specify video codec

video-shredder.py

@@ -72,7 +72,7 @@ def processLayout (layout):
       ffmpeg
       .input(inputpath)
       .crop(**item['geomentry'])
-      .output(outputpath)
+      .output(outputpath, pix_fmt='yuv420p')
       .run()
     )
   print('Finished processing all tiles!')