PeCA: Palette Context Assisted Inference for Test-Time Paint-Bucket Colourisation on Animation Videos

In animation production, paint-bucket colourisation for hand-drawn animation is a labour-intensive procedure that assigns each en-closed region in line sketches a colour from reference design sheets. Re-cent automatic paint-bucket colourisation pipelines mirror this workflowvia region correspondence, but correspondences can be brittle when re-gions are ambiguous fragments without proper context. In this paper,we propose Palette Context Assisted (PeCA), a new training-free, plug-and-play framework for animation video colourisation that aims to closethis gap at test-time via reasoning over spatial and temporal contexts.Extensive experiments on existing benchmarks and a newly introducedlong-video test case show consistent performance boosts.