npr op• データ種: image2d → pairs
• 呼び出し: import fullseye as fs; fs.ledger.mosaic_tiles_sites(image, n_tiles=400, iterations=12, seed=0, weighted=True) (実装を直接呼ぶなら import printpath; printpath.mosaic_tiles_sites(image, n_tiles=400, iterations=12, seed=0, weighted=True)、台帳から引くなら opsprintpath.get("mosaic_tiles_sites"))
Lloyd's iteration on an image — the tile centres of a mosaic.
Places *n_tiles* sites and moves each to the centroid of the pixels it owns, weighted by local contrast when *weighted* (so detail gets smaller tiles).
★Why this earns its place: Lloyd's iteration is a descent — the quantisation energy cannot increase — and that is a property of the algorithm, not of the picture. The energy is *not* reported here on purpose: the existing stipple_energy measures it from the sites, so the monotonicity can be checked by an op that did not produce them. Measuring your own descent with your own number proves nothing.
Returns pairs: the site coordinates (row, col).
Raises ValueError: fewer than 4 tiles or more tiles than pixels; negative iterations; a non-finite or oversized image.
• サンプルデータ カタログ(DL URL / ライセンス) — 2-D は skimage.data(BSD/public)+ 合成、3-D は実データ源(Stanford/PDS 等)の DL URL。
• 演算子の来歴・参考文献 — この op 族の元になった研究/手法の出典。
• アルゴリズムの正典(著者・年)と用途は上記ファミリ使い方ガイドに記載。
• poc_beats_fringes_and_screens — py -3.11 examples/poc_beats_fringes_and_screens.py
pairs を入力に取れる)stipple_energy · stroke_tour_closed · mst_length · stroke_resample_closed · stroke_tone_error · mosaic_tiles_render
npr)halftone_screen · halftone_moire_period · engrave_lines · hatch_field · mosaic_tiles_render
*Provenance: printpath.py — PRINTPATH operator registry. この per-op ノートは tools/opdocs.py md が自動生成(手編集しない)。*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.