2026-09-24 17:04:33 +02:00
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# DESIGN — Fractal mosaic Python engine (Tower)
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## Goal
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Headless RST collage generator for the Tower mosaik inbox, adapted from Seth Benton’s Fractal-Mosaics (GPL).
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## Pipeline
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1. Load tile pool; cache mean RGB + HSV histogram (CBIR prefilter).
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2. Resize master to profile `master_max`.
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3. For each tile size (largest first), scan uncovered centers.
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4. Rank tiles by histogram/mean distance (**selection only — no recolor**).
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5. Estimate rotation/scale via log-polar phase correlation; snap to discrete rot/scale candidates.
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6. Place with edge alpha blend if RMS and overlap pass thresholds.
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7. Write PNG.
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## Profiles
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See `src/fractal_mosaic/profiles.py`: `wenig`, `mittel`, `dicht`.
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2026-09-29 00:38:02 +02:00
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## Coverage
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Profiles target ~99% canvas coverage via denser RST passes + residual fill, while
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keeping Fractal RST (rotation / scale / translate) — not a classic grid mosaic.
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Pool images may be reused heavily when the library is small.
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## Tile size (readability)
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Piece sizes stay in a recognizable absolute range while `master_max` is high so
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the canvas holds many pieces. Relative density ladder (largest tile / master):
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wenig ≈1.75%, mittel ≈1.3%, dicht ≈1.0%. `max_placements` scales with
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`(master_max / mean_tile)^2` so each profile can still hit ~99% coverage.
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Scales never enlarge above 1.0.
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2026-09-24 17:04:33 +02:00
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## Non-goals (v1)
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- Faithful bit-identical MATLAB port
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- Color transfer / hue variants
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- GPU acceleration
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