Software I like: GIMP

Graphics by GIMP

Release notes

My notes

Single-window and multi-window modes

An optional single-window mode was introduced in GIMP 2.8 (ref), with multiple images in tabs instead of in separate windows. It seems that this became the default mode in GIMP 2.10, although it's not mentioned in the release notes. The mode can be changed by checking or unchecking Single-Window Mode in the Windows menu.

Scripts

To install and use a Script-Fu script: download the script and store it somewhere (e.g., ~/Downloads/GIMP/). Determine where your scripts directory (e.g., ~/.gimp-2.8/scripts/) is by doing Edit ► Preferences ► Folders ► Scripts. Copy the script to that directory. Do Filters ► Script-Fu ► Refresh Scripts.

The new function should now appear in some menu. If you have trouble finding it, do Help ► Plug-In Browser and hunt for it, or look for it under the ‘root file menu filters’ (ref; I don't actually know what that means). You can also look for the script-fu-menu-register command in the script itself to see where in the menu system it will go.

Stitching

For methods of stitching images together to make panoramas, see, for example, Stitch Panorama, Thomas R. Metcalf’s GIMP plug-in written in Python.

Animation

When exporting layers to an animated GIF, there doesn't seem to be a way to export only certain layers (e.g., the visible ones). My work-around is to delete the layers that are not wanted in the animation, do the export, and then use Ctrl-Z to undelete the layers. A Save beforehand can reduce stress.

The delay for an animation frame is set by editing the descriptive text of the corresponding layer, specifying the delay within parentheses (e.g., Frame 50 (100ms) for 100 milliseconds).

GAP

Download the Gimp Animation Package (GAP) from http://photocomix-resources.deviantart.com/. (GAP is currently intended for GIMP 2.6 but seems to work for for GIMP 2.8.) My Info-Zip was unable to unzip the file but I could unzip it using the unzip command in a VirtualBox Linux guest. In the resulting GAP.2.6_win\/ see HOW TO INSTALL.txt and TUTORIAL_Doc/Gap_Help_Tutorial/Gap-For-Animated-Gif-9937.html. Run GAP.2.6_win\GAP-installer\Gimp-GAP-2.6.0-Setup2.exe. Browse to select user\.gimp-2.8\plug-ins\ as install location. (When I did this, the GAP files gap_*.exe ended up in plug-ins\lib\ rather than in plug-ins\ itself. I manually moved them.)

At least parts of the tutorial included with the GAP installer are dated. See also the tutorials (also old) by Jakub Steiner: Simple Animations (without GAP), Using GAP and Advanced Animations Tutorial.

After opening an existing GIF animation, the first step in using GAP is to do Video ► Split Image to Frames. This stores each frame in a separate numbered image file and then displays the first frame image. A different frame can be displayed by doing Video ► Go To.

There is a crop-all-frames function but there doesn't seem to be a way to visualize the crop boundaries in the context of an actual frame. An alternative is to simply crop the original animated GIF before starting to use GAP.

There is a Video ► Playback menu entry; actual playback seems to be done by pressing on the up (or down) arrow of the current-frame-number box. Video ► VCR Navigator also provides playback.

AnimStack

This is another set of animation tools, in the form of a script: animstack.tumblr.com. I haven't tried it yet.

Tutorial for making a tilable grass texture

This is based on Pixel Byter's grass tutorial. I have removed the graphics and narrative, and made the menu choices more explicit. The specific parameter values are those suggested in the original tutorial, but of course can be varied to taste. For my own use I have omitted steps 2 and 3, to get the effect of a smooth lawn.

  1. File ▶ New, 400 × 1600 pixels
  2. Filters ▶ Render ▶ Clouds ▶ Solid Noise, Detail = 15, X Size = Y Size = 7, Tilable checked.
  3. Filters ▶ Blur ▶Gaussian Blur, Blur Radius 50×50
  4. Filters ▶ Noise ▶ RGB Noise, Correlated Noise checked, Red = Green = Blue = 0.5
  5. Filters ▶ Blur ▶Gaussian Blur, Blur Radius 0×5 (this step is to remove possible subsequent artefacts)
  6. Image ▶ Transform ▶ Rotate 90° clockwise
  7. Filters ▶ Distorts ▶ Wind, Style = Wind, Direction = Left, Edge Affected = Trailing, Threshold = 0, Strength = 10
  8. Image ▶ Transform ▶ Rotate 90° counter-clockwise
  9. Filters ▶ Map ▶ Make Seamless
  10. Image ▶ Scale Image to 400×200
  11. Colors ▶ Colorize, Hue = 90

R. Funnell
Last modified: 2021-09-18 09:19:50