Preserve native orthophoto detail for training

scripts/assemble_belgium_building_corpus.py

@@ -142,7 +142,12 @@ def main() -> int:
                 raster_path=raster_target,
                 source_name=reference_source,
                 min_label_px=args.min_label_px,
-                imagery_observed_at=raster.observed_at.isoformat() if raster.observed_at else None,
+                imagery_observed_at=(
+                    raster.observed_at.isoformat()
+                    if raster.observed_at
+                    and (raster.source_metadata or {}).get("observation_time_precision") != "unknown_per_pixel"
+                    else None
+                ),
                 reference_observed_at=reference.observed_at.isoformat() if reference.observed_at else None,
             )
             normalized_target.write_text(json.dumps(normalized, ensure_ascii=False), encoding="utf-8")

scripts/normalize_belgium_building_labels.py

@@ -160,10 +160,12 @@ def normalize(
             counts[str(decision["reason"])] += 1
 
     temporal_mismatch_days = None
+    temporal_alignment_status = "unknown"
     if imagery_observed_at and reference_observed_at:
         imagery_date = datetime.fromisoformat(imagery_observed_at.replace("Z", "+00:00"))
         reference_date = datetime.fromisoformat(reference_observed_at.replace("Z", "+00:00"))
         temporal_mismatch_days = abs((imagery_date - reference_date).days)
+        temporal_alignment_status = "measured"
     normalized = {
         "type": "FeatureCollection",
         "name": f"canonical-building-{source_name}",
@@ -179,6 +181,7 @@ def normalize(
         "imagery_observed_at": imagery_observed_at,
         "reference_observed_at": reference_observed_at,
         "temporal_mismatch_days": temporal_mismatch_days,
+        "temporal_alignment_status": temporal_alignment_status,
         "input_feature_count": len(payload["features"]),
         "accepted_feature_count": len(accepted),
         "decision_counts": dict(sorted(counts.items())),