/usr/include/ is in libplayercore3.0-dev 3.0.2+dfsg-3ubuntu2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/player-3.0/
/usr/include/player-3.0/libplayercore/
/usr/include/player-3.0/libplayercore/plugins.h
/usr/include/player-3.0/libplayercore/playercore.h
/usr/include/player-3.0/libplayercore/devicetable.h
/usr/include/player-3.0/libplayercore/wallclocktime.h
/usr/include/player-3.0/libplayercore/property.h
/usr/include/player-3.0/libplayercore/globals.h
/usr/include/player-3.0/libplayercore/filewatcher.h
/usr/include/player-3.0/libplayercore/configfile.h
/usr/include/player-3.0/libplayercore/device.h
/usr/include/player-3.0/libplayercore/drivertable.h
/usr/include/player-3.0/libplayercore/driver.h
/usr/include/player-3.0/libplayercore/playertime.h
/usr/include/player-3.0/libplayercore/message.h