Making smaller animated GIFs with Paint by Zaweba
Shrink animated GIFs in Paint by Zaweba with shared or per-frame palettes, dither control, frame differencing and a lossy threshold, all in its own GIF writer.
Animated GIFs are everywhere, and many of them are far bigger than they need to be. The format is old and limited, so getting good results depends on how the file is written. Paint by Zaweba has its own GIF writer for Export Animation, with control over palettes, dithering, frame differencing and lossy compression. Used well, those settings can cut a file size dramatically while keeping it looking clean.
Palettes: shared or per frame
A GIF frame can use at most 256 colours. Paint by Zaweba builds palettes using median cut, a method that picks colours to suit the picture. You choose between one shared palette for the whole animation or a separate palette for each frame.
A shared palette keeps colours consistent from frame to frame, which avoids flicker and is ideal when the scene doesn't change much, such as a logo animation or a UI demo. A per-frame palette lets each frame have the best colours for itself, which suits animations where the colours shift a lot, such as a clip that moves from a sunset to a night sky. It adds a little size, because each frame carries its own palette.
Dither choice and amount
Dithering scatters pixels to suggest colours the palette doesn't have, hiding banding in gradients and photos. You choose the dither method and how strongly it is applied.
More dither looks smoother but adds noise, and noise is hard to compress, so the file grows. Less dither gives smaller files but more banding. For flat graphics, little or no dither often looks best. For photographic content, a moderate amount usually wins. Try a few settings and compare at actual size.
Frame differencing
Frame differencing stores only the pixels that change from one frame to the next. In an animation where a small character moves across a still background, most of each frame is identical to the previous one, so differencing can save a great deal of space. It works best when the background is genuinely still. Camera shake, film grain or heavy dither on every frame make differencing less effective, because more pixels change.
Lossy threshold
The lossy threshold lets pixels that are very close in colour count as the same. That makes differencing find more unchanged areas and makes the compressor's job easier. A small threshold is usually invisible; a large one starts to smear detail. Raise it gradually and stop when you see artefacts.
A routine for small GIFs
Start by cutting what isn't needed: crop tightly, reduce the size to what will actually be shown, and trim unneeded frames in the Timeline. Then pick shared or per-frame palette depending on how much colour changes. Set dither low for graphics and moderate for photos. Leave frame differencing on. Finally, nudge the lossy threshold up until you are happy with the size and quality.
When GIF isn't the answer
For long clips or photographic video, GIF is rarely the best format. Animated WebP from the same Export Animation dialog keeps more colour at a smaller size where it is supported, and MP4 is far more efficient for anything longer than a few seconds, when the suite's FFmpeg is installed. Paint by Zaweba lets you export the same timeline to each, so you can compare and choose.
