Multimedia Computer Technologies

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Multimedia ComputerTechnologies
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Multimedia PC

• The MPC aims
• to deliver a combination of high quality
  graphics, sound, and pictures to the home user,
• preferably at a reasonable price, all in a
  computer environment where it can be manipulated
  by the customer
• MPC Level 3 Specification (1995/1996)

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Video and Graphics

• VGA (Virtual Graphic Array)
• Resolution 720x480 pixels, 256 colors
• SVGA
• Resolution 1280x1024 pixels, up to 32-bit colors
• Video playback
• Sent to graphic controller after decompression
• 30 fps for resolution 352x240 pixels
• Or 25 fps for resolution 352x288 pixels

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Audio

• 8-bit or 16-bit samples with a sampling rate of
  8, 11.025, 16, 22.05, or 44.1 KHz
• Linear PCM codec
• Playback or recording of 16-bit stereo
• CD-ROM drive with CD-Digital Audio, Redbook
  (CD-DA) outputs and volume control
• At least two Speakers and a subwoofer
• A MIIDI(Musical Instrument Digital Interface) port

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Telephony (1)

• CTI (Computer-Telephony Integration) applications

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Telephony (2)

• Windows supports TAPI (Telephone), TSPI
  (Telephone Service Programming Interace), MAPI
  (Messaging), SAPI (Speech), MCI (Media Control
  Interface)

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Videoconferencing
Network Standards Video Audio Data
ISDN H.320 H.261 G.711, G.722, G.728 T.120
GSTN H.324 H.263, H.261 G.723 T.120
LAN/Internet H.323 H.263, H.261 G.711, G.723, G.722, G.728 T.120
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TV and Radio
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Compact Disks (1)

• CD-DA Digital Audio (1980)
• Access rate 150 Kbps, sampling rate 44.1 KHz,
  storage 682 MB
• CD-ROM (1985)
• To store mixed text, data, video and audio
• Access rate 150 Kbps(1X) 24 x 150 Kbps (24X)
• CD-I Interactive (1986)
• For real-time playback of multimedia and
  interactive games
• Stores mixed text, graphics, video and audio for
  high-speed information retrieval
• Handles synchronization among interleaved data,
  compressed audio, still frames and full-motion
  video files

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Compact Disks (2)

• DVI Digital Video Interactive/Initiative (1986)
• Use Indevo (Intel Video) a proprietary
  compression method
• Non real-time compression, real-time
  decompression
• CD-XA Extended Architecture (1989)
• Improves CD-ROMs video and audio capability
• Contains mixed test and data with audio and video
  (similar to CD-I)
• Compliant to CD-ROM, CD-I
• PhotoCD
• Store max. 100 compressed photos
• Uses same format as CD-XA

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Compact Disks (3)

• Video CD (1993)
• Full-motion video (MPEG-1)
• Stores 74 minutes of video
• CD-R Recordable (1990)
• Permits appending information to the previously
  recorded information
• MPC Level 3 specifies that the CD-ROM must read
  CD-DA, CD-ROM, CD-XA, CD-I, Video CD, CD-R, Photo
  CD, CD Extra.

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Compact Disks (4)

• DVD Digital Video Disk
• Larger storage space 682MB ? 4.7 17 GB
• Shorter pit length 0.834 ? 0.4 micron
• Tighter track spacing 1.6 ? 0.74 micron
• Shorter wavelength laser 780nm ? 635 650 nm
• Store anything a CD is capable of holding
• Even MPEG-2 and Dolby AC-3

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USB Universal Serial Bus

• Plug-in devices without configuring
• Support almost peripherals
• USB 1.1 1.5Mbps, 12Mbps
• USB 2.0 400Mbps

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IEEE 1394 FireWire

• Hardware and software standard for transporting
  data at 100/200/400/800 Mbps
• Industry
• Accepted as the standard digital interface by
  Digital VCR Consortium
• Digital Video Broadcasters have endorsed IEEE
  1393 as Digital TV(DTV) interface
• Proposed 1394 to VESA for Digital Home Network
  media
• EIA 4.1 subcommittee has voted for 1394 as the
  point-to-point interface for DTV multipoint
  interface for entertainment system
• ANSI has defined Serial Bus Protocol to
  encapsulate SCSI-3 for 1394

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IEEE 1394 FireWire

• Why 1394?
• Digital Interface No need to convert digital
  data into analog and tolerate a loss of data
  integrity
• Physically small Thin serial cable
• Easy to use no need for terminator, device Ids,
  or elaborate setup
• Hot pluggable users can add or remove 1394
  devices with bus active
• Inexpensive priced for consumer products
• Scaleable architecture support daisy chaining
  and branching to true peer-to-peer communication
• Non-proprietary no licensing problem to use for
  products

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IEEE 1394 Standard

• 13941995
• Support up to 400 Mbps, 6 pin cables
• 1394a 1998
• Power management clean up
• Open Host Controller Interface 1998
• Single driver for OS
• 1394b 1999
• Speed increase to 3.2 Gbps
• Support distance of 100 meters
• Significantly reduces latency times by using
  arbitration pipelining

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IEEE 1394 Usage Growth
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IEEE 1394 Protocol Stack
Serial Soft API
Configuration Error Control
Read, Write, Lock
Transaction Layer
Isochronous Channel
Packets
Link Layer(Cycle control, Packet Transmitter,
Packet Receiver)
Serial Bus Management
Symbols
Physical Layer(Encode/Decode, Arbitration, Media
Interface)
Electrical Signal Mechanical Interface
IEEE 1394 Physical Interface
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IEEE 1394 Protocol Stack

• PHY Layer
• Physical layer provides initialization and
  arbitration services
• Assures that only one node at a time is sending
  data
• Electrical signaling, mechanical connectors
  cabling, arbitration mechanism, serial coding
  decoding, transfer speed detection
• Link Layer
• Gets data packets, Error detection correction,
  Retransmission
• Handles provision of cycle control for
  Isochronous channels
• Supplies an acknowledged datagram to the
  Transaction Layer
• Transaction Layer
• Request-response protocol
• Requires conform to
• IEEE 1212, Control Status Register(CSR)
  architecture

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IEEE 1394 Data Transfer

• Asynchronous
• Targeted to a specific node with an explicit
  address
• Not guaranteed a specific amount of bandwidth on
  the bus
• Data is sent in one direction followed by
  acknowledgement to the requestor
• Isochronous
• Broadcast in a one-to-one or one-to-many fashion
• No error correction nor retransmission
• Up to 80 of the available bus bandwidth can be
  used for Isochronous transfer
• Data channels provide guaranteed data transport
  at a pre-determined rate
• Delegation of bandwidth is tracked by a node
• Especially important for time-critical multimedia
  data where just-in-time delivery eliminates the
  need for costly buffering

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USB 2.0 vs. IEEE 1394

• USB 2.0 is the preferred connection for most PC
  peripherals
• 1394s primary target AV CE, DVD, DVCR, DTV
• Both USB 2.0 1394 are expected to co-exist on
  many consumer systems in the future
• USB requires a CPU to perform the bus master
  function while 1394 is peer-to-peer
• USB throughput is not nearly as fast as
  advertised
• When shipping data directly from a peripheral to
  host, OK
• When shipping data from a peripheral to another
  peripheral, real bandwidth drops in half
• All data must be moved from the peripheral to the
  host and then from host to the target peripheral

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USB 2.0 vs. IEEE 1394

• USB 2.0 hubs are more complicated
• Require entire USB 1.1 HOST controller and a new
  USB 2.0 hub controller
• Require high-speed signal repeater, routing
  logic, dual function port
• 1394 is for device where the high performance is
  a priority and price is not
• USB is for device where price is priority and
  high performance is not

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Multimedia Processor

• Intel MMX technology
• Uses single instruction, multiple data (SIMD)
  architecture to process multiple data bits
  simultaneously
• 1.5 times faster for MPEG-1 video decoding