diff --git a/gnes/preprocessor/__init__.py b/gnes/preprocessor/__init__.py
index de83a821..ccae1ae2 100644
--- a/gnes/preprocessor/__init__.py
+++ b/gnes/preprocessor/__init__.py
@@ -33,12 +33,12 @@
     'FFmpegVideoSegmentor': 'video.ffmpeg',
     'ShotDetectPreprocessor': 'video.shotdetect',
     'VideoEncoderPreprocessor': 'video.video_encoder',
+    'VideoDecoderPreprocessor': 'video.video_decoder',
     'AudioVanilla': 'audio.audio_vanilla',
     'BaseAudioPreprocessor': 'base',
     'RawChunkPreprocessor': 'base',
     'GifChunkPreprocessor': 'video.ffmpeg',
     'VggishPreprocessor': 'audio.vggish_example',
-    'VideoDecodePreprocessor': 'video.video_decode',
     'FrameSelectPreprocessor': 'video.frame_select'
 }
 
diff --git a/gnes/preprocessor/io_utils/ffmpeg.py b/gnes/preprocessor/io_utils/ffmpeg.py
index 311253c9..3fb9a653 100644
--- a/gnes/preprocessor/io_utils/ffmpeg.py
+++ b/gnes/preprocessor/io_utils/ffmpeg.py
@@ -85,7 +85,7 @@ def compile_args(input_fn: str = 'pipe:',
     """Wrapper for various `FFmpeg <https://www.ffmpeg.org/>`_ related applications (ffmpeg,
     ffprobe).
     """
-    args = ['ffmpeg', '-threads', '0']
+    args = ['ffmpeg', '-threads', '1']
 
     input_args = []
     fmt = input_options.pop('format', None)
diff --git a/gnes/preprocessor/io_utils/gif.py b/gnes/preprocessor/io_utils/gif.py
index 4e740ec8..24899db6 100644
--- a/gnes/preprocessor/io_utils/gif.py
+++ b/gnes/preprocessor/io_utils/gif.py
@@ -58,8 +58,8 @@ def capture_frames(input_fn: str = 'pipe:',
         if pix_fmt == 'rgba':
             depth = 4
 
-        frames = np.frombuffer(out,
-                               np.uint8).reshape([-1, height, width, depth])
+        frames = np.frombuffer(out, np.uint8).copy()
+        frames = frames.reshape([-1, height, width, depth])
         return frames
 
 
diff --git a/gnes/preprocessor/io_utils/video.py b/gnes/preprocessor/io_utils/video.py
index 7ace4b6a..6f71e866 100644
--- a/gnes/preprocessor/io_utils/video.py
+++ b/gnes/preprocessor/io_utils/video.py
@@ -219,8 +219,8 @@ def capture_frames(input_fn: str = 'pipe:',
         if pix_fmt == 'rgba':
             depth = 4
 
-        frames = np.frombuffer(out,
-                               np.uint8).reshape([-1, height, width, depth])
+        frames = np.frombuffer(out, np.uint8).copy()
+        frames = frames.reshape([-1, height, width, depth])
         return frames
 
 
diff --git a/gnes/preprocessor/video/video_decode.py b/gnes/preprocessor/video/video_decoder.py
similarity index 98%
rename from gnes/preprocessor/video/video_decode.py
rename to gnes/preprocessor/video/video_decoder.py
index 7c3432f1..e20a8a60 100644
--- a/gnes/preprocessor/video/video_decode.py
+++ b/gnes/preprocessor/video/video_decoder.py
@@ -19,7 +19,7 @@
 from ..io_utils import video as video_util
 
 
-class VideoDecodePreprocessor(BaseVideoPreprocessor):
+class VideoDecoderPreprocessor(BaseVideoPreprocessor):
     store_args_kwargs = True
 
     def __init__(self,
diff --git a/gnes/proto/__init__.py b/gnes/proto/__init__.py
index 47f91380..6f531846 100644
--- a/gnes/proto/__init__.py
+++ b/gnes/proto/__init__.py
@@ -91,7 +91,8 @@ def blob2array(blob: 'gnes_pb2.NdArray') -> np.ndarray:
     """
     Convert a blob proto to an array.
     """
-    return np.frombuffer(blob.data, dtype=blob.dtype).reshape(blob.shape)
+    x = np.frombuffer(blob.data, dtype=blob.dtype).copy()
+    return x.reshape(blob.shape)
 
 
 def array2blob(x: np.ndarray) -> 'gnes_pb2.NdArray':
diff --git a/tests/yaml/preprocessor-video_decode.yml b/tests/yaml/preprocessor-video_decode.yml
index c8e36f75..58a9c72c 100644
--- a/tests/yaml/preprocessor-video_decode.yml
+++ b/tests/yaml/preprocessor-video_decode.yml
@@ -1,4 +1,4 @@
-!VideoDecodePreprocessor
+!VideoDecoderPreprocessor
 parameters:
   frame_rate: 5
   vframes: 1