Eden

Highlights

• A film driven by scroll, with no video player

  145 frames and as many alpha mattes, called by the scroll position, forwards and backwards. No video element in the page: the visitor's gesture is the only clock, and two stacked canvases take the background and the cut-out foreground.

• Everything is prepared off the main thread

  A worker decodes each pair, computes the bloom on it (luminance threshold, blur, screen blend, on a 960 px reduction), cuts out the foreground, then transfers two ImageBitmaps instead of copying them. The thread listening to the scroll does nothing but draw.

• Bounded memory, no catch-up jumps

  Twelve decoded pairs at most, the furthest ones closed explicitly. And the animation only advances when the next pair is ready: after a cache miss it resumes where it was instead of skipping ten frames at once.

• 15.3 MB for the whole sequence

  Down from 32.8 before re-encoding. WebP quality 74 for the frames, lossless for the alpha mattes, and a four-request parallel prefetch that decodes nothing on the way.

• Mattes tracked across all 145 frames

  The figures and their chairs come from a Resolve track, exported as two renders, one on white and one on black: subtracting them recovers the real opacity, edges included. Every visible colour still comes from the original shot.

• Static files, no dependency

  HTML, CSS, three scripts and a worker, published as they are, with no build step. The system's reduced-motion setting is respected: no drifting bloom, no preloading, the garden stays still.