Sliced Wasserstein embeddings + HNSW for color-scheme search over 48k paintings [P]

Palette Atlas (https://itzik123.github.io/PaletteAtlas/) searches public-domain paintings by color scheme. Each image is reduced to 128 colors of equal weight, so the natural distance is the Earth Mover's Distance, which is too slow for nearest-neighbor search over 48,695 items (about 6 ms per…