Diff GIF Maker (Beta)

Always respect artists' copyright, and don't share animations based on someone else's work without their permission!

Settings are currently lost when the page is reloaded!

This tool allows you to create high quality animation loops from two images according to a configurable effect.
The output is either a high-quality WebM video or a GIF with potentially reduced colours.

The conversion happens in the browser on your device, so the images aren't uploaded anywhere.
However, this means the page could crash if you try to create a large file with very high quality settings.

Features:

• Anti-aliasing for smooth motion even at low speeds and resolutions.
• Linear colour blending for beautiful fades and transparency.
• Multiple-effects:
  • cut-in window (horizontal or vertical)
  • cross-fade
• Live-preview.

If you have any suggestions for additional effects or features, please let me know in the comments below!

^{Also, if you like this tool, please consider leaving a rating or a tip. Thank you!}

Known issues:

• Generated GIFs don't pause properly when uploaded to Mastodon. This is a known Mastodon bug. Please upload the animation as WebM instead where possible.
• GIF does not support 60fps exactly, so the frame times may be longer than expected. You can reduce the  FPS to 50, 33 or 25 to get more accurate GIF timings.
• Some colours in the GIF may be wrong or change.
  • Currently, only the 256 most-used colours are preserved.
  • There is no dithering yet; remaining colours are snapped to the closest (by sRGB distance).
• The page freezes for a bit when saving the animation. This is expected, as I didn't move processing into a background thread.
• This tool doesn't easily work offline yet. I know that's important, so I plan to look into it eventually.
• WebM output is currently not supported in Safari (16.4), and there isn't a helpful error message yet.
  • Consider using a recent version of Firefox (96+) instead.