Playing Music and Video

One of the most popular and enjoyable activities on a computer is playing audio and video. With improved multimedia players and tools for storing and managing content, Linux has become a great platform for storing, playing, and managing your music and video files.

Some Linux distributions are more multimedia-friendly right after the install than others. An example of this is Freespire, which comes pre-loaded and able to support Flash, Java, MP3, Real, QuickTime, and Windows Media files the minute the installation completes. This can save you a great deal of time trying to track down licensing issues and resolve problems. You can find features that are not included with the installation, such as DVD playback support,, at the Linspire Click-N-Run service (www.cnr.com). Ubuntu users can also use Click-N-Run to get both free and commercial software.

Exploring Codecs
If you want to play a video or audio file, you need the appropriate codec installed and ready for use by your media player. A codec is a software-based encoder-decoder used to take existing digital audio/video data and decode the content. Often, codecs use compression technology to reduce the size of the data files while retaining the quality of the output.
If you encounter a media file that you know is a working, playable file and you cannot play the file, you might need to identify and install the proper codec. This often involves installing the proper playback application, such as DivX 5.0.5 for Linux, which installs the MPEG4 codec for video and audio playback.
Many codecs are available, so getting the ones you need is usually not an issue. Advances in codec technology have continued to increase the quality of the encoded content, while reducing file size. Fortunately, most widely distributed videos and audio files (from news sites, for example) are created using a few commonly used codecs. While there are some commonly used encoding standards, there are also a slew of proprietary codecs in use today as well. This is really a battleground of sorts with each vendor/developer trying to produce the superior standard and obtain the spoils of market share that can follow. For the end user,this means you might have to spend time chasing a variety of playback utilities to handle multiple video and audio formats. Another debate: Can digital media match the quality of analog formats? This hardly seems much of a question anymore because DVD has shown the potential for high-quality digital video, and MPEG codecs have made huge strides in digital audio fidelity. The quality of digital media files is very high and getting better all the time. Some of the key technologies that reflect improvements in how audio and video codecs have improved include:
• Ogg Vorbis - This audio codec has been developed as a freely available tool—no patents or licensing needed. Ogg is the “data container” portion of the codec, and Vorbis is the audio compression scheme. There are other compression schemes that can be used with Ogg such as Ogg FLAC, which is used for archiving audio in a lossless format, and Ogg Speex, which is used specifically to handle encoding speech.
• Real Networks - Real has developed a set of audio and video codecs that have an amazing ability to serve up streaming content. This protocol is not widely supported by anyone but Real. The Helix project produces a player for Linux that enables playback of Real media encoded files.
• WMA - Windows Media Audio is used to create high-quality digital audio. WMA is
considered a lossless codec, which means the audio doesn’t lose quality or data as a result of repeated compression-decompression cycles. Among its other benefits is that it’s one of the first widely used codecs to support digital surround sound.
• WMV - Windows Media Video is used, not surprisingly, to encode and decode video.
This is also a very high-quality encoder and is billed to produce a video that is half the size of an MPEG-4 encoded video at a comparable quality level.
• DivX - This video codec has revolutionized digital video. Extremely high-quality video can be stored with amazingly small file sizes when using this codec. DivX (Digital Video Express) is based on the MPEG-4 video standard and can produce 640 × 480 video that is about 15 percent of the size of the source DVD material.
Some of these codecs are integral parts of Digital Rights Management (DRM) scenarios. For example, WMA, WMV, and DivX have elements that support DRM. DRM is basically proprietary copy protection.
The term “DRM” applies to a wide range of technologies that use server-based activation, encryption, and other elements to control who can access content and what they can then do with the content once it has been accessed. While it is very attractive to distributors of audio and video, who are trying to prevent unchecked digital piracy of their content, it can be a real stumbling block for the consumer.
Many DRM solutions require proprietary software and even hardware to work with the protected content. A prime example is the recent production of some DRM-protected audio CDs, particularly in Europe. Some of these disks will not play in older standalone CD players, some will play only on a computer that supports the DRM application on the CD itself, and (especially frustrating) some will not play on a computer at all. In almost all cases, such DRM solutions do not support Linux. Most support only Windows, and a few support Windows and Mac OS X.
Just to make things clear, while the codecs just discussed do not include built-in DRM features, some codecs are specifically designed to integrate with DRM solutions. In other words, all of these codecs can theoretically be used to play encoded content on a Linux system. If the content is protected by a DRM solution, the likelihood that the content is playable on a Linux system is fairly remote. Despite this fact, or perhaps because of it, Linus Torvalds has not excluded the possibility of including support for DRM in Linux. Likewise, several open source projects are working on Linux DRM solutions.