how to add watermark with Magick++?

[shangjiuliu]

how to add watermark with Magick++?

[dlemstra]

There are various ways of doing this. You can find the command line examples here: http://www.imagemagick.org/Usage/annotating/#watermarking

And here is a translation of one of the examples:
composite -dissolve 25% -gravity south wmark_image.png logo.jpg wmark_dissolve.jpg

Image watermark("wmark_image.png");

Image logo("logo.jpg");
logo.artifact("compose:args", "25%");
logo.composite(watermark, GravityType::South, CompositeOperator::DissolveCompositeOp);
logo.write("wmark_dissolve.png");

[dlemstra]

Did this answer your question and can we close the issue?

[shangjiuliu]

Yes.
another question:
Image watermark("wmark_image.png");
how do i get the data of watermark?

i can do like this:
Blob ret;
watermark.write(&ret);
ret.data();
is there another way get the data of watermark?