fix:distance consistency

LaserPerception/LaserPerception.js

@@ -2644,10 +2644,26 @@
 
                 tr.label = best.label || tr.label;
                 tr.score = best.score || tr.score;
+
+                // Depth smoothing with hysteresis
                 if (best.depth_valid && Number.isFinite(best.depth_est_m)) {
-                    tr.depth_est_m = best.depth_est_m;
+                    // EMA smoothing
+                    if (tr.depth_est_m == null) {
+                        tr.depth_est_m = best.depth_est_m;
+                    } else {
+                        tr.depth_est_m = lerp(tr.depth_est_m, best.depth_est_m, 0.35);
+                    }
                     tr.depth_rel = Number.isFinite(best.depth_rel) ? best.depth_rel : tr.depth_rel;
                     tr.depth_valid = true;
+                    tr.lastDepthTime = now();
+                } else {
+                    // Hysteresis: hold last valid depth for 0.8s
+                    if (tr.lastDepthTime && (now() - tr.lastDepthTime) < 800) {
+                        // keep existing tr.depth_est_m
+                    } else {
+                        tr.depth_valid = false;
+                        tr.depth_est_m = null; // fallback to area
+                    }
                 }
                 tr.lastSeen = now();
             }

inference.py

@@ -246,7 +246,20 @@ def _attach_depth_metrics(
         y2 = max(y1 + 1, min(height, y2))
 
         patch = depth_map[y1:y2, x1:x2]
-        finite = patch[np.isfinite(patch)]
+        if patch.size == 0:
+            continue
+            
+        # Center crop (50%) to avoid background
+        h_p, w_p = patch.shape
+        cy, cx = h_p // 2, w_p // 2
+        dy, dx = h_p // 4, w_p // 4
+        center_patch = patch[cy - dy : cy + dy, cx - dx : cx + dx]
+        
+        # Fallback to full patch if center is empty (unlikely)
+        if center_patch.size == 0:
+           center_patch = patch
+
+        finite = center_patch[np.isfinite(center_patch)]
         if finite.size == 0:
             continue