CISCO S3000/S5000 SERIES MEDIA PROCESSORS
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Understanding VC-1
Cisco Media Processor supports the following video profiles:
VC-1 Simple Profile (WMV3)
VC-1 Main Profile (WMV3)
VC-1 Advanced Profile (WVC1)
Files encoded according to these profiles are identified by their Four Character Code
(FOURCC). The FOURCC identifier is located at the beginning of a digital media file
and tells the system what libraries to utilize for decoding the file. Note that these profiles
are also equivalent to Windows Media 9 Video Simple, Main and Advanced.
VC-1 codec specification
The VC-1 standard was approved by SMPTE and is referenced as SMPTE 421M.
Although VC-1 and WMV9 refer to the same codec technology as far as Microsoft is
concerned, VC-1 is actually a superset of WMV9, containing more coding tools for
interlaced video sequences than the original WMV9 codec which concentrated on
progressive encoding for computer displays. The main goal of VC-1/WMV9 Advanced
Profile development and standardization was to support the compression of interlaced
content without first converting it to progressive, making the codec more attractive to
broadcast and video industry professionals. Leading content companies, solutions
providers and consumer electronics manufacturers are adopting Windows Media Video
9 (VC-1) to drive the widespread delivery of high-definition experiences to consumers.
VC-1 has been accepted by both of the next-generation DVD committees, HD-DVD and
Blu-ray Disc.
VC-1 contains a number of profile and level combinations that support the encoding of
many types of video. The profile determines the codec features that are available, and
determines the required decoder complexity. VC-1 supports the following three profiles:
Simple, Main, and Advanced. The Simple and Main profiles have been complete for
several years, and are most commonly referred to as WMV9. The completion of the
Advanced profile and consequent standardization of all profiles in the VC-1(SMPTE
421M) spec represents the final step in a comprehensive specification that delivers high
definition content—either interlaced or progressive—across any medium and to any
capable device.
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