Use generic loader

Author: lochhh

poseinterface/io.py

@@ -1,35 +1,66 @@
 from pathlib import Path
+import sleap_io as sio
+from sleap_io.io import dlc
 
-from sleap_io.io import coco, dlc
 
-
-def format_dlc_annotations_file(
+_EMPTY_LABELS_ERROR_MSG = {
+    "default": ("No annotations could be extracted from the input file."
+            "Please check that the input file contains labeled frames."),
+    "dlc": (
+        "Ensure that the paths to the labelled frames are in the "
+        "standard DLC project format: "
+        "labeled-data / <video-name> / "
+        "<filename-with-frame-number>.<extension>"
+        "and that the frames files exist."
+    )
+}
+def annotations_to_coco(
     input_path: Path,
     output_json_path: Path,
+    *,
     coco_image_filenames: str | list[str] | None = None,
     coco_visibility_encoding: str = "ternary",
-) -> dict:
-    """Export input DLC annotations file to COCO format."""
-    # Read annotations as Labels object
-    labels = dlc.load_dlc(input_path, video_search_paths=None)
-
+) -> Path:
+    """Export annotations file to COCO format.
+    
+    Parameters
+    ---------- 
+    input_path : pathlib.Path
+        Path to the input annotations file.
+    output_json_path : pathlib.Path
+        Path to save the output COCO JSON file.
+    coco_image_filenames : str | list[str] | None, optional
+        Optional image filenames to use in the COCO JSON. If provided, 
+        must be a single string (for single-frame videos) or a list of 
+        strings matching the number of labeled frames. If None (default), 
+        generates filenames from video filenames and frame indices.
+    coco_visibility_encoding : str, optional
+        Encoding scheme for keypoint visibility in the COCO JSON file.
+        Options are "ternary" (0: not labeled, 1: labeled but not visible,
+        2: labeled and visible) or "binary" (0: not visible, 1: visible).
+        Default is "ternary".
+    
+    Returns
+    -------
+    pathlib.Path
+        Path to the saved COCO JSON file.
+    
+    Notes
+    -----
+    The format of the input annotations file is automatically inferred based
+    on its extension. See :func:`sleap_io.io.main.load_file` for supported formats.
+    """
+    labels = sio.load_file(input_path)
     # Check if labels object is empty
     if len(labels.labeled_frames) == 0:
-        raise ValueError(
-            "No annotations could be extracted from the input file."
-            "Please check the paths to the labelled frames are in the "
-            "standard DLC project format: "
-            "labeled-data / <video-name> / "
-            "<filename-with-frame-number>.<extension>"
-            "and that the frames files exist."
-        )
-
-    # Export Labels object to COCO
-    coco.write_labels(
+        error_msg = _EMPTY_LABELS_ERROR_MSG["default"]
+        if dlc.is_dlc_file(input_path):
+            error_msg += _EMPTY_LABELS_ERROR_MSG["dlc"]
+        raise ValueError(error_msg)    
+    sio.save_coco(
         labels,
         output_json_path,
-        visibility_encoding=coco_visibility_encoding,
         image_filenames=coco_image_filenames,
+        visibility_encoding=coco_visibility_encoding
     )
-
     return output_json_path