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MP3 was introduced as a part of
the official MPEG-1 standard in 1992 and until today it is the
most successful audio-standard since WAV. The German Fraunhofer
Gesellschaft (FhG), which has developed this audio-compression
still holds the key patents the MP3-techology inherits. The
development started back in 1987 at the Fraunhofer Institut
Integrierte Schaltungen as project EUREKA EU147. The final
compression algorithm became later known as MP3. In April 1989
Fraunhofer applied patent on MP3 in Germany and it became part of
the MPEG-1 standard in 1992. It was in January 1995 when
Fraunhofer applied patent on MP3 in America as well and it was
granted in November 1996. Using MP3-compression PC-users were able
to compress an ordinary music-CD to one tenth of it’s original
size - thus 12 hours of music could be stored on a recordable CD
that on the other hand could be played by a MP3-CD-player or an
ordinary PC. What made MP3 that popular in the end was the online
peer-to-peer program named Napster. Millions of songs were
exchanged every day via the popular program. That was solely
possible by MP3, because conventional formats such as WAV or AU
were way to big in size with similar quality. MP3 also offered
like WMA later the big advantage of being streamable (not all of
the file has to be downloaded to listen to it).
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Microsoft’s respond to MP3, the
Windows Media Audio-standard. As it is part of the Windows Media
package, Windows Media Audio 8 was presented in early December
2000 and it is until now the best Windows Media product.
Windows Media Audio among other things is firmly integrated in
Microsoft’s Windows Media Player.
Microsoft promises with this version almost CD-quality with just a
third of the source-file’s size.
Above all WMA offers the advantage that copyright-protected songs
cannot be published any further (Digital Rights Management).
That’s not the only reason why many music- and movie-corporations
meanwhile decided in favour of WMA instead of MP3. Like MP3 WMA is
almost predestined for the internet by offering streaming
capabilities (see MP3 for details) both with WMA and WMV (Windows
Media Video).
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The development of the OGG
standard began in 1993, then known as “Squish”. OGG was right from
the start an open source project and hence is free of any patents.
It was designed as a substitute for MP3 and WMA and by now it is
almost as popular and well known as MP3. Above all, the algorithm
is still being developed what is mainly due to its flexibility.
Although the sound-quality gets better with every further
development the files are backwards compatible and can be played
with older players as well. Like MP3 OGG offers encoding at
variable bitrates. Using this compression parts of the song are
encoded with a higher compression than others what depends on the
source. Most times, this compression goes along with squishy
noises or even small interruptions. OGG is also one of the very
few formats that support multi-channel compression. Surround-files
could theoretically be compressed with more than two channels. OGG
is, like it’s predecessors, streamable and although the used
player has to support this feature, it’s one of many good reasons
for OGG.
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It was back in 2000 when another
audio-standard was “given birth” and since then struggles for the
users’ favour. VQF however suffers mainly of two things: first it
is hardly known anywhere and second it takes the PC about three to
four times longer to convert a song in VQF than in any other
format.
At a bitrate of 80 kbps VQF promises the same quality MP3 does at
128 kbps - this would mean that VQF-files would take 30 % less
space. Unfortunately it takes twice the CPU-capacity to play VQF
than MP3.
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mp3PRO is the next generation of
MP3. A division of the Fraunhofer Institute is working on
this together with Thomson multimedia. mp3PRO is said to
offer the same quality of MP3 at half the file size. This is
achieved by a further compression of a tone’s high frequencies.
This SBR (Spectral Band Replication) is believed to be almost
loss-less and represents the PRO in the name. Sooner or later
mp3PRO will take the place of MP3 as a common standard. Like WMA
mp3PRO is backwards compatible, that means mp3PRO-files can be
played with common MP3-players. These files however sound very
dull and rustled. In 2001 the new format was first presented to
the public - now like WMA equipped with a watermark for
copyright-protected files. Whether mp3PRO is to take the place of
the worthwhile proven MP3 - no one knows; it’s advantages to
portable MP3-players are obvious. Streaming capabilities surely
prepare mp3PRO for the internet as well.
This format is still being developed. A final release is expected
for the end of 2001.
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After MP3’s marvellous success
especially with the internet-users, the limits of this new format
unveiled quite soon: in lower bitrates MP3 rapidly lost quality
although the file size was reduced remarkably. This is where AAC
comes in. Also developed by the Fraunhofer Institut the
format was meant to be MP3’s successor. However the aim was not
achieved, even at 96 kbps a heavy loss of quality is noticeable.
Maybe that’s why AAC is hardly known anywhere, although it was
introduced in 1999. Above all there are hardly any
software-players that support AAC.
Due to these restrictions AAC was not considered in these test.
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One of the first audio-standards;
WAVE-files are virtually of the same quality as data on audio-CDs
and therefore offer the best quality. At the same time these files
are very large (10 MB / min.), that’s why they are unsuitable for
everyday exchange via the internet.
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