Update app.py

app.py

@@ -105,6 +105,7 @@ class ModelManager:
     def __init__(self):
         self._inspy: Optional[Remover] = None
         self._withoutbg: Optional[object] = None
+        self._withoutbg_had_gpu: bool = False  # Track if withoutBG was loaded with GPU
         self._torch_models: Dict[str, torch.nn.Module] = {}
         self._torch_model_on_gpu: Optional[str] = None
         self._rembg_sessions: Dict[str, object] = {}
@@ -130,9 +131,24 @@ class ModelManager:
             self._inspy = Remover(jit=False)
         return self._inspy
 
-    def _load_withoutbg(self):
-        if self._withoutbg is None:
+    def _load_withoutbg(self, force_reload: bool = False):
+        """
+        Load withoutBG model. 
+        Automatically reloads if GPU became available after initial load.
+        """
+        gpu_available_now = torch.cuda.is_available()
+        
+        # Reload if: forced, not loaded yet, or GPU is now available but wasn't before
+        need_reload = (
+            force_reload or 
+            self._withoutbg is None or 
+            (gpu_available_now and not self._withoutbg_had_gpu)
+        )
+        
+        if need_reload:
             self._withoutbg = WithoutBG.opensource()
+            self._withoutbg_had_gpu = gpu_available_now
+        
         return self._withoutbg
 
     def _offload_torch_models_from_gpu(self, keep_name: str):
@@ -274,6 +290,7 @@ class ModelManager:
             out = ensure_rgba(out)
 
         elif model_name == "withoutBG":
+            # Will auto-reload if GPU became available (ZeroGPU)
             model = self._load_withoutbg()
             out = model.remove_background(img_rgb)
             out = ensure_rgba(out)