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MP3 is the most popular audio format for storing and listening to music.But
there are also many other popular audio formats on the Internet,such as
WAV,WMA,OGG and so on. Maybe you need to understand the differents between
them.Here are the most popular types.
CDA (*.cda)
CDA(CD Audio) format is developed by Philips in the 1970's.It is the most
popular audio format used in CDs.
CDA choose A sample rate of 44,100 samples per second (44.1 kHz),Each
"sample" is a 16-bit number, ranging from -32,768 to 32,767.which
means the best audio quality. But,you can not play CDs without CD-ROM
or special CD player. So, CD Ripper is needed. CD Ripper can help you
to convert CDs to other audio format.
WAV (*.wav)
WAV is the IBM/Microsoft sound format,it is used in Windows and supported
on Macs and works in all web browsers. Wave files can have various sample
rates, sizes and channels,But ,thay are not compressed and tend to create
large files.Approximately 10 MB to store just one minute of CD-quality
audio (44100Hz, 16 bits).
Table 1. Sample and Size (per minute):
| |
8
bits |
16bits |
| Sample |
Mono |
Stereo |
Mono |
Stereo |
| 11.025 Khz |
0.66MB |
1.32MB |
1.32MB |
2.65MB |
| 22.050 Khz |
1.32MB |
2.65MB |
2.65MB |
5.29MB |
| 44.100 Khz |
2.65MB |
5.29MB |
5.29MB |
10.6MB |
MP3 (*.mp3 *.m3u)
MP3(MPEG Audio Layer-3) belongs to MPEG(Movie Picture Expert Group),which
developed by Fraunhofer IIS in Germany and University of Erlangen in 1987(http://iis.fhg.de).
It is a compressed, lossy, audio format that reduces file size to less
then 10% the size of a .WAV file while still maintaining good sound quality.
in 1998 Fraunhofer began asking companies who use MP3 technology to pay
licesne fees and royalties. As a reaction to this, work has started on
a royalty-free Ogg Vorbis format.
Table 2. MP3 quality:
(Bitrate)
kbps
|
Quality |
Size
(per minute) |
| 1411 |
CD |
10.6 MB |
| 192 |
Excellence |
1.44 MB |
| 160 |
Excellence |
1.2 MB |
| 128 |
Very Good |
0.96 MB |
| 112 |
Good |
0.84 MB |
| 96 |
Good |
0.72 MB |
| 64 |
FM |
0.48 MB |
| 32 |
AM |
0.24 MB |
WMA(*.wma)
WMA stands for Windows Media Audio 8 encoding,developed by Microsoft.
Microsoft's Windows Media Player 8, which chairman Bill Gates expects
to rival MP3 in audio and video quality. Microsoft says the latest version
of Windows Media offers near-CD quality audio formatting at 48 kilobits
per second. Microsoft also claims to have tripled the audio compression
of MP3s, making it possible to store three times as much music on space-challenged
hard drives and portable audio devices.
Ogg Vorbis(*.ogg)
"Ogg Vorbis is a fully Open, non-proprietary, patent-and-royalty-free,
general-purpose compressed audio format for mid to high quality (8kHz-48.0kHz,
16+ bit, polyphonic) audio and music at fixed and variable bitrates from
16 to 128 kbps/channel. This places Vorbis in the same competitive class
as audio representations such as MPEG-4 (AAC), and similar to, but higher
performance than MPEG-1/2 audio layer 3, MPEG-4 audio (TwinVQ), WMA and
PAC.
Vorbis is the first of a planned family
of Ogg multimedia coding formats being developed as part of Xiph.org's
Ogg multimedia project." (from http://www.xiph.org/ogg/vorbis/)
=The End=
( NOTE: ) Allow everyone to reprint this article in any form.However,
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See Also:
http://grahammitchell.net/writings/vorbis_intro.html
http://164.116.21.67/atech/multmed/mmaudio02.php
http://www.sinica.edu.tw/~ez2cclin/acoustic/%AC%DB%C3%F6%AE%E6
%A6%A1%A4%B6%B2%D0.html
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