sudo apt-get install gstreamer1.0/xenial-proposed

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Note, selecting 'gstreamer1.0-plugins-ugly-amr' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-videosink' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-alsa' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-ugly-dbg' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-ugly-doc' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-base-apps' for regex 'gstreamer1.0'
Note, selecting 'libgstreamer1.0-dev' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-hybris:i386' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-tools' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-good' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-qapt' for regex 'gstreamer1.0'
Note, selecting 'libgstreamer1.0-0-dbg' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-espeak' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-nice' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-videosource' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-crystalhd' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-fluendo-mp3' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-bad' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-base' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-audiosource' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-bad-videoparsers' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-really-bad' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-clutter' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-pulseaudio' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-pocketsphinx' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-bad-dbg' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-bad-doc' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-visualization' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-bad-faad' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-lame' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-x' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-vaapi-doc' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-libav' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-base-dbg' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-good-dbg' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-base-doc' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-good-doc' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-dvswitch' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-clutter-3.0' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-vaapi' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-libav-dbg' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-packagekit' for regex 'gstreamer1.0'
Note, selecting 'libgstreamer1.0-0' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-ffmpeg' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-plugins-ugly' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-doc' for regex 'gstreamer1.0'
Note, selecting 'gstreamer1.0-audiosink' for regex 'gstreamer1.0'
E: Release 'xenial-proposed' for 'gstreamer1.0-audiosink' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-audiosource' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-clutter-3.0' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-videosource' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-videosink' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-visualization' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-ffmpeg' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-qapt' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-clutter' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-crystalhd' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-dvswitch' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-espeak' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-fluendo-mp3' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-nice' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-packagekit' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-pocketsphinx' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-vaapi' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-vaapi-doc' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-lame' was not found
E: Release 'xenial-proposed' for 'gstreamer1.0-plugins-really-bad' was not found