fix: car detection use wrong image source

core/tracking/integration.py

@@ -350,10 +350,21 @@ class TrackingPipelineIntegration:
                     'session_id': session_id
                 }
 
+            # Fetch high-quality 2K snapshot for detection phase (not RTSP frame)
+            # This ensures bbox coordinates match the frame used in processing phase
+            logger.info(f"[DETECTION PHASE] Fetching 2K snapshot for vehicle {vehicle.track_id}")
+            snapshot_frame = self._fetch_snapshot()
+
+            if snapshot_frame is None:
+                logger.warning(f"[DETECTION PHASE] Failed to fetch snapshot, falling back to RTSP frame")
+                snapshot_frame = frame  # Fallback to RTSP if snapshot fails
+            else:
+                logger.info(f"[DETECTION PHASE] Using {snapshot_frame.shape[1]}x{snapshot_frame.shape[0]} snapshot for detection")
+
             # Execute only the detection phase (first phase)
             # This will run detection and send imageDetection message to backend
             detection_result = await self.detection_pipeline.execute_detection_phase(
-                frame=frame,
+                frame=snapshot_frame,  # Use 2K snapshot instead of RTSP frame
                 display_id=display_id,
                 subscription_id=subscription_id
             )
@@ -373,13 +384,13 @@ class TrackingPipelineIntegration:
             if detection_result['message_sent']:
                 # Store for later processing when sessionId is received
                 self.pending_processing_data[display_id] = {
-                    'frame': frame.copy(),  # Store copy of frame for processing phase
+                    'frame': snapshot_frame.copy(),  # Store copy of 2K snapshot (not RTSP frame!)
                     'vehicle': vehicle,
                     'subscription_id': subscription_id,
                     'detection_result': detection_result,
                     'timestamp': time.time()
                 }
-                logger.info(f"Stored processing data for {display_id}, waiting for sessionId from backend")
+                logger.info(f"Stored processing data ({snapshot_frame.shape[1]}x{snapshot_frame.shape[0]} frame) for {display_id}, waiting for sessionId from backend")
 
             return detection_result
 
@@ -413,14 +424,27 @@ class TrackingPipelineIntegration:
 
             logger.info(f"Executing processing phase for session {session_id}, vehicle {vehicle.track_id}")
 
-            # Capture high-quality snapshot for pipeline processing
-            logger.info(f"[PROCESSING PHASE] Fetching 2K snapshot for session {session_id}")
-            frame = self._fetch_snapshot()
+            # Reuse the snapshot from detection phase OR fetch fresh one if detection used RTSP fallback
+            detection_frame = processing_data['frame']
+            frame_height = detection_frame.shape[0]
 
-            if frame is None:
-                logger.warning(f"[PROCESSING PHASE] Failed to capture snapshot, falling back to RTSP frame")
-                # Fall back to RTSP frame if snapshot fails
-                frame = processing_data['frame']
+            # Check if detection phase used 2K snapshot (height > 1000) or RTSP fallback (height = 720)
+            if frame_height >= 1000:
+                # Detection used 2K snapshot - reuse it for consistent coordinates
+                logger.info(f"[PROCESSING PHASE] Reusing 2K snapshot from detection phase ({detection_frame.shape[1]}x{detection_frame.shape[0]})")
+                frame = detection_frame
+            else:
+                # Detection used RTSP fallback - need to fetch fresh 2K snapshot
+                logger.warning(f"[PROCESSING PHASE] Detection used RTSP fallback ({detection_frame.shape[1]}x{detection_frame.shape[0]}), fetching fresh 2K snapshot")
+                frame = self._fetch_snapshot()
+
+                if frame is None:
+                    logger.error(f"[PROCESSING PHASE] Failed to fetch snapshot and detection used RTSP - coordinate mismatch will occur!")
+                    logger.error(f"[PROCESSING PHASE] Cannot proceed with mismatched coordinates. Aborting processing phase.")
+                    return  # Cannot process safely - bbox coordinates won't match frame resolution
+                else:
+                    logger.warning(f"[PROCESSING PHASE] Fetched fresh 2K snapshot ({frame.shape[1]}x{frame.shape[0]}), but coordinates may not match exactly")
+                    logger.warning(f"[PROCESSING PHASE] Re-running detection on fresh snapshot is recommended but not implemented yet")
 
             # Extract detected regions from detection phase result if available
             detected_regions = detection_result.get('detected_regions', {})