Texturing

Texturing Images with The GIMP

Original	Matte Texture

Thank’s to Xach’s tutorial Bump Maps are Cool, I was inspired to add matte finishing as a GIMP For Photographers tutorial. Here then, is a short tutorial on giving your photos a matte (or any other) texture.

The Procedure

Load your image that you want to add texture to into The GIMP.I recommend that you resize it for the final target resolution prior to adding texture. Then zoom in to 100% view.
Load a texture that will be used for bump mapping. Unless it is a random texture, you’ll probably want to use a tileable one. See the Further Reading section for some sites with tilable textures, and a tutorial on making general textures tileable.You can also create one on the fly. A simple way to create a decent matte texture is as follows: Create a new 256×256 grayscale image (File/New), filled with White. Run Filters/Noise/Noisify and a gray value in the 50-100% range. Here I used 90% (0.90). If the noise is too soft, you can use Levels (Image/Colors/Levels) to darken the noise a bit. With 90% I did not need to darken it. Finally, run a Gaussian Blur (Filters/Blur/IIR Gaussian Blur) on the noise. A 1 or 2 pixel radius should do it. If you want a copy of this noise texture, here it is.
Open the Layers dialog and make sure that the original image is listed in the drop-down box. Right-click on the Background layer and select Duplicate (there is also a button for this in the bottom button bar of the Layers dialog ().Now double-click on the duplicate layer and rename the new layer “Matte Finish”. This step is not strictly necessary, but it is helpful to prevent confusion about what is on each layer, especially if you add some additional layers for other editing purposes, or more importantly, if you save the file with layers and open it six months later.
Back in the image window, run the Bump Map filter (Filters/Map/Bump Map).In the Bump Map filter options, check “Linear Map”, “Compensate for Darkening”, and “Tile Bumpmap”. Choose the blurred noise image in the Bump Map drop down box. Play with the Parameter Settings sliders while viewing the preview window till you see the effect that you are looking for. Try to center the preview window on an area of the image that is more or less continuous in tone and doesn’t have a lot of detail (e.g. not a face). At this point you want the effect to look a little too strong (this will be remedied in the next step). Click OK to apply the filter. If you are unhappy with the result, Undo (Ctrl+Z) and invoke the filter again (Alt+Shift+F) with different settings till you are satisfied.
To fine tune the strength of the effect, adjust the Opacity slider of the Matte Finish layer in the Layers Dialog. Here I tried two different settings: the first is with an opacity of around 20% and a Normal layer blending mode; the second is at around 50% opacity with an Overlay blending mode. I prefer the Overlay version myself.Click the “eye” next to the Matte Finish layer in the Layers dialog on and off to quickly view the effects with and without the texture.

Tips

• The main issue with creating a matte finish or any other texture digitally is targeting the output image size, magnification and resolution, all of which affect the quality of the perceived texture. Whether your output target is a monitor at 72 dpi or an inkjet at 300 dpi, you will need to experiment to find the texture pattern, intensity and level of opacity that gives the desired result for your particular output.
• GIMP patterns make great textures. Check out the Patterns dialog to see some of the possibilities. To use a pattern as a bump map, just create a new image (or better yet, a layer), choose Bucket Fill with the “Pattern Fill” option set in the Tool Options dialog, select a pattern from the Patterns dialog and click to fill.
• Texturing is great for large, smooth areas of light color. It works especially well for mats and frames.
  

  Untextured	Textured

Further Reading

• Xach’s tutorials on the subject are most useful: Giving your images a canvas texture and Bump Maps are Cool
• Making tileable textures with gradient brushes.
• Some GIMP-generated Textures
• Some nice textures/patterns from Studio Tecnico