Windows Media Audio

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Windows Media Audio Video 9 Series

• ??? ??
• Technical Specialist
• Microsoft Korea

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WM Audio Video 9 Series Key Design Pillars
Best Video

• Improve quality at all rates
• Enable HD playback
• Improved decoding performance
• Enable hardware (encode/decode) implementations

Best Audio

• Improve quality/efficiency
• Extend the family to multi-channel/high
  resolution audio
• New innovation in voice and music compression

Support for Embedded Devices

• Enable efficient hardware implementations
• Strong collaboration with partners for both PC
  peripherals and non-PC devices/chips

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WM Audio Video 9 SeriesNew family of codecs

• Windows Media Video 9
• Windows Media Video 9 Professional
• Windows Media Video 9 Screen
• Windows Media Video 9 Image

• Windows Media Audio 9
• Windows Media Audio 9 Professional
• Windows Media Audio 9 Lossless
• Windows Media Audio 9 Voice

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Windows Media Video 9

• State-of-the-art Video compression engine
• Great quality from wireless ? dial-up ?
  high-definition video
• 160x120 _at_10kbps ? 1920x1080 (1080i/p) _at_ 3-20
  Mbps
• Superb compression efficiency
• Three times as good as MPEG-2
• Windows Media HD Video (1280x720p) at SD DVD
  rates (4-6 Mbps)
• Windows Media SD Video at DVD resolution
  (720x480p) at 2 Mbps (vs. 6 Mbps)
• Twice as good as MPEG-4
• 15 to 50 improvements over WMV 8
• New professional level profiles for high data
  rate SD and HD
• Broadcast-ready
• Support for native-interlacing

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Windows Media Video 9 Video Smoothing (Frame
Interpolation)

• Generates missing frames at playback time
• Can double or triple the decoded frame rate
• Improves perceived video quality/motion
  smoothness
• Especially useful at lower data rates where full
  frame rate is difficult to achieve
• Technology can also be used to save bandwidth
• Video can be encoded at lower data/frame rate
• E.g. ICP encodes 15 frames/sec, but user of WM9
  Player will experience 30 fps
• Bandwidth reduction reduces operating cost for
  ICPs

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Windows Media Video 9DEMO

• vs. QuickTime 6/MPEG-4 Video Smoothing

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Windows Media Video 9 Screen

• Highly efficient compression engine for
  palletized video
• Typical scenario is capturing application/desktop
  output for training/demo
• Entire desktop can be compressed and transmitted
  at rates as low as 28kbps!
• Original Version (V7) shipped in 2000
• Version 9 improves in both picture quality and
  CPU usage
• More efficient handling of continuous-tone images
  and window dragging/scrolling
• Results in far higher frame rate

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Windows Media Video 9 ScreenDEMO

• WMV 9 Screen

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WMA 9 Professional

• New high-performance audio codec to handle
  greater than CD resolution/channels
• Up to 96Khz sampling rate, 24-bits, and 8
  channels (7.1)
• CD is stereo at 44Khz using 16-bit samples
• Target application is multi-channel music
  distribution and movie sound tracks at broadband
  rates
• Current multi-channel unsuitable due to high data
  rate
• E.g. minimum of 384kbps for Dolby
• Leaves too little for video on typical DSL/cable
  connection
• WMA Pro can handle 5.1 from just 128kbps
• Multiple encoding modes including 2-pass/VBR

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WMA 9 ProfessionalDEMO

• WMA 9 Professional
• 192K WMA Pro 5.1 vs. 192K MP3

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Windows Media Audio 9 Lossless

• Mathematically lossless audio compression
• Rip once preserves full fidelity of the
  original
• Decoded stream matches the original bit-for-bit
• Customers no longer have to worry about ripping
  with ever improving audio codecs
• Range CD resolution to 24-bit/96Khz/7.1
• Compression ratio is 21 for CD source
• Good fit for ever increasing PC hard disks (200
  CDs in 50GB hard disk)
• Competitive with top lossless audio codecs, e.g.,
  Monkey, LPAC, MLP (DVD-Audio)
• Compression ratio improves as resolution/sampling
  rate/channel count increases because of increased
  redundancy
• Integrated into Windows Media Player 9 CD copy
  function

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Windows Media Audio 9

• Third iteration of backward compatible
  improvements to WMA
• 20 quality improvement over WMA 8 without
  changing decoded stream syntax
• Compatibility key to satisfying non-PC
  devices/partners
• New encoding modes deliver even better sound
• Quality-based VBR mode
• User can select quality instead of bit rate
• Perceptually lossless mode
• Highest quality VBR encoding mode
• Indistinguishable from the original even for most
  audiophiles
• Typical compression ratio of 51
• Available as a ripping option in Media Player 9
• 2-pass mode, applies to both CBR and VBR

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Windows Media Audio 9 Voice

• Unique hybrid voice and music coder for low
  data rates (lt 20Kbps).
• First codec to properly handle mixed mode content
  (e.g. news plus musical commercial)
• Uses an auto/manual classifier to detect
  voice/music
• Applies appropriate coding mode for each segment
• Voice mode new proprietary voice codec
• 20 better than ACELP shipping today (used by
  Real and WM)
• Music mode WMA algorithms

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WMA 9 VoiceDEMO

• WMA 9 Voice

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Windows Media Audio Video 9Summary

• Great video quality from low bit rates to HD
• 2x better than MPEG-4, 3x better than MPEG-2
• Enhanced Screen codec
• Unique Video Smoothing
• Rich family of audio codecs with best quality in
  industry
• Multi-channel/high-res audio from 128-768 Kbps
• Improved WMA 9 backward compatible codec with VBR
• First hybrid speech/music codec
• Strong momentum in device space
• 130 devices support WMA
• 30 partners designing/porting WMV 9 encoders and
  decoders

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Questions?
17
Backup
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Audio Video Compression Industry Comparison
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Windows Media Audio Video 9 Device Strategy

• WMA bit stream syntax already frozen for three
  years
• Key requirement for hardware implementation
• Many decoder chips/ports already available
• 130 non-PC devices support WMA
• WMV 9 bit stream syntax frozen for the first
  time
• Actively working with 30 hardware partners for
  decoders and encoders
• Many target applications from DVD players to STBs
  and video appliances
• DirectXVA hardware acceleration of WMV 9 decoding
  in graphic cards from all major manufacturers
• Broad licensing program available for both

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Windows Media Video 9 Image

• New codec which enables still images to be
  transformed into full screen video using pan and
  zoom effects
• Cross dissolve transitions can be added between
  clips
• Results can be delivered at data rates as low as
  20kbps
• Compressed using either 1-pass CBR or VBR, they
  can be shared as they are much smaller than the
  original images