This project creates animated GIFs of horses in motion using photographs by Eadweard Muybridge. The output GIF files consist of bilevel images so that they can be shown in quick succession on an e-paper display using the animation (A2) waveform mode, which works only with pure black and white pixels.
The source files are taken from the following pages on Wikimedia Commons.
- The_Horse_in_Motion-anim.gif – Muybridge's The Horse in Motion, 1878. Animation by Nevit Dilmen.
- Muybridge_horse_pacing_animated.gif – Animated sequence of a horse pacing, by Waugsberg.
- Muybridge_race_horse_animated.gif – Animated sequence of a race horse galloping, by Waugsberg.
- Horse_gif.gif – Animation made by rotoscoping a horse's gallop, by Lennart Rikk.
All of the source animations from Wikimedia Commons are in the public domain. The other content of this project is licensed under the GNU General Public License v3.0.
The animated GIF files produced by this project are licensed under the Creative Commons Attribution Share Alike 4.0 International license.
The Makefile requires the following programs on your PATH environment variable.
- convert – converts between image formats and edits images (from ImageMagick)
- mkbitmap – transforms images into bitmaps with scaling and filtering (from potrace)
- potrace – transforms bitmaps into vector graphics (from potrace)
- inkscape – an SVG editing program (from Inkscape)
This project creates the following animated GIF files. To see how the hand-edited frames were created, open the SVG source file in Inkscape, which will display the off-page images along with the image framed by the page.
- horse-motion.gif – traced with potrace
- horse-motion-cutoff.gif – created in Inkscape using the brightness cutoff mode of the Trace Bitmap tool
- horse-motion-edge.gif – created in Inkscape using the edge detection mode of the Trace Bitmap tool
- horse-pacing.gif – traced with potrace
- horse-racing.gif – traced with potrace
- horse-traced.gif – traced with potrace from a threshold cutoff bitmap
- horse-traced-cutoff.gif – a threshold cutoff bitmap
A single frame from each of the original animations is converted as illustrated below. The Vector column shows the rasterization of the vector graphics created by potrace.
| Original | Vector | Brightness Cutoff | Edge Detection |
|---|---|---|---|
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| Motion 340 × 230 px | 800 × 541 px | 800 × 541 px | 800 × 541 px |
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| Pacing 245 × 188 px | 800 × 614 px | ||
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| Racing 300 × 200 px | 800 × 533 px | ||
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| Traced 320 × 200 px | 800 × 500 px | 320 × 200 px |