Merge pull request #621 from roboflow/nick/bug-fix/detection-offset-n…

…ull-images

Fix Detection Offset Bug

inference/core/workflows/core_steps/transformations/detection_offset/v1.py

@@ -134,15 +134,16 @@ def offset_detections(
     if len(detections) == 0:
         return detections
     _detections = deepcopy(detections)
+    image_dimensions = detections.data["image_dimensions"]
     _detections.xyxy = np.array(
         [
             (
-                x1 - offset_width // 2,
-                y1 - offset_height // 2,
-                x2 + offset_width // 2,
-                y2 + offset_height // 2,
+                max(0, x1 - offset_width // 2),
+                max(0, y1 - offset_height // 2),
+                min(image_dimensions[i][1], x2 + offset_width // 2),
+                min(image_dimensions[i][0], y2 + offset_height // 2),
             )
-            for (x1, y1, x2, y2) in _detections.xyxy
+            for i, (x1, y1, x2, y2) in enumerate(_detections.xyxy)
         ]
     )
     _detections[parent_id_key] = detections[detection_id_key].copy()

tests/workflows/unit_tests/core_steps/transformations/test_detection_offset.py

@@ -85,6 +85,7 @@ def test_offset_detection() -> None:
             "detection_id": np.array(["two"]),
             "class_name": np.array(["car"]),
             "parent_id": np.array(["p2"]),
+            "image_dimensions": np.array([[640, 640]]),
         },
     )
 
@@ -108,6 +109,42 @@ def test_offset_detection() -> None:
         detections["parent_id"][0]
     ), "New detection id (random) must be assigned"
 
+def test_offset_detection_when_larger_than_image() -> None:
+    # given
+    detections = sv.Detections(
+        xyxy=np.array([[90, 190, 110, 210]], dtype=np.float64),
+        class_id=np.array([1]),
+        confidence=np.array([0.5], dtype=np.float64),
+        data={
+            "detection_id": np.array(["two"]),
+            "class_name": np.array(["car"]),
+            "parent_id": np.array(["p2"]),
+            "image_dimensions": np.array([[640, 640]]),
+        },
+    )
+
+    # when
+    result = offset_detections(
+        detections=detections,
+        offset_width=2000,
+        offset_height=2000,
+    )
+
+    # then
+    x1, y1, x2, y2 = result.xyxy[0]
+    assert x1 == 0, "Left corner should be at the image border"
+    assert y1 == 0, "Top corner should be at the image border"
+    assert x2 == 640, "Right corner should be at the image border"
+    assert y2 == 640, "Bottom corner should be at the image border"
+    assert result["parent_id"] == str(
+        detections["detection_id"][0]
+    ), "Parent id should be set to origin detection id"
+    assert result["detection_id"] != str(
+        detections["parent_id"][0]
+    ), "New detection id (random) must be assigned"
+
+
+
 
 def test_offset_detection_when_nothing_predicted() -> None:
     # given