How to protect text from recognition

Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
Post Reply
BertyWooster
Posts: 3
Joined: 2011-08-31T13:16:09-07:00
Authentication code: 8675308

How to protect text from recognition

Post by BertyWooster »

Hi!

I have couple of PDF files with text. I can "render" them to PNG with any dpi I like (with Ghostscript).
After "rendering" files, I get couple of black-white (even not grayscale) PNG files with rendered text.

So, there's the question - what is the best way to "distort" these files to protect them?

1) I understand that there's no absolute protection.
2) I need these files to be readable by men :) So, I cannot swirl or wave them, to make them captcha-like :)
3) I tried to replace plain color text (black) with gradient; tried to put watermark text of arbitraty angle; tried to play with colors. No way. At least, Abbyy FineReader easily read my texts.

I cannot realize, what to do.

Any ideas would be very appreciated.
User avatar
fmw42
Posts: 25562
Joined: 2007-07-02T17:14:51-07:00
Authentication code: 1152
Location: Sunnyvale, California, USA

Re: How to protect text from recognition

Post by fmw42 »

Take a look at my captcha script -- I randomly rotate/skew the letters and draw random lines through them. see the link below.
Post Reply