White Paper
M600
37
February 2006
Video formats
WAV
A wave file is identified by a file name extension of WAV (.wav). Used primarily in PCs,
the wave file format has been accepted as a viable interchange medium for other com-
puter platforms, such as Macintosh. This allows content developers to freely move
audio files between platforms for processing.
In addition to the uncompressed raw audio data, the wave file format stores information
about the file's number of tracks (mono or stereo), sample rate, and bit depth.
XMF
Xtended Music Format
XMF is a technology for collecting other music and sound resources, such as Standard
MIDI Files, DLS instrument files, WAV or other digital audio files. XMF does not
describe musical notes, notation, instrument sounds or audio recordings. Instead, it
allows content creators a method to collect all those elements and put them in a single
file. In the end, this means easier handling and more consistent predictable playback.
DLS
The DLS file format is used to store both the digital sound data and articulation param-
eters needed to create one or more 'instruments.' An instrument contains 'regions'
which point to WAVE 'files' (samples) also embedded in the DLS file. Each region spec-
ifies a MIDI note and velocity range which will trigger the corresponding sound and also
contains articulation information such as envelopes and loop points. Articulation infor-
mation can be specified for each individual region or for the entire instrument.”
Real Audio 9
RealAudio is a proprietary encoding format from RealNetworks. It also supports reposi-
tioning during real-time playback.
eACC+
(EACC+, ACC+
V2)
eACC+ is ACC+ with the addition of Parametric Stereo (PS). PS significantly increases
the codec efficiency for low bit rate stereo signals.
ACC+
(HE ACC, ACC+)
‘High-efficiency ACC’ is the official MPEG name for the combination of ACC and Spec-
tral Band Replication (SBR). SBR is a bandwidth extension technique which enables
audio codecs to deliver the same quality at half the bit rate.
Format
Description
MPEG-4 ISO File Format (.mp4), ISO/IEC
14496-14, including MPEG-4 AAC-LC
and AMR-NB audio.
File formats that are specified as a part of the ISO/IEC MPEG-4
international standard. It is used to store media types defined
by the ISO/IEC Moving Picture Experts Group, and can be
used to store other media types as well. It is, typically used to
store data in files, though it will be used in data streams and
possibly in other ways. *.mp4 allows multiplexing of multiple
video and audio streams in one file, variable frame- and bit-
rates, subtitles and still images. It also allows streaming over
the Internet.
3GPP File Format (.3gp), 3GPP TS
26.234 V5.6.0, including MPEG-4 AAC-
LC and AMR-NB audio
File formats which are used in mobile phones to store media
(audio/video). This file format is a simpler version of "ISO
14496-1 Media Format”. This format can only carry video
encoded as MPEG-4 or H.263. Audio is stored in AMR-NB or
AAC-LC formats
RealMedia
A digital sound and video file format that is the registered
trademark of RealNetworks. This format is typically used to
stream media through the net.
