[Solved] Remove cutout residue (transparent background picture)

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Rye
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[Solved] Remove cutout residue (transparent background picture)

Post by Rye » 2018-11-06T13:32:27-07:00

So, as so often, when someone uses any app to remove the background (mostly with the magic wand tool), you might end up with this:

Image

As it is plain to see:
Around the contours, there is a white "residue", that couldn't be removed with the programs tool.

Question:

Can imagemagick help here ?
(I heard about a -trim option, but that only seems to be appropriate if the background is entirely colored ?)

- Thanks in advance.
Last edited by Rye on 2018-11-07T09:58:04-07:00, edited 1 time in total.
Version: ImageMagick-7.0.7-28-Q16-x64-static http://www.imagemagick.org
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fmw42
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Re: Remove cutout residue (transparent background picture)

Post by fmw42 » 2018-11-06T17:39:38-07:00

try a little anti-aliasing of the alpha channel as follows:

Code: Select all

convert image.png -channel a -blur 0x1 -level 50x100% +channel result.png
Adjust the blur x1 value as desired.

Rye
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Re: Remove cutout residue (transparent background picture)

Post by Rye » 2018-11-07T09:03:32-07:00

Works perfectly !

The blur variable changes the way the edges are smoothed ?
Version: ImageMagick-7.0.7-28-Q16-x64-static http://www.imagemagick.org
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fmw42
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Re: Remove cutout residue (transparent background picture)

Post by fmw42 » 2018-11-07T10:04:21-07:00

Rye wrote:
2018-11-07T09:03:32-07:00
The blur variable changes the way the edges are smoothed ?
Yes, larger blur value than 1 (0x1) will smooth more and you will lose more edge data. You probably can reduce the 1 to 0.5 as about the minimum that you can detect. But it may be too small to make a change. Try different values and see what looks best to you.

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