Another debate: Can digital media match the quality of analog formats? This hardly seems much
of a question anymore because DVD has shown the potential for high-quality digital video, and
MPEG codecs have made huge strides in digital audio fidelity. The quality of digital media files is
very high and getting better all the time. Some of the key technologies that reflect improvements
in how audio and video codecs have improved include:
Ogg Vorbis - This audio codec has been developed as a freely available tool - no
patents or licensing needed. Ogg is the "data container" portion of the codec, and Vorbis
is the audio compression scheme. There are other compression schemes that can be used
with Ogg such as Ogg FLAC, which is used for archiving audio in a lossless format, and
Ogg Speex, which is used specifically to handle encoding speech.
Real Networks - Real has developed a set of audio and video codecs that have an amaz-
ing ability to serve up streaming content. This protocol is not widely supported by any-
one but Real. The Helix project produces a player for Linux that enables playback of
Real media encoded files.
WMA - Windows Media Audio is used to create high-quality digital audio. WMA is
considered a lossless codec, which means the audio doesn't lose quality or data as a result
of repeated compression-decompression cycles. Among its other benefits is that it's one of
the first widely used codecs to support digital surround sound.
WMV - Windows Media Video is used, not surprisingly, to encode and decode video.
This is also a very high-quality encoder and is billed to produce a video that is half the
size of an MPEG-4 encoded video at a comparable quality level.
DivX - This video codec has revolutionized digital video. Extremely high-quality video
can be stored with amazingly small file sizes when using this codec. DivX (Digital Video
Express) is based on the MPEG-4 video standard and can produce 640x480 video that
is about 15 percent of the size of the source DVD material.
Some of these codecs are integral parts of Digital Rights Management (DRM) scenarios. For example,
WMA, WMV, and DivX have elements that support DRM. DRM is basically proprietary copy
protection.
The continuation/full version of this article read on site www.podgrid.org -
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