User guide

Page 26
Digital audio terms
MP3
MPEG-1, Layer 3 Audio (MP3) is a compressed digital audio file format. This format allows
for near CD quality sound, but at a fraction of the size of normal audio files. MP3 conversion
of an audio track from CD-ROM reduces the file size by approximately a 12:1 ratio with virtu-
ally no loss in quality. This digital sound encoding and compression process was developed
by the Fraunhofer Institut fur Integrierte Schaltungen and Thomson Multimedia. MP3 uses
perceptual audio coding and psychoacoustic compression to remove the redundant and irrel-
evant parts of a sound signal that the human ear doesn’t hear. It also adds a Modified Dis-
crete Cosine Transform (MDCT) that implements a filter bank, increasing the frequency
resolution 18 times higher than that of layer 2. The MP3 encoding process is well suited for
the transfer of high quality audio files with small file size over the Internet.
Playlist
Playlists let you organize lists of tracks to play in the order you choose. Playlists make it eas-
ier to manage large collections of music.
Ripping
See Encoding.
SDMI
The Secure Digital Music Initiative (SDMI) is a forum of over 130 companies in the fields of
recorded audio content, computers, and consumer electronics, for the purpose of developing
an integrated method of copyright protection technology that can be used worldwide. SDMI is
working to create a framework for preventing improper usage of audio files and to promote
legal music distribution services.
Skin
The skin is the software option that determines how digital audio player software applications
appear on your computer screen. Some applications allow you to customize the color and
window design of your software by changing the skin. Some skins omit certain playback con-
trols for simplicity.
USB
Universal Serial Bus (USB) is the external bus standard that supports data transfer rates of
12 Mbps (12 million bits per second). The Rio uses USB to communicate with the computer.
A single USB port may be used to connect up to 127 peripheral devices, such as mice,
modems, and keyboards. USB also supports Plug-and-Play installation and hot plugging. It is
expected to completely replace serial and parallel ports.
WMA
Windows Media Audio (WMA) is the compressed audio format created by Microsoft as an
alternative to MP3. WMA may replace MP3 since it offers greater file compression—twice
that of MP3—at the same or better sound quality.