add background class

Author: probicheaux

roboflow/util/model_processor.py

@@ -279,6 +279,7 @@ def _process_rfdetr(model_type: str, model_path: str, filename: str) -> str:
 def get_classnames_txt_for_rfdetr(model_path: str, pt_file: str):
     class_names_path = os.path.join(model_path, "class_names.txt")
     if os.path.exists(class_names_path):
+        maybe_prepend_dummy_class(class_names_path)
         return class_names_path
 
     import torch
@@ -289,6 +290,7 @@ def get_classnames_txt_for_rfdetr(model_path: str, pt_file: str):
         with open(class_names_path, "w") as f:
             for class_name in args["class_names"]:
                 f.write(class_name + "\n")
+        maybe_prepend_dummy_class(class_names_path)
         return class_names_path
 
     raise FileNotFoundError(
@@ -298,6 +300,16 @@ def get_classnames_txt_for_rfdetr(model_path: str, pt_file: str):
         f"please create a class_names.txt file in the model path with the class names in new lines in the order of the classes in the model.\n"
     )
 
+def maybe_prepend_dummy_class(class_name_file: str):
+    with open(class_name_file, "r") as f:
+        class_names = f.readlines()
+
+    dummy_class = "background_class83422\n"
+    if dummy_class not in class_names:
+        class_names.insert(0, dummy_class)
+        with open(class_name_file, "w") as f:
+            f.writelines(class_names)
+
 
 def _process_huggingface(
     model_type: str, model_path: str, filename: str = "fine-tuned-paligemma-3b-pt-224.f16.npz"