我最近升级到了 Ubuntu 18.04，DVD 播放器停止工作了。经过一番研究，我尝试重新安装 gstreamer，但遇到了一个似乎与 Ubuntu 18.04 有关的问题，这超出了我的理解范围。以下是该命令的输出：
$ sudo apt-get install gstreamer1.0-tools gstreamer1.0-alsa gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-libav
Reading package lists... Done
Building dependency tree
Reading state information... Done
gstreamer1.0-plugins-base is already the newest version (1.14.1-1ubuntu1~ubuntu18.04.1).
gstreamer1.0-plugins-base set to manually installed.
gstreamer1.0-libav is already the newest version (1.14.1-1~ubuntu18.04.1).
gstreamer1.0-tools is already the newest version (1.14.1-1~ubuntu18.04.1).
gstreamer1.0-tools set to manually installed.
gstreamer1.0-plugins-ugly is already the newest version (1.14.1-1~ubuntu18.04.1).
gstreamer1.0-plugins-good is already the newest version (1.14.1-1ubuntu1~ubuntu18.04.1).
gstreamer1.0-plugins-good set to manually installed.
gstreamer1.0-alsa is already the newest version (1.14.1-1ubuntu1~ubuntu18.04.1).
gstreamer1.0-alsa set to manually installed.
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
gstreamer1.0-plugins-bad : Depends: libgstreamer-plugins-bad1.0-0 (= 1.14.0-1ubuntu1) but 1.14.1-1ubuntu1~ubuntu18.04.1 is to be installed
E: Unable to correct problems, you have held broken packages.
非常感谢任何帮助（特别是孩子们:)）
答案1
我也遇到了一些困难，但我找到了一个可以解决问题的 .deb 包：
从https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/3267-deletedppa/+build/14926540 下载
gstreamer1.0-插件-bad_1.14.1-1ubuntu1~ubuntu18.04.1_amd64.deb
并安装它。