About Ogg, Theora, Vorbis and FLAC

The newest version of Ubuntu, Feisty Fawn, prompts you to install proprietary codecs when trying to play e.g. an MP3 file. It displays the following message:

The use of some of this software may be restricted in some countries. You must verify that one of the following is true:

1. These restrictions do not apply in your country of legal residence
2. You have permission to use this software (for example, a patent license)
3. You are using this software for research purposes only

The reason Ubuntu, and Xubuntu, cannot ship these “codecs” (software that allows you to play media in a certain format) is that several companies claim to own patents over these codecs and have been enforcing these patents. You can read more about these issues concerning MP3 at the Wikipedia page on MP3.

Of course there are alternatives to these formats which, if your preferred media player supports it, I highly recommend you to use. However, to be able to use them, you need to know how to, so in this post, I’ll try to highlight the popular alternatives. Note that I am far from an expert in this area, I’ve just done a little research.

There are two ways to save an audio file: lossy and lossless. Lossy means that, when saving an audio file, everything that the human ear cannot hear will not be saved, resulting in a considerably lower file size. Of course, the quality is reduced a little, and the removed sounds cannot be restored unless you have a backup, but the loss is not noticeable unless you are trying very hard. This is also the reason that it is unwise to convert your files from one lossy format to another, as the quality will be greatly reduced. As you might have guessed, lossless audio formats save the file without any loss. As a result, the file size is much larger than for lossy audio formats, though it can be reduced a little by some lossless formats.
WAV is, as yungchin tells us, a container format that most often stores pulse-code modulation, a way of digitally storing a close representation of an analog signal such as sound, together forming the most common lossless audio format. As far as I know WAV is not restricted by licensing issues in that it can come default on Xubuntu, but it is not open, as in free to edit. The most popular open alternative is Free Lossless Audio Codec (FLAC). Another advantage of FLAC over WAV is that FLAC, even though it loses no data, still manages to compress the audio file resulting in a little smaller file sizes.

The most common lossy audio format, which I’m sure you’ve heard of, and which I mentioned earlier, is MPEG-1 Audio Layer 3. If you haven’t heard of it, then you probably know it by the name MP3. This one not only isn’t open, but also cannot be supported by default in Xubuntu. The most popular alternative is Vorbis, which is half the size but of better quality, like Microsoft’s Windows Media Audio (WMA). Vorbis is mostly used in combination with another format, within a container format called (thanks Bas) Ogg, and then referred to as Ogg Vorbis. To add to the confusion, it sometimes (mostly) is also referred to as simply Ogg. And it gets worse: Theora, an open video format alternative to MPEG-4 Part 14 (or MP4) which is also used in conjunction with Ogg, is also sometimes referred to as simply Ogg, and both use the .ogg extension!
So, when someone mentions Ogg, it is likely to be Ogg Vorbis when he refers to an audio file, and Ogg Theora when it’s a video file.

The Free Software Foundation recently started the Play Ogg campaign, which promotes the use of Ogg instead of MP3. As you can see on their, they mention “Ogg” all the time whereas they mean “Ogg Vorbis”.

If you want to dig yet a little deeper, you might also want to check out Wikipedia’s article on Speex, another format used with often contained in Ogg… In fact, even FLAC can be contained in Ogg, but this is not that common.

Now, on to converting your audio files to these open formats. The software you can use for this is SoundConverter, which you can install by opening Add/Remove… in the Applications menu under System. Make sure you have selected to Show: either “All Open Source applications” or “All available applications”.

When you start SoundConverter from “Multimedia” under the “Applications” menu, you will be greeted with the following screen:

Before converting, you should check the Preferences under the Edit menu, where you can set the format to convert to, the quality of the newly produced file, and where to save it:

After you have set your preferences, you can start adding files that you want to convert to the format you just selected. You can add whole folders at once, or add files one by one:

When you are done adding files, click “Convert” to start the conversion process:

That’s it, you now have your sound files in a shiny other format!

PS. As I said, I’m not an expert, so if anyone has anything to add (preferably backed by sources) please do so in the comments on this post.