"""
Anatomy label tables and color assignments for the legend overlay.
CT labels are loaded directly from the upstream config so we stay in sync.
A deterministic golden-ratio HSV walk maps each label ID to a distinguishable RGB.
"""
from __future__ import annotations
import colorsys
import json
from pathlib import Path
ROOT = Path(__file__).resolve().parent.parent
UPSTREAM_LABEL_DICT = ROOT / "repos" / "NV-Generate-CTMR" / "configs" / "label_dict.json"
def _load_ct_labels() -> dict[int, str]:
if not UPSTREAM_LABEL_DICT.exists():
return {}
raw: dict[str, int] = json.loads(UPSTREAM_LABEL_DICT.read_text())
return {int(v): k for k, v in raw.items() if not k.startswith("dummy")}
def _color_for(idx: int) -> tuple[int, int, int]:
"""Deterministic high-contrast color from an integer ID."""
golden = 0.61803398875
h = (idx * golden) % 1.0
s = 0.55 + 0.35 * ((idx * 7) % 5) / 4.0
v = 0.70 + 0.25 * ((idx * 11) % 4) / 3.0
r, g, b = colorsys.hsv_to_rgb(h, s, v)
return int(r * 255), int(g * 255), int(b * 255)
CT_LABELS_BY_ID: dict[int, str] = _load_ct_labels()
def color_table(label_ids: list[int]) -> list[tuple[int, int, int, int]]:
"""RGBA palette for niivue label overlay — index 0 is background (transparent)."""
if not label_ids:
return []
max_id = max(label_ids)
palette: list[tuple[int, int, int, int]] = [(0, 0, 0, 0)]
for i in range(1, max_id + 1):
if i in label_ids:
r, g, b = _color_for(i)
palette.append((r, g, b, 200))
else:
palette.append((0, 0, 0, 0))
return palette
def legend_html(used_labels: dict[int, str]) -> str:
"""Compact horizontal legend showing only labels present in the generated mask."""
if not used_labels:
return ""
rows: list[str] = []
for lbl, name in sorted(used_labels.items()):
r, g, b = _color_for(lbl)
rows.append(
f'