Fake 'hand signed and scanned' PDFs in MacOS


Despite doing all of my signing of PDF's with the preview sign tool sometimes I get asked to provide 'wet' signatures, using imagemagick to mess up the PDF a little and make it look like it's been scanned

Install ghostscript and imagemagick

brew install gs imagemagick

Then run for input.pdf (change the name to your file)

convert -density 150 input.pdf -rotate "$([ $((RANDOM % 2)) -eq 1 ] && echo -)0.$(($RANDOM % 4 + 5))" -attenuate 0.4 +noise Multiplicative -flatten -attenuate 0.03 +noise Multiplicative -sharpen 0x1.0 -colorspace Gray output.pdf

Also to note, I think signatures are a stupid way of proving identity and intent in total.

Further Reading

Scanner.sh Gist FalsiScan