feat: add fixed_zone param to pipelines, skip truck detection when set

src/pipeline.py

@@ -20,7 +20,7 @@ from src.interfaces import Detection
 from src.model_registry import ModelConfig
 from src.stabilizer import BboxStabilizer
 from src.tracking import ByteTrackTracker
-from src.truck_roi import TruckROITracker
+from src.truck_roi import TruckROI, TruckROITracker
 from src.video_writer import AnnotatedVideoWriter
 
 
@@ -78,6 +78,7 @@ def run_pipeline(
     output_path: str,
     class_filter: list[str] | None = None,
     truck_model_config: ModelConfig | None = None,
+    fixed_zone: TruckROI | None = None,
     sack_conf: float = 0.4,
     truck_conf: float = 0.5,
     truck_det_interval: int = 15,
@@ -143,17 +144,18 @@ def run_pipeline(
         shared_model, conf=sack_conf, class_filter=effective_filter
     )
 
-    # Truck detector: use explicit truck_model_config, or same model if it has "truck" class
+    # Truck detector — skip if fixed zone
     truck_detector = None
-    if truck_model_config is not None:
+    if fixed_zone is None:
-        # Load a separate truck detection model
+        if truck_model_config is not None:
-        truck_shared = YOLO(truck_model_config.path)
+            # Load a separate truck detection model
-        truck_detector = BaseDetector(truck_shared, conf=truck_conf, class_filter=("truck",))
+            truck_shared = YOLO(truck_model_config.path)
-    elif "truck" in (model_config.known_classes or []):
+            truck_detector = BaseDetector(truck_shared, conf=truck_conf, class_filter=("truck",))
-        # Use the same model for truck detection
+        elif "truck" in (model_config.known_classes or []):
-        truck_detector = BaseDetector(
+            # Use the same model for truck detection
-            shared_model, conf=truck_conf, class_filter=("truck",)
+            truck_detector = BaseDetector(
-        )
+                shared_model, conf=truck_conf, class_filter=("truck",)
+            )
 
     tracker = ByteTrackTracker(shared_model, conf=sack_conf)
     stabilizer = BboxStabilizer()
@@ -199,10 +201,13 @@ def run_pipeline(
                 break
 
             # Truck detection
-            roi = roi_tracker.roi
+            if fixed_zone is not None:
-            if truck_detector is not None and frame_idx % truck_det_interval == 0:
+                roi = fixed_zone
-                trucks = truck_detector.detect(frame)
+            else:
-                roi = roi_tracker.update(trucks)
+                roi = roi_tracker.roi
+                if truck_detector is not None and frame_idx % truck_det_interval == 0:
+                    trucks = truck_detector.detect(frame)
+                    roi = roi_tracker.update(trucks)
 
             truck_present = roi is not None and roi.confidence > 0
 
@@ -362,6 +367,7 @@ def run_merged_pipeline(
     output_path: str,
     class_filters: dict[str, list[str] | None] | None = None,
     truck_model_config: ModelConfig | None = None,
+    fixed_zone: TruckROI | None = None,
     sack_conf: float = 0.4,
     truck_conf: float = 0.5,
     truck_det_interval: int = 15,
@@ -399,17 +405,18 @@ def run_merged_pipeline(
         eff_filter = (class_filters or {}).get(cfg.stem) or cfg.known_classes or None
         detectors.append(BaseDetector(model, conf=sack_conf, class_filter=eff_filter))
 
-    # Truck detector
+    # Truck detector — skip if fixed zone
     truck_det = None
-    if truck_model_config is not None:
+    if fixed_zone is None:
-        truck_shared = YOLO(truck_model_config.path)
+        if truck_model_config is not None:
-        truck_det = BaseDetector(truck_shared, conf=truck_conf, class_filter=("truck",))
+            truck_shared = YOLO(truck_model_config.path)
-    # ponytail: first-match truck detector; could prefer dedicated truck model over sack model w/ truck class
+            truck_det = BaseDetector(truck_shared, conf=truck_conf, class_filter=("truck",))
-    else:
+        # ponytail: first-match truck detector; could prefer dedicated truck model over sack model w/ truck class
-        for i, cfg in enumerate(model_configs):
+        else:
-            if "truck" in (cfg.known_classes or []):
+            for i, cfg in enumerate(model_configs):
-                truck_det = detectors[i]
+                if "truck" in (cfg.known_classes or []):
-                break
+                    truck_det = detectors[i]
+                    break
 
     # Single tracker using first model's weights
     tracker_model = YOLO(model_configs[0].path)
@@ -453,10 +460,13 @@ def run_merged_pipeline(
                 break
 
             # Truck detection
-            roi = roi_tracker.roi
+            if fixed_zone is not None:
-            if truck_det is not None and frame_idx % truck_det_interval == 0:
+                roi = fixed_zone
-                trucks = truck_det.detect(frame)
+            else:
-                roi = roi_tracker.update(trucks)
+                roi = roi_tracker.roi
+                if truck_det is not None and frame_idx % truck_det_interval == 0:
+                    trucks = truck_det.detect(frame)
+                    roi = roi_tracker.update(trucks)
 
             truck_present = roi is not None and roi.confidence > 0
             if roi is not None:

tests/test_fixed_zone_pipeline.py

@@ -0,0 +1,27 @@
+"""Tests for fixed_zone parameter in pipeline functions."""
+
+import inspect
+
+from src.pipeline import run_pipeline, run_merged_pipeline
+
+
+def test_run_pipeline_accepts_fixed_zone():
+    sig = inspect.signature(run_pipeline)
+    assert "fixed_zone" in sig.parameters
+
+
+def test_run_merged_pipeline_accepts_fixed_zone():
+    sig = inspect.signature(run_merged_pipeline)
+    assert "fixed_zone" in sig.parameters
+
+
+def test_fixed_zone_defaults_to_none():
+    sig = inspect.signature(run_pipeline)
+    param = sig.parameters["fixed_zone"]
+    assert param.default is None
+
+
+def test_merged_fixed_zone_defaults_to_none():
+    sig = inspect.signature(run_merged_pipeline)
+    param = sig.parameters["fixed_zone"]
+    assert param.default is None