use cpu

app.py

@@ -85,7 +85,7 @@ def inference(model_name, prompt, guidance, steps, width=512, height=512, seed=0
       current_model = model
       model_path = current_model.path
 
-  generator = torch.Generator('cuda').manual_seed(seed) if seed != 0 else None
+  generator = torch.Generator('cuda' if torch.cuda.is_available() else 'cpu').manual_seed(seed) if seed != 0 else None
 
   if img is not None:
     return img_to_img(model_path, prompt, neg_prompt, img, strength, guidance, steps, width, height, generator)