ZOETROPE

r2 · GIF → ANIMATED SVG

A GIF goes in, one animated SVG comes out — every frame cut with LINEFINDER · DETAIL (the CHESHIRE r1 gates), switched with pure SMIL opacity. No script, no dependencies in the file it writes. r2: crop, up to every frame, grids to 448.

OPEN A GIF

tap here · or drop a .gif on the stage

TAP · PAUSE HOLD · SOURCE GIF

Waiting for a GIF.

— / —

FRAMES cap · past it the reel is thinned evenly · ALL keeps every unique frame

GRID working long side, px · 224 is the detail cut · 448 is four times the work

PALETTE k · AUTO sweeps 10 · 14 · 18, knee-picked

SPEED loop rate · re-emits without re-cutting

What it does. The GIF is decoded with REEL r2's parser (LZW, interlace, disposal 2 and 3, transparency); r2 decodes each frame when it is reached rather than up front, so a big reel costs its compressed size in memory and nothing more. Every kept frame is cut with LINEFINDER v3 exactly as CHESHIRE r1 cuts its DETAIL pass: a 224 px working grid (144 · 320 · 448 on offer), the palette swept 10 · 14 · 18 and knee-picked by LINEFINDER's own sanity check, regions down to five ten-thousandths of the frame allowed to live, Douglas-Peucker ε 0.8, no 90° snap. Two things change because it is an animation: the palette is fitted once across the whole reel so a colour lands on the same cluster in every frame, and the sweep is graded on three frames (first, middle, last).

Crop. Set on the source, in GIF pixels, and applied at the cut — the working grid goes to the crop, so a crop is also a sharper picture and a smaller file. Identical-frame merging is judged inside the crop too: a frame that only changes outside it is a hold.

Frames. Identical consecutive frames are merged into one hold. Past the cap the reel is thinned evenly by index and each kept frame inherits the time of the frames it stands in for, so the loop stays as long as the GIF; ALL keeps every unique frame. Delays under 20 ms read as 100 ms, the way browsers read them. The reel is walked twice — a scan that merges holds, samples the palette and keeps a handful of probe frames for the k sweep, then the cut — and nothing but the cut shapes is kept between frames. The scan is kept while the crop and grid stay the same, so changing FRAMES or PALETTE skips straight to the cut.

The file it writes. One <g> per frame, each carrying a single <animate attributeName="opacity" calcMode="discrete"> that turns it on for its slice of the loop, repeatCount="indefinite". Frames after the first start at opacity 0, so a viewer with no SMIL shows frame 1 as a still. Width and height are the crop's pixels; the viewBox is the working grid. Playback here is the same file, inline — pause, step and scrub drive the SVG's own timeline. Size is linear in frames and roughly linear in grid area; the readout tells you before you save.