflow or by Greg
Published on 2010-05-13T23:47:29Z Indexed on 2010/05/13 23:54 UTC
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image

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imagemagick

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ocr

nice /usr/local/bin/convert -colors 2 -colorspace gray -compress group4 /var/www/html/uploads/pokemon.jpg /var/www/html/uploads/pokemontest.jpg

This command worked with a really OLD version of Image Magick.

With the newest version this method produces a completely black image.

nice /usr/local/bin/convert -colorspace gray -compress group4 /var/www/html/uploads/pokemon.jpg /var/www/html/uploads/pokemontest.jpg

nice /usr/local/bin/convert -colors 2 /var/www/html/uploads/pokemontest.jpg /var/www/html/uploads/pokemontestfinal.jpg

This results in a bitonal gray and black image, but it's really rough. NOT clean at all.

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