How to make a transparent background/selection on an image using GIMP

March 20, 2006 · 1 min read
  1. Open your image.
  2. Select the area you want to make transparent.
    1. Select the appropriate selection tool from the Tool window or the Tools - Selection Tools menu on the Layer window.  I usually use the magic wand/fuzzy select (Select contiguous region) tool or the Select regions by color tool.
    2. Click in the region you want selected.  Use shift-click to add more regions/colors.
      Tip: It's easier if you zoom in (View - Zoom menu) to see finer details of exactly what you're selecting.
  3. In the Layer window (the one showing your image), select Layer - Transparency - Add Alpha Channel.  If this is blanked out then it's already done.  This makes sure your image can store transparency data.
  4. Select Edit - Clear.  This makes the selection transparent.
  5. Save the file. 
    Note: If you save it as a PNG file, be sure to select the 'Save colour values from transparent pixels' option in the Save as PNG dialog box.

And that's it.

NOTE: IE does not support showing PNG transparencies (alpha channels) natively.  There are a few work arounds for this (theres loads to be found on google) - here's MS's solution.  However, personally, I find the simplest approach is to save the image as a GIF (which all major browers support transparencies for).

When saving your image as a GIF from within Gimp, it will prompt you to export it - you can select either Indexed or Greyscale - however, on the next screen (Save as GIF) be sure to check the 'Interlace' option.

HTH

Tim

This article is part of the GWB Archives. Original Author: Tim Huffam

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