我的操作系统：Linux Mint 17.1 (x64) + Cinnamon
我试图让我的 Linux 播放 wma 文件，但我破坏了一些东西，因为我现在无法播放任何视频。我尝试过的：
- 删除
~/.gstreamer-1.0文件夹 - 正在运行
sudo /usr/share/doc/libdvdread4/install-css.sh（也许这破坏了我的系统？） - 尝试通过 apt-get 安装一些库（例如名称中包含 libavcodec 的库，也可能是其他库）
现在，当我尝试运行 mplayer 时，出现错误：
> mplayer
mplayer: error while loading shared libraries: libavcodec.so.54: cannot open shared object file: No such file or directory
其他播放器（vlc）也不起作用。所以我尝试更新我的系统。sudo apt-get update抛出一些错误：
(...)
Err http://ppa.launchpad.net trusty/main Sources
404 Not Found
Get:21 http://packages.linuxmint.com rebecca/upstream i386 Packages [30,0 kB]
Err http://ppa.launchpad.net trusty/main amd64 Packages
404 Not Found
Hit http://archive.ubuntu.com trusty-updates/restricted Translation-en
Err http://ppa.launchpad.net trusty/main i386 Packages
404 Not Found
(...)
W: Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/dists/trusty/main/source/Sources 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/dists/trusty/main/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/dists/trusty/main/binary-i386/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
sudo apt-get upgrade根本没用：
Reading package lists...
Building dependency tree...
Reading state information...
You might want to run 'apt-get -f install' to correct these.
The following packages have unmet dependencies:
audacity : Depends: libavcodec54 (>= 6:9.1-1) but it is not installed or
libavcodec-extra-54 (>= 6:9.13) but it is not installed
ffmpeg : Depends: libavcodec54 (>= 7:1.2.5~) but it is not installed or
libavcodec-extra-54 (>= 7:1.2.5~) but it is not installed
gstreamer1.0-libav : Depends: libavcodec54 (>= 6:9.1-1) but it is not installed or
libavcodec-extra-54 (>= 6:9.13) but it is not installed
libavdevice53 : Depends: libavcodec54 (>= 7:1.2.5~) but it is not installed or
libavcodec-extra-54 (>= 7:1.2.5~) but it is not installed
libavfilter3 : Depends: libavcodec54 (>= 7:1.2.5~) but it is not installed or
libavcodec-extra-54 (>= 7:1.2.5~) but it is not installed
libavformat54 : Depends: libavcodec54 (>= 7:1.2.5~) but it is not installed or
libavcodec-extra-54 (>= 7:1.2.5~) but it is not installed
libchromaprint0 : Depends: libavcodec54 (>= 6:9.1-1) but it is not installed or
libavcodec-extra-54 (>= 6:9.10) but it is not installed
libopencv-highgui2.4 : Depends: libavcodec54 (>= 6:9.1-1) but it is not installed or
libavcodec-extra-54 (>= 6:9.10) but it is not installed
mencoder : Depends: libavcodec54 (>= 6:9.1-1) but it is not installed or
libavcodec-extra-54 (>= 6:9.11) but it is not installed
mplayer : Depends: libavcodec54 (>= 6:9.1-1) but it is not installed or
libavcodec-extra-54 (>= 6:9.11) but it is not installed
vlc-nox : Depends: libavcodec54 (>= 6:9.1-1) but it is not installed or
libavcodec-extra-54 (>= 6:9.18) but it is not installed
E: Unmet dependencies. Try using -f.
然后我尝试了sudo apt-get -f install：
Reading package lists... Done
Building dependency tree
Reading state information... Done
Correcting dependencies... Done
The following packages were automatically installed and are no longer required:
folder-color-switcher gir1.2-nemo-3.0 nemo-emblems
nemo-folder-color-switcher python-nemo python-psutil
Use 'apt-get autoremove' to remove them.
The following extra packages will be installed:
libavcodec54
The following NEW packages will be installed:
libavcodec54
0 upgraded, 1 newly installed, 0 to remove and 13 not upgraded.
Need to get 2715 kB of archives.
After this operation, 7309 kB of additional disk space will be used.
Do you want to continue? [Y/n] Y
WARNING: The following packages cannot be authenticated!
libavcodec54
Install these packages without verification? [y/N] y
Err http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/ trusty/main libavcodec54 amd64 7:1.2.6-1~trusty1
404 Not Found
E: Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/pool/main/f/ffmpeg/libavcodec54_1.2.6-1~trusty1_amd64.deb 404 Not Found
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
然后我运行sudo apt-get update --fix-missing，这给了我类似的错误sudo apt-get update。
我还尝试了 synaptic 包管理器，它在启动时显示“您的系统上有 11 个损坏的包！...”。我尝试了一下Edit => Fix Broken Packages，似乎什么也没做（甚至没有抛出错误）。然后我选择了“损坏的依赖项过滤器”，标记了所有要重新安装的软件包，在几个屏幕之后我收到了错误：
W: Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/pool/main/f/ffmpeg/libavcodec54_1.2.6-1~trusty1_amd64.deb
404 Not Found
W: Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/pool/main/f/ffmpeg/ffmpeg_1.2.6-1~trusty1_amd64.deb
404 Not Found
W: Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/pool/main/f/ffmpeg/libavdevice53_1.2.6-1~trusty1_amd64.deb
404 Not Found
W: Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/pool/main/f/ffmpeg/libavfilter3_1.2.6-1~trusty1_amd64.deb
404 Not Found
W: Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/pool/main/f/ffmpeg/libavformat54_1.2.6-1~trusty1_amd64.deb
404 Not Found
所以有人知道我破坏了什么/如何破坏以及如何修复它？谢谢。
答案1
我是这样修复的：
- 打开“软件源”
- 在 PPA 选项卡中搜索名称中带有“ffmpeg”的条目并将其全部删除
然后在终端中运行这些命令（它们更新/清理整个系统。如果您不想升级发行版，您可以省略带有
dist-upgrade部分的行）：sudo apt-get -f install sudo apt-get update sudo apt-get upgrade # sudo apt-get dist-upgrade sudo apt-get autoremove sudo apt-get autoclean sudo apt-get clean可以选择安装 mplayer 和/或 vlc 来播放视频/音频文件：
sudo apt-get install mplayer sudo apt-get install vlc
一切又恢复正常了。
答案2
更容易（如果你有 Synaptic）
- 打开终端并运行
sudo synaptic - 在 Synaptic 中导航至“设置”>“存储库”
找到给您带来错误的存储库。
在这里您可以“禁用”或选择并删除。 当您完成存储库后，请务必按“确定”，让 Synaptic 发挥作用。
退出 Synaptic 并确认
按“ctrl + Q”并确保您退出 Synaptic而不仅仅是最小化它，否则 apt-get 将返回使用错误。
- 打开终端并运行
sudo apt-get update
就这样，没有更多错误了:)
希望这是可以理解的，到目前为止只使用 Linux 一周。