userdata/playercorefactory.xml

<playercorefactory>
  <players>
    <player name="Photo-Reframe" type="ExternalPlayer" audio="false" video="true">
      <filename>/home/kodi/.kodi/bin/run-script.py</filename>
      <args>--play --fullscreen --read-only "{0}"</args>
      <hidexbmc>true</hidexbmc>
      <hideconsole>false</hideconsole>
      <warpcursor>none</warpcursor>
    </player>
  </players>
  <rules action="prepend">
    <rule filetypes="m3u" filename="playlist.*" player="Photo-Reframe"/>
  </rules>
</playercorefactory>

WARNING <general>: CPlayerCoreFactory::GetPlayer(Photo-Reframe): no such player: Photo-Reframe