Aseprite Inference

An .ase/.aseprite file is a structured timeline of layered pixel (or tilemap) cels. Read and verify the file rather than hard-coding expectations; output what you know and what you assumed.

Before inferring, ask:

• Authoring intent (tags/slices/user data) or render intent (visible pixels/bounds/ordering)?
• Do you need pixels (decompress cel images), or is structure-only (layers/timing/tags) enough?
• Is the sprite RGBA / Grayscale / Indexed / Tilemap — and does that change transparency/bounds logic?

Core principles

1. Chunk-driven: skip unknown chunks by chunk_size, don't crash.
2. Per-frame timing: header.speed is deprecated; each frame has its own duration (fallback to speed only when a frame duration is 0).
3. Separate decode modes: fast metadata pass first; pixel/tile decode only when needed.

Quick Start

Turn a file into JSON — needs nothing but node: