Use Engine enum and validate model path

Switch DLCProcessorSettings.model_type default from a raw string to the Engine enum (Engine.PYTORCH) and change DLCLiveProcessor.get_model_backend to return an Engine instead of a string for stronger typing. Update the GUI to validate empty model path input, reuse the resolved model backend (model_bknd) when building settings, improve the backend-detection error message, and allow selecting any file/directory in the model file dialog (adjusted name filter label for TensorFlow model directories). Also fix a relative import in dlclivegui.temp.__init__.py. Note: this changes the get_model_backend return type (callers expecting a string must use .value if needed).

Author: C-Achard

dlclivegui/config.py

@@ -241,7 +241,7 @@ class DLCProcessorSettings(BaseModel):
     resize: float = Field(default=1.0, gt=0)
     precision: Precision = "FP32"
     additional_options: dict[str, Any] = Field(default_factory=dict)
-    model_type: Engine = "pytorch"
+    model_type: Engine = Engine.PYTORCH
     single_animal: bool = True
 
     @field_validator("dynamic", mode="before")

dlclivegui/gui/main_window.py

@@ -876,11 +876,13 @@ def _parse_json(self, value: str) -> dict:
 
     def _dlc_settings_from_ui(self) -> DLCProcessorSettings:
         model_path = self.model_path_edit.text().strip()
+        if model_path == "":
+            raise ValueError("Model path cannot be empty. Please enter a valid path to a DLCLive model file.")
         try:
-            DLCLiveProcessor.get_model_backend(model_path)
+            model_bknd = DLCLiveProcessor.get_model_backend(model_path)
         except Exception as e:
             raise RuntimeError(
-                "Could not determine model backend from path."
+                "Could not determine model backend from path. "
                 "Please ensure the model file is valid and has an appropriate extension "
                 "(.pt, .pth for PyTorch or model directory for TensorFlow)."
             ) from e
@@ -891,7 +893,7 @@ def _dlc_settings_from_ui(self) -> DLCProcessorSettings:
             dynamic=self._config.dlc.dynamic,  # Preserve from config
             resize=self._config.dlc.resize,  # Preserve from config
             precision=self._config.dlc.precision,  # Preserve from config
-            model_type=DLCLiveProcessor.get_model_backend(model_path),
+            model_type=model_bknd,
             # additional_options=self._parse_json(self.additional_options_edit.toPlainText()),
         )
 
@@ -974,13 +976,13 @@ def _action_browse_model(self) -> None:
         preselect = self._model_path_store.suggest_selected_file()
 
         dlg = QFileDialog(self, "Select DLCLive model file")
-        dlg.setFileMode(QFileDialog.FileMode.ExistingFile)
+        dlg.setFileMode(QFileDialog.FileMode.AnyFile)
         dlg.setNameFilters(
             [
                 "Model files (*.pt *.pth)",
                 "PyTorch models (*.pt *.pth)",
                 # "TensorFlow models (*.pb)",
-                "All files (*.*)",
+                "TensorFlow model directory (*.*)",
             ]
         )
         dlg.setDirectory(start_dir)

dlclivegui/services/dlc_processor.py

@@ -100,8 +100,8 @@ def __init__(self) -> None:
         self._processor_overhead_times: deque[float] = deque(maxlen=60)
 
     @staticmethod
-    def get_model_backend(model_path: str) -> str:
-        return Engine.from_model_path(model_path).value
+    def get_model_backend(model_path: str) -> Engine:
+        return Engine.from_model_path(model_path)
 
     def configure(self, settings: DLCProcessorSettings, processor: Any | None = None) -> None:
         self._settings = settings

dlclivegui/temp/__init__.py

@@ -1,3 +1,3 @@
-from engine import Engine  # type: ignore
+from .engine import Engine  # type: ignore
 
 __all__ = ["Engine"]