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In many instances, images can speak for themselves. However, one often wants to put arrows or indicators on an image mentioned in the caption or the text. This article explains a few ways to do that with the GIMP.

I was talking with a friend the other day about making figures for publication. She said that the one thing that frustrated her about using the GIMP to create figures was that there was no easy way to put arrows on the figure. Someone else in the room suggested that Inkscape was the right tool for the job.

So I've been thinking about it, and while Inkscape is a great tool for vector graphics, I don't think it is what we want in this case. The specific case is that you are starting off with a raster image and want to end with a raster image, but just want to put a few arrows on it. Taking that into a vector graphics program really isn't the best solution.

So I hunted around a little bit, and came up with two solutions using the GIMP.

The first involves downloading and installing the GFXArrows plug-in for the GIMP, a part of the Graphics Muse Tools package. Michael J. Hammel, the tool set's author doesn't seem to have a page describing the current version (3.0.0B2 at the time of this writing) of the plug-in up, but I found one from a previous version that has some good description and screenshots of what you'll get (be careful not to download the 0.4 version from this old page).

The upside is that this has a pretty decent little interface and once you get the hang of it, arrow creation is quite simple. The downside is that unless you are running on a unix machine where you can compile the code, you may be out of luck.

The second way is less elegant but requires nothing more than the GIMP, a font that has arrows (I have one called Wingdings), and some work with the rotation tool. In many ways, that sentence really said it all, but let me elaborate. One of the fonts that your version of the GIMP probably has contains a font of little icons or dingbats. You may have to type out all of the letters on your keyboard to find out which ones they are, but in one of those fonts will be some arrows usually pointing in the cardinal directions. Make a text layer with just one letter from this font, say the up arrow. With the GIMP you can choose any color for your font, and you can scale it to be whatever size you like. If you need a longer tail, you may need to go in and use the selection tool to make a copy of the tail that is there and then repeatedly paste it on the end. This will convert that layer from a text layer to a graphics layer, but that's fine. You may also need to make the layer bigger to accommodate your longer tail. Once you do this, you just have to work with the rotation tool to get your arrow pointing in the right direction.

The upside is that there is no extra software to install. The downside is that it is a lot of manual labor to just get an arrow on your image.

If you have another way of getting arrows onto your images, please share them below.