Gimp Tips

This tutorial will take you through the process of removing image backgrounds step-by-step using the freely available gimp software. This tutorial assumes you are running the Windows version, but the concept applies equally to other versions of the gimp and other photo editing software such as Photoshop.

The assumption is that you have a basic understanding of how to use the gimp.

There are many ways to achieve this - the method that we will describe here uses the Fuzzy Select Tool - a fairly quick and precise method that can be mastered easily (the image below took around 15 minutes to remove the background from).

Step 1 - Select the Image Background

Using the Fuzzy Select Tool select the part of the image that you wish to remove. The aim is to end up with an image which resembles the one below.  You should have the "marching ants" around the area of the image that you wish to keep.

Fuzzy Select Tool

Background Selected

1. Select a large even couloured area in the background to start with.
2. Add to the background by clicking on other parts of the background.  Be sure to change the Fuzzy Select Mode to "Add to the Current Selection"  this can be done from the tool options or by holding down the Shift key.
3. Once you have selected the bulk of the image background you may you will need to zoom in to finish it off properly.  I find that zooming to 400% works well.
4. You will most likely need to adjust the threshold as you go to make the selection more or less sensitive.
5. You may find that you have selected some areas that shouldn't be.  This is easily fixed by changing the Fuzzy Select Mode to "Subtract from the Current Selection".  This can be done from the tool options or by holding down the Ctrl key.

Image Zoomed to 400%

 This is what you are trying to achieve around the entire outline of the portion of the image that you wish to keep.

Step 2 - Add Transparency to the Image

Add transparency to the image by using Layer > Transparency >Add Alpha Channel.  This makes it easy to add another background layer or paste your selection into another image.

Add Alpha Channel

Step 3 - Delete the Background

Press the Delete key to remove the selected background.  You should be left with your selection on a checked or transparent background.

Background Deleted

 If you were to save the image at this point you would have an image without the background but with jagged edges.

Background Removed and Jagged Edges

Step 4 - Smooth the Edges

Grow the Selection

Grow the slection by 2-3 pixels

Apply a Gaussian Blur to your Selection

This is done from Filters > Blur > Guassian Blur

Antialiased Edges After Applying Guassian Blur

Step 5 - Save the Image

If you are saving th eimage as a JPG (which you probably would be for display on a website) you will need to select Export when prompted as JPG files don't support transparency.  The transparent part of the image will be filled with white.

Final Image - Background Removed and Smooth Edges