Debug unreachable centres as gray

app.py

@@ -444,10 +444,6 @@ def _pipeline(uid,img_path):
     seg = cv2.resize(seg_tensor.numpy(), (640, 640), interpolation=cv2.INTER_NEAREST)
     print(f"🧪 [{uid}] segmentation input shape: {inputs['pixel_values'].shape}")
     water_mask, garbage_mask, movable_mask = build_masks(seg) # movable zone = water and garbage masks
-    for cx, cy in centres:
-        cv2.circle(movable_mask, (cx, cy), 3, 127, -1)  # gray center dots
-    cv2.imwrite(f"{OUTPUT_DIR}/{uid}_movable_with_centres.png", movable_mask * 255)
-    print(f"🧩 Saved debug movable_mask: {OUTPUT_DIR}/{uid}_movable_mask.png")
 
     # 2- Garbage detection (3 models) → keep centres on water 
     detections=[]
@@ -493,6 +489,11 @@ def _pipeline(uid,img_path):
     # add chunk centres and deduplicate
     centres.extend(chunk_centres)
     centres = [list(c) for c in {tuple(c) for c in centres}]
+    for cx, cy in centres:
+        cv2.circle(movable_mask, (cx, cy), 3, 127, -1)  # gray center dots
+    cv2.imwrite(f"{OUTPUT_DIR}/{uid}_movable_with_centres.png", movable_mask * 255)
+    print(f"🧩 Saved debug movable_mask: {OUTPUT_DIR}/{uid}_movable_mask.png")
+
     if not centres: # No garbages within travelable zone
         print(f"🛑 [{uid}] no reachable garbage"); video_ready[uid]=True; return
     else: # Garbage within valid travelable zone