Fix bug

model.py

@@ -147,7 +147,7 @@ class Model:
     
         x_samples_ddim = self.model.decode_first_stage(samples_ddim)
         x_samples_ddim = torch.clamp((x_samples_ddim + 1.0) / 2.0, min=0.0, max=1.0)
-        x_samples_ddim = x_samples_ddim.permute(0, 2, 3, 1).numpy()[0]
+        x_samples_ddim = x_samples_ddim.permute(0, 2, 3, 1).cpu().numpy()[0]
         x_samples_ddim = 255.*x_samples_ddim
         x_samples_ddim = x_samples_ddim.astype(np.uint8)