Unfortunatelly a watermark doesn't work in the 7.x-1.0 release.
Here is a watermark patch for Imagemagick module.
After patch see the module setting.
You can add a string file URI or path of the watermark image. For example: sites/default/files/images/watermark.png (use transparent colors for the best result). Leave blank to disable.
Then, use new option (Add watermark) in "Configuration/Image style".
Closed: outdated
1.0
Code
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