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old_snippets/imagemagik-png-to-jpg-white-bg.en.md

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+---
+title: "imagemagik .png to .jpg with white background"
+seo_description: "snippet explaining how to use imagemagik to covert images from .png .jpg and make the transparent parts white"
+date: 2022-03-03T21:31:00+01:00
+draft: false
+snippet_types:
+- imagemagik
+---
+
+Working on some .png map files today. I needed to covert them to small .jpg's for
+uses in [Oblastle](https://oblastle.fun). Problem being by default the transparent part
+fills into to black. Here is how to make it white:
+
+
+```shell
+$ ls
+us-ak.png
+us-al.png
+us-ar.png
+us-az.png
+us-ca.png
+
+$ for file in *.png ; do magick mogrify -format jpg -resize '500' -background white -flatten  $file; done
+
+$ ls
+us-ak.png
+us-ak.jpg
+us-al.png
+us-al.jpg
+us-ar.png
+us-ar.jpg
+us-az.png
+us-az.jpg
+us-ca.png
+
+$ rm ./*.png
+```
+
+The important bit being **-background white -flatten**.
+
+[source](https://stackoverflow.com/questions/7943711/change-the-background-of-an-image-in-image-magick)