ShapeAR: Generating Editable Shape Layers via Autoregressive Diffusion

摘要

We present ShapeAR, a novel autoregressive latent diffusion framework that decomposes raster images into editable, artist-like vector shape layers. Unlike conventional raster-to-SVG methods that rely on boundary tracing or joint path optimisation, ShapeAR generates non-overlapping RGBA shape layers directly in latent space via flow-matching diffusion. To scale generation to complex scenes with many shapes, we formulate the process auto-regressively, conditioning each step on both the input image (global context) and partial composition of previously generated layers (local context). In addition, we propose geometry-aware evaluation metrics that quantify aesthetic and structural quality of the generated shapes.