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F/X>Stegano

Posted: 2015-12-05T09:33:13-07:00
by jeffm
I have the same question. I am using PHP Imagick::steganoImage to save a watermark. This appears to work fine. However what are the PHP Imagick methods that I need to use to extract the watermark?

Re: F/X>Stegano

Posted: 2015-12-05T15:03:15-07:00
by Bonzo
I am not sure how to recover it In Imagick but you probably need the watermark size and offset.

One thing to remember is that if the image is modified in any way it will probably not be possible to recover the watermark.

Re: F/X>Stegano

Posted: 2015-12-08T18:09:41-07:00
by jeffm
I looked through the imagick methods and I don't see anything that looks like it can recover the hidden watermark image. Is it possible that the API to recover the image was never made? Any info on where to look for this would be helpful. I have looked all over the web and see nothing that explains how to do this!

Re: F/X>Stegano

Posted: 2015-12-08T18:57:48-07:00
by fmw42
The only information I know is at
http://www.imagemagick.org/script/comma ... hp#stegano
http://www.imagemagick.org/Usage/transform/#stegano

I do not know if that is implemented in Imagick. Imagick has been very behind Imagemagick for years. I believe that someone is now working on bringing it up to speed, but I do not know of any details.

You should be able to bring it back using PHP exec() following the commands in the references above.