Gate YOLO tile labels by visible ratio

scripts/export_operator_yolo_tile_dataset.py

@@ -78,6 +78,15 @@ def parse_args() -> argparse.Namespace:
         default=float(os.environ.get("OPERATOR_YOLO_MIN_LABEL_PX", "4")),
         help="Minimum clipped box width/height in pixels before a tile label is kept.",
     )
+    parser.add_argument(
+        "--min-label-visible-ratio",
+        type=float,
+        default=float(os.environ.get("OPERATOR_YOLO_MIN_LABEL_VISIBLE_RATIO", "0")),
+        help=(
+            "Minimum visible share of the original object bbox required before a clipped tile label is kept. "
+            "Use 0 to keep legacy edge-fragment labels."
+        ),
+    )
     parser.add_argument(
         "--background-negative-repeat",
         type=int,
@@ -217,7 +226,7 @@ def load_reference_pixel_boxes(reference_path: Path, dataset: Any, min_label_px:
     return boxes
 
 
-def labels_for_tile(tile_window: TileWindow, boxes: list[PixelBox], min_label_px: float) -> list[str]:
+def labels_for_tile(tile_window: TileWindow, boxes: list[PixelBox], min_label_px: float, min_visible_ratio: float = 0.0) -> list[str]:
     labels: list[str] = []
     tile_min_col = tile_window.col_off
     tile_min_row = tile_window.row_off
@@ -233,6 +242,11 @@ def labels_for_tile(tile_window: TileWindow, boxes: list[PixelBox], min_label_px
         box_height = max_row - min_row
         if box_width < min_label_px or box_height < min_label_px:
             continue
+        original_area = max((box.max_col - box.min_col) * (box.max_row - box.min_row), 0.0)
+        visible_area = box_width * box_height
+        visible_ratio = visible_area / original_area if original_area > 0 else 0.0
+        if min_visible_ratio > 0 and visible_ratio < min_visible_ratio:
+            continue
         local_min_col = min_col - tile_min_col
         local_max_col = max_col - tile_min_col
         local_min_row = min_row - tile_min_row
@@ -296,6 +310,7 @@ def export_sample_tiles(
     stride: int,
     negative_keep_ratio: float,
     min_label_px: float,
+    min_label_visible_ratio: float,
     background_negative_repeat: int,
 ) -> list[dict[str, Any]]:
     sample_slug = str(sample["sample_slug"])
@@ -312,7 +327,12 @@ def export_sample_tiles(
     with rasterio.open(raster_path) as dataset:
         boxes = load_reference_pixel_boxes(reference_path, dataset, min_label_px=min_label_px)
         for tile_index, tile_window in enumerate(iter_tile_windows(dataset.width, dataset.height, tile_size, stride)):
-            labels = labels_for_tile(tile_window, boxes, min_label_px=min_label_px)
+            labels = labels_for_tile(
+                tile_window,
+                boxes,
+                min_label_px=min_label_px,
+                min_visible_ratio=min_label_visible_ratio,
+            )
             is_negative = not labels
             if is_negative and not keep_negative_tile(sample_slug, tile_index, negative_keep_ratio):
                 exported.append(
@@ -391,6 +411,7 @@ def main() -> int:
                 stride=args.stride,
                 negative_keep_ratio=args.negative_keep_ratio,
                 min_label_px=args.min_label_px,
+                min_label_visible_ratio=args.min_label_visible_ratio,
                 background_negative_repeat=args.background_negative_repeat,
             )
         )
@@ -414,6 +435,7 @@ def main() -> int:
         "negative_keep_ratio": args.negative_keep_ratio,
         "background_negative_repeat": args.background_negative_repeat,
         "min_label_px": args.min_label_px,
+        "min_label_visible_ratio": args.min_label_visible_ratio,
         "source_sample_count": len(samples),
         "tile_count": len(kept_tiles),
         "positive_tile_count": len(positive_tiles),