diff --git a/ovgenpy/ovgenpy.py b/ovgenpy/ovgenpy.py
index 7cf87c4..205a76f 100644
--- a/ovgenpy/ovgenpy.py
+++ b/ovgenpy/ovgenpy.py
@@ -142,7 +142,8 @@ class Ovgen:
             renderer.render_frame(datas)
 
             # Output frame
-            frame = renderer.get_frame()
+            if self.outputs:
+                frame = renderer.get_frame()
             for output in self.outputs:
                 output.write_frame(frame)
 
diff --git a/ovgenpy/renderer.py b/ovgenpy/renderer.py
index 33c63d7..5ec537f 100644
--- a/ovgenpy/renderer.py
+++ b/ovgenpy/renderer.py
@@ -1,16 +1,13 @@
 from typing import Optional, List, Tuple, TYPE_CHECKING
 
-import matplotlib
 import numpy as np
 from dataclasses import dataclass
+from matplotlib import pyplot as plt
+from matplotlib.backends.backend_agg import FigureCanvasAgg
 
 from ovgenpy.outputs import RGB_DEPTH
 from ovgenpy.util import ceildiv
 
-matplotlib.use('agg')
-from matplotlib import pyplot as plt
-from matplotlib.backends.backend_agg import FigureCanvasAgg
-
 if TYPE_CHECKING:
     from matplotlib.axes import Axes
     from matplotlib.figure import Figure