Legacy ImageMagick Discussions Archive

Hello all,

I want to write a drop shadow script, now I've drop the shadow successful.

Use the following command(it isn't written by me, I checkout from gscrot).

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convert "${FILE}" \( +clone -background gray -shadow 80x3+5+5 \) \
+swap -background none -mosaic +repage "${FILE}"

The question is, I want to do a alpha border in the northest, this command will apply the alpha border in all sides, but I only want to apply at northeast.

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convert -bordercolor 'rgba(255,255,255,0)' -border 10x10 test.png test_out.png

So how can I do it?

Oh, I got it:

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convert test.png -gravity northwest -background 'rgba(255,255,255,0)' -splice 20x20  test_out.png

The PROPER solution is to NOT use -mosaic which only extends the virtual canvas right and downward, but clips images in the other direction.

Use instead -layers merge and follow with +repage to remove the image offset.

See IM examples, Shadow...
http://www.imagemagick.org/Usage/convolve/#shadow

which uses this technique, and goes to explain what is going one, as well as alternative solutions, such as what you discovered.

Legacy ImageMagick Discussions Archive

How to do only northeast border?

How to do only northeast border?

Re: How to do only northeast border?

Re: How to do only northeast border?