using regex instead of split

Signed-off-by: man13 <man13@inf.ufpr.br>

lib/thumbnail/strategies/video_thumbnail_generator.rb

 require 'streamio-ffmpeg'
-require 'mimemagic'
 
 module Thumbnail
   module Strategies
@@ -22,7 +21,7 @@ module Thumbnail
       end
 
       def can_generate?(media)
-        MimeMagic.by_magic(media).type.split('/').first == 'video'
+        MimeMagic.by_magic(media).type =~ /video/
       end
       private