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Changing default CAPTCHA color

Asked by Allen Macbean
Posted January 28, 2014.

I’m using the MT CAPTCHA to verify real comments on our blog, but the CAPTCHA is unreadable. I have a black background on the blog, the the CAPTCHA is black type on a dark grey/black pattern. How does one change the colors of the CAPTCHA?


1 Answer

Charlie Gorichanaz

Charlie Gorichanaz on February 14, 2014, 3:04 a.m. Reply

Hello Allen,

In a default Movable Type installation, the source images used to build the CAPTCHAs are stored in mt-static/images/captcha-source.

These images could be edited to change their colors, but it would be safer to make a copy of the directory (such as /mt-static/images/captcha-source-green), edit those images and then point MT at the new directory by adding a CaptchaSourceImageBase directive to the mt-config.cgi configuration file.

Note the new images should keep the same dimensions and properties, such as the characters having transparent backgrounds.

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Charlie Gorichanaz

Charlie joined Six Apart as a Japan based product manager for Movable Type in February 2014 after spending two years as a developer for 601am. Previously he was the web director of The Badger Herald while studying biochemistry at the University of Wisconsin-Madison.

Twitter: @CNG

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