/usr/share/avconv/ is in libav-tools 4:0.8.1-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/avconv/libvpx-1080p.avpreset
/usr/share/avconv/libvpx-1080p50_60.avpreset
/usr/share/avconv/libvpx-360p.avpreset
/usr/share/avconv/libvpx-720p.avpreset
/usr/share/avconv/libvpx-720p50_60.avpreset
/usr/share/avconv/libx264-baseline.avpreset
/usr/share/avconv/libx264-fast.avpreset
/usr/share/avconv/libx264-fast_firstpass.avpreset
/usr/share/avconv/libx264-faster.avpreset
/usr/share/avconv/libx264-faster_firstpass.avpreset
/usr/share/avconv/libx264-ipod320.avpreset
/usr/share/avconv/libx264-ipod640.avpreset
/usr/share/avconv/libx264-lossless_fast.avpreset
/usr/share/avconv/libx264-lossless_max.avpreset
/usr/share/avconv/libx264-lossless_medium.avpreset
/usr/share/avconv/libx264-lossless_slow.avpreset
/usr/share/avconv/libx264-lossless_slower.avpreset
/usr/share/avconv/libx264-lossless_ultrafast.avpreset
/usr/share/avconv/libx264-main.avpreset
/usr/share/avconv/libx264-medium.avpreset
/usr/share/avconv/libx264-medium_firstpass.avpreset
/usr/share/avconv/libx264-placebo.avpreset
/usr/share/avconv/libx264-placebo_firstpass.avpreset
/usr/share/avconv/libx264-slow.avpreset
/usr/share/avconv/libx264-slow_firstpass.avpreset
/usr/share/avconv/libx264-slower.avpreset
/usr/share/avconv/libx264-slower_firstpass.avpreset
/usr/share/avconv/libx264-superfast.avpreset
/usr/share/avconv/libx264-superfast_firstpass.avpreset
/usr/share/avconv/libx264-ultrafast.avpreset
/usr/share/avconv/libx264-ultrafast_firstpass.avpreset
/usr/share/avconv/libx264-veryfast.avpreset
/usr/share/avconv/libx264-veryfast_firstpass.avpreset
/usr/share/avconv/libx264-veryslow.avpreset
/usr/share/avconv/libx264-veryslow_firstpass.avpreset