From 71cb36f948dc1c0eace14c0e056b3e5e90a76cf8 Mon Sep 17 00:00:00 2001
From: felix <madwang@tencent.com>
Date: Fri, 23 Aug 2019 14:50:24 +0800
Subject: [PATCH] minor fix

---
 gnes/preprocessor/io_utils/video.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/gnes/preprocessor/io_utils/video.py b/gnes/preprocessor/io_utils/video.py
index ef54a9e3..21238dea 100644
--- a/gnes/preprocessor/io_utils/video.py
+++ b/gnes/preprocessor/io_utils/video.py
@@ -54,10 +54,12 @@ def scale_video(input_filename: str = 'pipe:',
         'vcodec': vcodec,
         'pix_fmt': pix_fmt,
         'crf': crf,
-        's': scale,
         'framerate': frame_rate
     }
 
+    if scale:
+        out_kwargs['s'] = scale
+
     if capture_stdout:
         out_kwargs['format'] = format
         # an empty moov means it doesn't need to seek and thus works with a pipe.