Adding a coffee stain to an image is a really cleaver effect to make it appear to have a stain left behind by a coffee cup. This effect would most likely take a serious amount of time, if done manually and is probably left only to those extremely talented in graphic design. Thankfully, for the rest of us, GIMP offers us the ability to pull off this effect through the use of a Filter.
Working with Coffee Stains
Coffee stains are provided through a filter. Unfortunately this filter does not allow the user to choose where the stains will be placed when created. However, each stain will be created and placed on its own layer. This makes it easy for each stain to be relocated to the desired location.
Adding Coffee Stains
For this article, choose any image you might have on your computer. The exact image used is not important to learn this technique.
From the Filters menu, choose Decor >Coffee Stain… Set the number of stains to the desired amount, ranging from one to ten. De-select “Darken only” if desired and click OK.
Resizing Coffee Stains
The coffee stain filter auto generates the stains, including their size. If you are not happy with the size of a particular stain, resize it. Since each stain is on its own layer, we can resize the layer. From the Layer menu, choose Scale Layer. Adjust the height and width. Click Scale.
Moving Coffee Stains
Since each stain is placed as a layer, we can move the stain to the desired placement on the picture. From the toolbox, select the layer from the listing in the Layer selection tab. Tools Option tab, make sure “Move the active layer” is selected. Move the stain to where you want it. Be sure to repeat with each stain.
Note: If the tab is not there, follow the directions in “Working with the Toolbox in GIMP”.
Having Fun With the Stains
The stains created in GIMP come out brown, which makes sense as coffee stains. Yet coffee is not the only possible stain left on an image. Have some fun by changing the color of the stain.
With the stain layer selected, colorize the stain by selecting colorize… from the Colors menu. Slide the hue to the left or right to change the color. The saturation selector allows you to choose how much of the color will be shown, while the lightness selector allows to lighten or darken the stain itself. When done, click OK.
Saving the Image
Saving the image provides you with the same options here as with any image created or edited in GIMP. If you wish to save the image will all the layers intact and editable, save the file as an XCF. Otherwise save the image in your preferred format.