/usr/lib/x86_64-linux-gnu/ is in libqtgstreamer-dev 1.2.0-4.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/x86_64-linux-gnu/cmake/
/usr/lib/x86_64-linux-gnu/cmake/QtGStreamer/
/usr/lib/x86_64-linux-gnu/cmake/QtGStreamer/QtGStreamerConfig.cmake
/usr/lib/x86_64-linux-gnu/cmake/QtGStreamer/QtGStreamerConfigCommon.cmake
/usr/lib/x86_64-linux-gnu/cmake/QtGStreamer/QtGStreamerConfigVersion.cmake
/usr/lib/x86_64-linux-gnu/cmake/QtGStreamer/QtGStreamerTargets-relwithdebinfo.cmake
/usr/lib/x86_64-linux-gnu/cmake/QtGStreamer/QtGStreamerTargets.cmake
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/QtGLib-2.0.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/QtGStreamer-1.0.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/QtGStreamerUi-1.0.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/QtGStreamerUtils-1.0.pc
/usr/lib/x86_64-linux-gnu/libQtGLib-2.0.so
/usr/lib/x86_64-linux-gnu/libQtGStreamer-1.0.so
/usr/lib/x86_64-linux-gnu/libQtGStreamerUi-1.0.so
/usr/lib/x86_64-linux-gnu/libQtGStreamerUtils-1.0.so