i have no way now of verifying that it is in there.
You can only retrieve the hidden image if you know that it's there, and know its size and offset (that's the point of steganography). There's no way to "check" in general whether something is hidden if you don't know precisely how to retreive it.
-stegano
hide watermark within an image. Use an offset to start the image hiding some number of pixels from the beginning of the image. Note this offset and the image size. You will need this information to recover the steganographic image (e.g. display -size 320x256+35 stegano:image.png).

http://docent.hogent.be/~pvt340/multimed/webpages/combine.html

This probably translates into PerlMagick like this: 

my $img = Image::Magick->new;
$img->Set(size=>'100x100+5');
$img->ReadImage('stegano:result.gif');

[download]
If this produces an image that "makes sense", then you know the watermark was there. Otherwise, you'll probably get random pixels.

blokhead

In reply to Re: Image::Magick stegano question by blokhead
in thread Image::Magick stegano question by bear0053

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