Section 81. About iTunes and Digital Music


81. About iTunes and Digital Music

One of Apple's most legitimate claims to fame today is the digital music system formed by the jukebox application iTunes and the industry-defining family of iPod music players. Hardly anybody on the Internet today hasn't yet heard of these products which have, after years of relative quiet, made Apple into a revered household name once again.

The iPod, iPod mini, and iPod shuffle.

iTunes and the iPod together form a total music management system that lets you acquire and play new music, organize it into playlists, burn it onto CDs, and (using the iPod) put it in your pocket to take wherever you go. The music in question, and the reason for this revolutionary new kind of listening experience, is digital audio . This medium takes the form of either MP3 or AAC audio files that are formed by copying the raw audio data from a digital source (such as a music CD) and compressing it so that each song takes up much less space on your hard diskgenerally between two and six megabytes, as opposed to twenty to sixty megabytes in raw CD formwhile retaining most, though not all, of its sound quality.

Digital Audio Formats

The world has accepted MPEG-1 level 3 (MP3) as the de facto standard format for digital audio; it's versatile, ubiquitous, and mostly free. MP3 files can be played just about anywhere and by anything, from PDAs to cell phones to car stereos. Best of all, they have no Digital Rights Management (DRM) technology. Or, perhaps (depending on whom you ask), that's the worst aspect of MP3 files. MP3s have been the scourge of the commercial music industry in recent years, enabling music enthusiasts to trade songs freely and amass huge collections of commercial music without paying for it. The large record labels demanded a form of MP3-like digital audio that gave users the flexibility they craved, and yet allowed copyright holders to protect their property by only allowing users to make a limited number of copies of the files; they got it in Advanced Audio Coding ( AAC ) , which is a component of the MPEG-4 standard brought to life in part by Apple.

KEY TERMS

MPEG-1 level 3 (MP3) The most widely used format for digital music, MP3 files sound pretty good but have no copy protection built in.

Digital Rights Management (DRM) Software algorithms that provide "copy protection" for digital music, usually enforced with digital "keys."

Advanced Audio Coding (AAC) A new digital audio format co-developed by Apple as part of the MPEG-4 definition; AAC has better quality than MP3, as well as built-in DRM.

Windows Media Audio (WMA) Microsoft's competitor format to AAC, WMA files are similarly higher-quality than MP3s, but their DRM is more restrictive .


AAC files can be as unfettered as MP3 files; for instance, you can use AAC instead of MP3 to encode tracks from CDs that you own. However, AAC also provides copyright holders the optional capability to control who can play them and where; keyed to a centralized database of users and protected with passwords, AAC files can't be copied from one person's computer to another without the files becoming unusable.

It's because of the DRM-protected flavor of the AAC format that the iTunes Music Store has become so popular where other similar ventures without industry-placating safeguards have failed: Built directly into iTunes, the Music Store is an online library of more than a million downloadable tracks in thousands of albums by the most popular commercial artists and obscure cult idols alike. Leading the market by a wide margin, and available in both the Mac and Windows versions of iTunes, the iTunes Music Store lets you buy music through an online account and download it directly into your iTunes Music Library. The purchased music, in AAC format, can be copied and played back on as many as five different computers, whether Windows PCs or Macs. This requires an Internet-based authorization process, however, and without that authorization the files cannot be opened.

Fortunately, AAC brings more to the table than just DRM restrictions; AAC files are smaller and clearer than MP3 files under most circumstances, with true separate stereo tracks and a more efficient codec (encoding and decoding) algorithm. Windows Media Audio (WMA) provides similar features and benefits over MP3, although the DRM infrastructure used in WMA files is more restrictive than what is found in AAC.

The downside of AAC files is that they're not as widely used as MP3 or even WMA files. Nearly all digital audio players can play MP3 files, and many can now handle WMA files as well. However, only the iPod can play AAC files. Considering that the iPod is the world's most popular portable digital music player by a huge margin, though, perhaps that is no drawback.

iTunes

Available for Windows as well as included with every copy of Mac OS X, iTunes is Apple's superstar application, the best current example of the company's vaunted software design sense. Millions of people have discovered it, whether introduced to it with the purchase of a new iPod, or having downloaded it on their own; indeed, it took only three days for a million copies of the Windows version to be downloaded after its introduction. Integrating intuitive playback controls, organizational lists that sort your music into its natural groupings, drag-and-drop playlist creation, one-button CD importing and burning, and the revolutionary iTunes Music Store, iTunes does everything you can imagine doing with your musicand quite likely a whole lot more.

The main iTunes window provides many features associated with recording and playing back audio files.

Interacting with your music in iTunes is generally a straightforward and intuitive affair. However, a few things about its operation might seem surprising at first. First of all, iTunes should not be thought of merely as a "player" for audio files you keep organized in the Finder; rather, it is a separate, specialized interface for your music. iTunes doesn't use the traditional "documents and folders" computing metaphor for organizing music; instead, it treats each individual audio file as a song , and organizes songs on the basis of their artists, albums , and genres , as well as in the custom playlists you can define. You don't " open an MP3 file" in iTunes. Rather, you select a song from iTunes' internal Music Library and play it. The song you select corresponds to an MP3 or AAC file in a folder on your disk, and the folder it resides in is organized according to the artist and albumbut you ideally never have to deal with the files themselves in the Finder in the course of your daily musical enjoyment. iTunes itself keeps track of all that for you.

Playing and controlling music in iTunes is much the same as in the QuickTime Player: The Play/Pause button starts and stops the music, the scrub bar lets you skip immediately to a specific place in a song by dragging the playhead, and the Back and Forward buttons skip from song to song in the current listing. Play a song by double-clicking it in the song list or by selecting it and clicking Play . There's nothing revolutionary about that. Where iTunes shines is in how it organizes your massive music collection and gets you to exactly the music you want.

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If you hold down the Back or Forward button, it will "fast-forward" or "rewind" the song, the same as with most personal music players.


With Library selected in the Source pane, you can browse immediately to an artist to see all the songs in that artist's albums, or to an album directly, by using Browse view (click the Browse button to reveal the navigation lists). The Genre , Artist , and Album lists operate in a manner similar to the Column view of the Finder: Selecting one or more items in one list narrows down which items are shown in the columns to the right (so that if you select Rock from the Genre list, only Rock artists and albums are listed in the other two columns). You can also zoom straight to a song by typing part of its title into the Search box. By sorting the song list by its visible columns of data, you can put all your music in exactly the order you want to play it.

Songs in iTunes' Library all have numerous pieces of data associated with them: Aside from the artist and album and genre, each song ( potentially ) has a track number, a "star" rating that you can assign, a date when it was last played, and many other such fieldsall specified in the info tags (or ID3 tags , for MP3 files) embedded within the file itself. iTunes is really just a big database, managing songs by their info tags, which you can use to sort your songs into automatic ("Smart") playlists, filter them to your preference, and track how often you play them. Through the use of this information, iTunes gradually molds itself to your listening style and preferences.

KEY TERMS

Info tags Data fields built into a digital audio file that contain the song's title, artist, album, track number, album art, and other information. Often called ID3 tags in MP3 files.


The hierarchical structure of the iTunes Music folder.

Behind the scenes, iTunes keeps all its music filesMP3, AAC, and other formats it understandsin a special iTunes Music folder, inside the Music folder in your Home folder. Inside the iTunes Music folder are folders for every artist in the Library , and inside those folders are folders for each album by each artist. MP3 and AAC music files are sorted into those folders, with filenames kept in sync with the info tags you specify for the song name, track number, artist, and album. This way, you can always find your music files quickly using the Finder if you have to. iTunes can also keep track of music files that aren't in its iTunes Music folder, but those files won't be automatically organized if you change their ID3 tags.

NOTE

Mac OS X uses the HFS+ file system, which assigns a "Unique File ID" to each file in the system. Files can be tracked and addressed directly by applications using this ID, rather than by relying on the path through the folders to a file's location. This means that if you add a file to the iTunes music Library , iTunes keeps track of the file by its Unique File ID, not by its path; you can therefore move an MP3 file from one folder to another, as many times as you want, and iTunes won't ever lose track of it. This does not work in Windows.


Chances are that you've used MP3 files at some point in your lifewhether you obtained them commercially, or through ( ahem ) other means. Any MP3 files you might have collected can be used in iTunes, and you can fill in any missing ID3 tags right in iTunes's interface to organize the files better. However, before you can do any of that, you must add your MP3 files to the iTunes music Library . And before you can add audio files to the Library , you must decide how you want iTunes to treat the files. You have two choices:

  • iTunes can automatically copy any newly added audio file to the managed iTunes Music folder; thereafter, the audio file that iTunes uses will be the duplicated one inside its special folder, not your original. If you change the song's info tags in iTunes, iTunes renames the file accordingly and refiles it in the properly named folders. You can do anything you like with the original file; iTunes won't be using it.

  • iTunes can use newly added audio files wherever they are in the system. If you change their info tags within iTunes, iTunes still keeps track of the files, but they are not reorganized or renamed .

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If you elect to let iTunes use audio files wherever they are in the system, you can later decide to copy all your audio files into the organized iTunes Music folder; do this by selecting Consolidate Library from the Advanced menu. This is a one-way operation; it can't be undone. However, it won't change iTunes's behavior for music files you add in the future.


To select the behavior you want, open iTunes (it's in the Applications folder, or click its icon in the Dock), open the iTunes Preferences window (choose Preferences from the iTunes menu), and go to the Advanced tab. Select the Copy files to iTunes Music folder when adding to library check box if you want iTunes to manage its own copies of your files; deselect the box if you want it to use only your original audio files wherever they happen to be.

MP3 and AAC files, by default, are set to open in iTunes. Locate an MP3 or AAC file in the Finder and double-click it; the file opens and plays in iTunes, and a reference to the file appears in the iTunes Library . (Note that if you double-click uncompressed AIFF and WAV audio files in the Finder, the files open in the QuickTime Player rather than iTunes.) If the file's info tags for the song name, artist, and album are set, their contents appear in the song list in the iTunes window, and iTunes can navigate to those songs using the tags.

To add an audio file to the iTunes Library without going through the Finder, you can select File, Add to Library . A navigator window pops up; use this window to locate and select the file you want to add. Click Open to select the file and add it to your iTunes Library

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Select any song in the iTunes Library and choose File, Show Song File (or choose the command from the contextual menu you get if you Control+ click or right-click the song) to open a Finder window showing the folder containing the song file itself. You can then copy or transfer the file, or do anything else that requires you to access the file in the Finder view.


The quickest way to add a file to the iTunes Library is to drag it from the Finder into the iTunes application window, or to the iTunes icon in the Dock. When you release the mouse button, the file is added to your Library .

You can add a whole folder full of MP3 files in this way, tooeven a hierarchical folder full of other folders. Provided that the info tags are set correctly, the files immediately become organized by their artists and albums in iTunes, rather than by their folders and filenames, as they are in the Finder. In fact, if you've got a huge collection of MP3 files on your computer already, you can import them all into iTunes in one motion, by dragging the folder they're in from the Finder into the iTunes window. It will take several minutes for iTunes to reorganize and copy all the files, but all you have to do is sit back and watch until it's done.

NOTE

iTunes does not create duplicate entries in its database for the same audio files. You can drag a file into iTunes as many times as you want, but it will not create an additional entry or lose track of the file. This means you can safely and cleanly add a whole folder full of MP3s, even if you've already added some of the individual MP3 files to the iTunes Library . The Date Added field for those files won't even be updated.


MP3 files you obtain from random sources on the Internet probably don't have all the ID3 tags filled in properlyand this will prevent you from being able to take full advantage of iTunes' navigation methods to find these songs. While the song is selected or playing, simply click in the blank fields of the song in the song list to type in the proper values. Alternatively, press to bring up the Song Info dialog box for the current song; in the Info tab, you can fill in all the info tags directly. Click OK when you're done.

Songs from "compilation" albumswhere each track is by a different artistshould have the Part of a compilation check box selected in the Song Info dialog box. This option allows you to simplify the listing of artists in iTunes; rather than having a dozen new artists added to your Library listing with one song each from a compilation album, you can instead have the entire album show up under the Compilations entry in the Artist column. (You can disable this behavior by using the Group compilations when browsing check box on the General tab of the iTunes Preferences window.) At the same time, at the Finder level, this option causes the audio files from the album to be placed in a single folder named for the album itself, in a folder called Compilations inside iTunes Music (rather than each song being listed on its own in a different folder for each artist).

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Note that this automatic reorganization in the Finder only takes place if you have selected the Keep iTunes Music Folder Organized check box in the Advanced pane of the iTunes Preferences dialog box.




MAC OS X Tiger in a Snap
Mac OS X Tiger in a Snap
ISBN: 0672327066
EAN: 2147483647
Year: 2001
Pages: 212
Authors: Brian Tiemann

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