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rpotter6298 35cbd9ac3c 2026001
2026-07-01 17:35:58 +02:00

252 lines
9.4 KiB
Python

#!/usr/bin/env python3
"""
validate_siamese.py — Validate the trained siamese network against Task06
held-out test patients.
Runs both connected-components and edge-ranking clustering (known K) on the
test set and reports metrics + assignment heatmaps.
Usage:
conda activate fundus_imaging
python scripts/clustering_validation/validate_siamese.py
python scripts/clustering_validation/validate_siamese.py --threshold 0.95 --tag v2
"""
import os, sys, json, argparse
import numpy as np
import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt
os.environ["OMP_NUM_THREADS"] = "1"
os.environ["OPENBLAS_NUM_THREADS"] = "1"
os.environ["MKL_NUM_THREADS"] = "1"
sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.dirname(
os.path.abspath(__file__)))))
from classes import SiamesePatientMatcher
from sklearn.metrics import adjusted_rand_score, normalized_mutual_info_score
ROOT = os.path.dirname(os.path.dirname(os.path.dirname(
os.path.abspath(__file__))))
MODELS_DIR = os.path.join(ROOT, "models")
RESULTS_DIR = os.path.join(ROOT, "results", "clustering_validation")
PLOTS_DIR = os.path.join(ROOT, "plots")
PNG_DIR = os.path.join(ROOT, "features", "task06_pngs", "test")
VOLUME_DIR = os.path.join(os.path.dirname(ROOT), "Task06_Lung", "imagesTr")
SEED = 42
# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------
def cluster_purity_stats(y_true, y_pred):
purities = []
overall_correct = 0
for c in np.unique(y_pred):
mask = y_pred == c
_, counts = np.unique(y_true[mask], return_counts=True)
purities.append(counts.max() / mask.sum())
overall_correct += counts.max()
purities = np.array(purities)
return {
"overall": float(overall_correct / len(y_true)),
"median": float(np.median(purities)),
"mean": float(np.mean(purities)),
"frac_gt_70": float((purities > 0.7).mean()),
"frac_gt_90": float((purities > 0.9).mean()),
}
def patient_capture_stats(y_true, y_pred):
captures = []
for p in np.unique(y_true):
mask = y_true == p
p_clusters = y_pred[mask]
_, counts = np.unique(p_clusters, return_counts=True)
captures.append(counts.max() / mask.sum())
captures = np.array(captures)
return {
"median": float(np.median(captures)),
"mean": float(np.mean(captures)),
"frac_gt_50": float((captures > 0.5).mean()),
}
def score_manifest(manifest, y_true_map):
"""Score a manifest against ground-truth patient IDs."""
preds, truths = [], []
for pred_pid, fnames in manifest.items():
for f in fnames:
preds.append(pred_pid)
truths.append(y_true_map.get(f, f"unknown_{f}"))
y_true = np.array(truths)
y_pred = np.array(preds)
purity = cluster_purity_stats(y_true, y_pred)
capture = patient_capture_stats(y_true, y_pred)
ari = adjusted_rand_score(y_true, y_pred)
nmi = normalized_mutual_info_score(y_true, y_pred)
return {"ARI": ari, "NMI": nmi,
"cluster_purity": purity, "patient_capture": capture,
"y_true": y_true, "y_pred": y_pred}
def plot_assignment_matrix(y_true, y_pred, out_path, title):
true_patients = sorted(np.unique(y_true))
pred_clusters = sorted(np.unique(y_pred))
matrix = np.zeros((len(true_patients), len(pred_clusters)))
for i, p in enumerate(true_patients):
for j, c in enumerate(pred_clusters):
matrix[i, j] = ((y_true == p) & (y_pred == c)).sum()
matrix_norm = matrix / (matrix.sum(axis=1, keepdims=True) + 1e-8)
fig, ax = plt.subplots(figsize=(max(14, len(pred_clusters) * 0.22),
max(10, len(true_patients) * 0.18)))
cmap = plt.cm.YlOrRd.copy()
cmap.set_under('white')
im = ax.imshow(matrix_norm, aspect="auto", cmap=cmap, vmin=1e-6, vmax=1)
ax.set_xticks(range(len(pred_clusters)))
ax.set_xticklabels([f"c{c}" for c in pred_clusters], fontsize=6, rotation=90)
ax.set_yticks(range(len(true_patients)))
ax.set_yticklabels(true_patients, fontsize=7)
ax.set_xlabel("Predicted cluster"); ax.set_ylabel("True patient")
ax.set_title(title, fontsize=11)
plt.colorbar(im, ax=ax, label="Fraction of patient's slices")
plt.tight_layout()
os.makedirs(os.path.dirname(out_path), exist_ok=True)
plt.savefig(out_path, dpi=150)
plt.close()
print(f" Heatmap → {out_path}")
# ---------------------------------------------------------------------------
# Main
# ---------------------------------------------------------------------------
def main():
ap = argparse.ArgumentParser()
ap.add_argument("--model", default=os.path.join(MODELS_DIR, "siamese_resnet18.pt"))
ap.add_argument("--backbone", default="resnet18")
ap.add_argument("--threshold", type=float, default=0.9)
ap.add_argument("--tag", default="", help="Append tag to output filenames")
ap.add_argument("--full", action="store_true",
help="Run on full NIfTI dataset (leaked training data).")
args = ap.parse_args()
tag = f"_{args.tag}" if args.tag else ""
os.makedirs(RESULTS_DIR, exist_ok=True)
os.makedirs(PLOTS_DIR, exist_ok=True)
# ---- Load test PNGs ----
if args.full:
tag = (tag or "") + "_full"
from classes import NiftiSliceDataset
VOL = os.path.join(os.path.dirname(ROOT), "Task06_Lung", "imagesTr")
ds = NiftiSliceDataset(VOL, random_slices=False, seed=SEED, rotate_deg=90)
ds.load_all_slices(stride=1)
# Export full PNGs to temp dir
import tempfile
tmpdir = tempfile.mkdtemp(prefix="task06_full_")
full_paths, full_pids, _ = ds.export_pngs(tmpdir)
test_paths = full_paths
test_pids = np.array(full_pids)
print(f" FULL dataset: {len(test_paths)} slices, {len(np.unique(test_pids))} patients")
print(f" (includes training data — leakage expected for siamese)")
else:
manifest_path = os.path.join(PNG_DIR, "manifest.json")
if not os.path.exists(manifest_path):
print(f"Test PNGs not found at {PNG_DIR}")
print("Run train_siamese.py first to generate the test set.")
sys.exit(1)
with open(manifest_path) as f:
png_manifest = json.load(f)
test_paths = png_manifest["paths"]
test_pids = np.array(png_manifest["patient_ids"])
# Short filenames for matching
test_fnames = [p.split("/")[-1].replace(".png", "") for p in test_paths]
y_true_map = {f: pid for f, pid in zip(test_fnames, test_pids)}
k = len(np.unique(test_pids))
print("=" * 60)
print(f"Siamese validation — held-out test set")
print("=" * 60)
print(f" {len(test_paths)} slices, {k} patients")
print(f" Model: {args.model}")
# ---- Load siamese model ----
print(f"\nLoading siamese model ...")
matcher = SiamesePatientMatcher(
args.model, backbone=args.backbone, input_size=224)
# ---- Connected components (no known K) ----
print(f"\n{''*50}")
print("Method 1: Connected components (threshold-based)")
print(f"{''*50}")
manifest_cc = matcher.identify_patients(
test_paths, filenames=test_fnames,
threshold=args.threshold, top_k=20, k=None)
# ---- Edge-ranking clustering (known K) ----
print(f"\n{''*50}")
print(f"Method 2: Edge-ranking clustering (k={k})")
print(f"{''*50}")
manifest_sc = matcher.identify_patients(
test_paths, filenames=test_fnames,
threshold=args.threshold, top_k=20, k=k)
# ---- Score both methods ----
results_cc = score_manifest(manifest_cc, y_true_map)
results_sc = score_manifest(manifest_sc, y_true_map)
print(f"\n{'='*60}")
print("RESULTS — Siamese patient identification")
print(f"{'='*60}")
print(f"\n{'Method':<30s} {'ARI':>7s} {'NMI':>7s} {' Purity Capture':>8s}")
print(f"{'':30s} {'':>7s} {'':>7s} {' (overall) (mean) ':>8s}")
print("-" * 60)
for name, r in [("Connected components", results_cc),
("Edge ranking (k=" + str(k) + ")", results_sc)]:
p = r["cluster_purity"]["overall"]
c = r["patient_capture"]["mean"]
print(f"{name:<30s} {r['ARI']:>7.3f} {r['NMI']:>7.3f} "
f"{p:>7.1%} {c:>7.1%}")
# ---- Save metrics ----
for suffix, r in [("cc", results_cc), ("sc", results_sc)]:
out = {k: v for k, v in r.items() if k not in ("y_true", "y_pred")}
out["method"] = suffix
out["threshold"] = args.threshold
out["n_patients"] = int(k)
out["n_slices"] = len(test_paths)
out_json = os.path.join(RESULTS_DIR, f"validate_siamese_{suffix}{tag}.json")
with open(out_json, "w") as f:
json.dump(out, f, indent=2)
print(f" Metrics → {out_json}")
# ---- Plot siamese methods ----
for name, r in [("connected_components", results_cc),
("edge_rank", results_sc)]:
p = r["cluster_purity"]["overall"]
c = r["patient_capture"]["mean"]
title = (f"Siamese Patient-Cluster Assignment ({name})\n"
f"(ARI={r['ARI']:.3f}, purity={p:.1%}, "
f"capture mean={c:.1%})")
plot_assignment_matrix(
r["y_true"], r["y_pred"],
os.path.join(PLOTS_DIR, "clustering_validation", "siamese",
f"assignment_matrix_{name}{tag}.png"),
title)
print("DONE")
if __name__ == "__main__":
main()