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vielhuber/script.txt

Last active April 17, 2024 12:20
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ImageMagick: Increase pdf scan contrast and sharpening #tools
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script.txt
convert -density 150 input.pdf -brightness-contrast 5x25 -sharpen 0x1 output.pdf
convert -density 300 input.pdf -colorspace gray -normalize -level 50%,51% -sharpen 0x1 output.pdf
convert -density 300 input.pdf -colorspace gray -normalize -level 25%,26% -sharpen 0x1 output.pdf
convert -density 300 input.pdf -colorspace gray -normalize -modulate 150 -sharpen 0x1 output.pdf
convert -density 300 input.pdf -contrast -contrast -contrast -contrast -sharpen 0x1 output.pdf
convert -density 300 input.pdf -contrast-stretch 15% -sharpen 0x.5 output.pdf
find . -name '*.pdf' -type f -exec convert -density 150 {} -brightness-contrast 5x25 -sharpen 0x.5 {}_new.pdf \;
@munim
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munim commented Jul 25, 2023 •
edited

I had a bulk of unprocessed scanned of documents. I used the following which worked really great for me with a 72.3% file size reduction:

convert -density 300 input.pdf -normalize -sharpen 0x2 -compress jpeg -quality 70 output.pdf

@vielhuber
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Author

I had a bulk of unprocessed scanned of documents. I used the following which worked really great for me with a 72.3% file size reduction:

convert -density 300 input.pdf -normalize -sharpen 0x2 -compress jpeg -quality 70 output.pdf

Thanks, will try that also out.

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