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Translating by Yinr
Multimedia Apps for the Linux Console Linux 终端下的多媒体应用
The Linux console supports multimedia, so you can enjoy music, movies, photos, and even read PDF files.
Linux 终端是支持多媒体的，所以你可以在终端听音乐，看电影，看图片，甚至是阅读 PDF。
When last we met, we learned that the Linux console supports multimedia. Yes, really! You can enjoy music, movies, photos, and even read PDF files without being in an X session with MPlayer, fbi, and fbgs. And, as a bonus, you can enjoy a Matrix-style screensaver for the console, CMatrix. 在我们上次见面时（？），我们了解到 Linux 终端可以支持多媒体。是的，这是真的！你可以使用 Mplayer、fbi 和 fbgs 来实现不打开 X 进程就听音乐、看电影、看照片，甚至阅读 PDF。此外，你还可以通过 CMatrix 来体验黑客帝国（Matrix）风格的屏幕保护。
You will probably have make some tweaks to your system to make this work. The examples used here are for Ubuntu Linux 16.04. 不过你可能需要对系统进行一些修改才能达到前面这些目的。以下的操作都是在 Ubuntu 16.04 上演示的。
MPlayer
You're probably familiar with the amazing and versatile MPlayer, which supports almost every video and audio format, and runs on nearly everything, including Linux, Android, Windows, Mac, Kindle, OS/2, and AmigaOS. Using MPLayer in your console will probably require some tweaking, depending on your Linux distribution. To start, try playing a video: 你可能会比较熟悉功能丰富的 MPlayer。它支持几乎所有的视频与音频格式，并且能在绝大部分现有平台上运行，像 Linux，Android，Windows，Mac，Kindle，OS/2 甚至是 AmigaOS。不过要在你的终端运行 MPlayer 可能需要多做一点工作，这些工作与你使用的 Linux 发行版有关。来，我们试着播放一个视频：
$ mplayer [视频文件名]
If it works, then hurrah, and you can invest your time in learning useful MPlayer options, such as controlling the size of the video screen. However, some Linux distributions are managing the framebuffer differently than in the olden days, and you may have to adjust some settings to make it work. This is how to make it work on recent Ubuntu releases. 如果上面的命令正常执行了，那么很好，接下来你可以把时间放在了解 MPlayer 的常用选项上了，譬如设定视频大小等。但是，有些 Linux 发行版在对帧缓冲（framebuffer）的处理方式上可能会与早期的不同，那么你就需要进行一些设置才能让其正常工作了。下面是在最近的 Ubuntu 发行版上需要做的一些操作。
First, add yourself to the video group. 首先，将你添加到 video 用户组。
Second, verify that /etc/modprobe.d/blacklist-framebuffer.conf has this line: #blacklist vesafb. It should already be commented out, and if it isn't then comment it. All the other module lines should be un-commented, which prevents them from loading. Side note: if you want to dig more deeply into managing your framebuffer, the module for your video card may give better performance.
其次，确认 /etc/modprobe.d/blacklist-framebuffer.conf 文件中包含这样一行：#blacklist vesafb。这一行应该默认被注释掉了，如果不是的话，那就手动把它注释掉。此外的其他模块行需要确认没有被注释，这样设置才能保证那些模块不会被载入。注：如果你想要对控制帧缓冲（framebuffer）有更深入的了解，针对你的显卡的这些模块将给你提供更深入的认识。
Add these two modules to the end of /etc/initramfs-tools/modules, vesafb and fbcon, then rebuild the initramfs image:
在 /etc/initramfs-tools/modules 的结尾增加两个模块：vesafb 和 fbcon，然后更新 iniramfs 镜像：
$ sudo nano /etc/initramfs-tools/modules
# List of modules that you want to include in your initramfs.
# They will be loaded at boot time in the order below.
fbcon
vesafb
$ sudo update-initramfs -u
fbcon is the Linux framebuffer console. It runs on top of the framebuffer and adds graphical features. It requires a framebuffer device, which is supplied by the vesafb module.
fbcon 是 Linux 帧缓冲（framebuffer）终端，它运行在帧缓冲（framebuffer）之上并为其增加图形功能。fbcon 需要一个帧缓冲（framebuffer）设备，这则是由 vesafb 模块来提供的。
Now you must edit your GRUB2 configuration. In /etc/default/grub you should see a line like this:
接下来，你需要修改你的 GRUB2 配置。在 /etc/default/grub 中你将会看到类似下面的一行：
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
It may have some other options, but it should be there. Add vga=789:
它也可能还会有一些别的参数，不用管它，在其后加上 vga=789：
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash vga=789"
Reboot and enter your console (Ctrl+Alt+F1), and try playing a video. This command selects the fbdev2 video device; I haven't learned yet how to know which one to use, but I had to use it to play the video. The default screen size is 320x240, so I scaled it to 960:
重启之后进入你的终端（Ctrl+Alt+F1）（LCTT 译注：在某些发行版中 Ctrl+Alt+F1 默认为图形界面，可以尝试 Ctrl+Alt+F2），然后就可以尝试播放一个视频了。下面的命令指定了 fbdev2 为视频输出设备，虽然我还没弄明白如何去选择用哪个输入设备，但是我用它成功过。默认的视频大小是 320x240，在此我给缩放到了 960：
$ mplayer -vo fbdev2 -vf scale -zoom -xy 960 AlienSong_mp4.mov
And behold Figure 1. It's grainy because I have a low-fi copy of this video, not because MPlayer is making it grainy. 来看图 1。粗糙的画面是由于我原视频的质量不高，而不是 MPlayer 的显示问题。
MPLayer plays CDs, DVDs, network streams, and has a giant batch of playback options, which I shall leave as your homework to explore. MPlayer 可以播放 CD、DVD 以及网络视频流，并且还有一系列的回放选项，这些将作为作业让大家自己去发现。
fbi Image Viewer
fbi 图片查看器
fbi, the framebuffer image viewer, comes in the fbida package on most Linuxes. It has native support for the common image file formats, and uses convert (from Image Magick), if it is installed, for other formats. Its simplest use is to view a single image file:
fbi 是一个帧缓冲图片查看器。在大部分的 Linux 发行版中都，它被包含在 fbida 包中。它原生支持一些常见的图片格式，而如果你安装了 convert（来自于 Image Magick），那么它还能借此打开一些其他格式。最简单的用法是用来查看一个图片文件：
$ fbi 文件名
Use the arrow keys to scroll a large image, + and - to zoom, and r and l to rotate 90 degress right and left. Press the Escape key to close the image. You can play a slideshow by giving fbi a list of files:
你可以使用方向键来在大图片中移动视野，使用 + 和 - 来缩放，或者使用 r 或 l 来向右或向左旋转 90 度。Escape 键则可以关闭查看的图片。此外，你还可以给 fbi 一个文件列表来实现幻灯播放：
$ fbi --list 文件列表.txt
fbi supports autozoom. With -a fbi controls the zoom factor. --autoup and --autodown tell fbi to only zoom up or down. Control the blend time between images with --blend [time], in milliseconds. Press the k and j keys to jump behind and ahead in your file list.
fbi 还支持自动缩放。还可以使用 -a 选项来控制缩放比例。--autoup 和 --autodown 则是用于告知 fbi 只进行放大或者缩小。要调整图片切换时淡入淡出的时间则可以使用 --blend [时间] 来指定一个毫秒为单位的时间长度。使用 k 和 j 键则可以切换文件列表中的上一张或下一张图片。
fbi has commands for creating file lists from images you have viewed, and for exporting your commands to a file, and a host of other cool options. Check out man fbi for complete options.
fbi 还提供了命令来为你浏览过的文件创建文件列表，或者将你的命令导出到文件中，以及一系列其它很棒的选项。你可以通过查看 man fbi 来查阅完整的选项列表。
CMatrix Console Screensaver
CMatrix 终端屏保
The Matrix screensaver is still my favorite (Figure 2), second only to the bouncing cow. CMatrix runs on the console. Simply type cmatrix to start it, and Ctrl+C stops it. Run cmatrix -s to launch it in screensaver mode, which exits on any keypress. -C changes the color. Your choices are green, red, blue, yellow, white, magenta, cyan, and black.
黑客帝国（The Matrix）屏保仍然是我非常喜欢的屏保（图 2），仅次于弹跳牛（bouncing cow）。CMatrix 可以在终端运行。要运行它只需输入 cmatrix，然后可以用 Ctrl+C 来停止运行。执行 cmatrix -s 则启动屏保模式，这样的话按任意键都能退出屏保。-C 参数可以设定颜色，譬如绿色（green）、红色（red）、蓝色（blue）、黄色（yellow）、白色（white）、紫色（magenta）、青色（cyan）或者黑色（black）。
CMatrix supports asynchronous key presses, which means you can change options while it's running. CMatrix 还支持异步按键，这意味着你可以在它运行的时候改变设置选项。
-B is all bold text, and -B is partially bold.
-B 设置全部使用粗体，而 -b（LCTT 译注：原文误为 -B）则可以设置部分字体加粗。
fbgs PDF Viewer
fbgs PDF 阅读器
It seems that the addiction to PDF documents is pandemic and incurable, though PDFs are better than they used to be, with live hyperlinks, copy-paste, and good text search. The fbgs console PDF viewer is part of the fbida package. Options include page size, resolution, page selections, and most fbi options, with the exceptions listed in man fbgs. The main option I use is page size; you get -l, xl, and xxl to choose from:
看起来，对 PDF 文档的上瘾是普遍而无法阻止的，尽管 PDF 比它之前好了很多，譬如实时超链接、复制粘贴以及更好的文本搜索功能等。fbgs 是 fbida 包中提供的一个 PDF 阅读器。它可以设置页面大小、分辨率、指定页码以及绝大部分 fbi 提供的选项，当然除了一些在 man fbgs 中列举出来的不可用选项之外。我主要用到的选项是页面大小，你可以选择 -l、xl 或者 xxl：
$ fbgs -xl annoyingpdf.pdf
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via: https://www.linux.com/learn/intro-to-linux/2018/1/multimedia-apps-linux-console
作者：Carla Schroder 译者：Yinr 校对：校对者ID