Quality evaluation of MPEG4 video transmission over GPRS networks..

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Quality evaluation of MPEG4 video transmission
over GPRS networks..

• Presented by
• Abdullah M. Rana
• Multimedia Communication

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Project Overview

• Motivation of the Project
• Multimedia Transmission
• Low bandwidth wireless networks
• Cellular Network infrastructure
• GPRS as the medium
• Applications requiring better audio/video quality
  these wireless networks..
• NS2 Network Simulator
• Evalvid- Quality Evaluation.

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GPRS

• GSM based architecture
• Provision for multi slotting
• IP Network
• Channel Protection Coding schemes (CS1-CS3)
• Packet switched radio transmission
• Suited for bursty applications (e.g. Internet)
• Data rates up to 170 kbps
• Re-uses GSM resources
• Lower call set-up times cheaper
• Scheme Code Rate
  Throughput(bits/ts) Data Rate
• cs-I I /2 6400 9.05
• cs-2 2/3 9880 13.4
• cs-3 3/4 11600 15.6
• cs-4 1 16280 21.4

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GPRS architecture
www.networkdictionary.com/images/gprs.jpg
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Network Simulator NS2

• Event driven simulator
• Split language OTcl and C
• Nodes and links routing algorithms queuing
  schemes
• Protocols TCP, UDP, IP
• Traffic generators CBR, Exponential, Pareto
• Basic mobility support.
• Graphical interface NAM
• Graphs - Xgraph

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Evalvid
hpds.ee.ncku.edu.tw/.../image017.jpg
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Example TCL script

• set ns1 new Simulator
• Creating two nodes
• set node1 ns1 node set node2 ns1 node
• Creating a link between the nodes prop
  delay10ms Drop tail.
• ns duplex-link n0 n1 1Mb 10ms DropTail
• Nodes themselves don't send/receive data. Create
  an agent to do so
• set cbr0 new Agent/CBR
• ns attach-agent n0 cbr0
• create sink
• set null0 new Agent/Null
• ns attach-agent n1 null0
• connect the two agents
• ns connect cbr0 null0
• Tell cbr0 when to start and stop

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Wireless Simulation code

• Set up hierarchical routing.
• Specify topology.
• Create God
• Create a Base Station
• ns_ node-config -adhocRouting DSR
• -llType LL
• -macType 802.11
• -ifqType DropTail
• -ifqLen 100
• -antType OmniAntenna
• -propType TwoRayGround
• -phyType WirelessPhy
• -topoInstance topo
• -wiredRouting ON
• -agentTrace ON
• -routerTrace ON
• -macTrace ON
• -movementTrace OFF

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Wireless Simulation Code

• set BS(0) ns_ node 1.0.0
• BS(0) random-motion 0
• BS(0) set X_ 1.0
• BS(0) set Y_ 2.0
• create mobile nodes in the same domain as BS(0)
  
• ns_ node-config -wiredRouting OFF
• set node_(0) ns_ node 1.0.1
• node_(0) base-station AddrParams addr2id
  BS(0) node-addr
• create and attach Agents TCP/UDP/CBR
• include movement..
• ns_at 10.0 node(0) setdest 200.0 150.0 15.0

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Quality Evaluation..
PSNR MOS Quality Impairment
gt 37 5 Excellent Imperceptible
31-37 4 Good Perceptible/ non annoying
25-30 3 Fair Slightly annoying
20-24 2 Poor Annoying
lt20 1 Bad Very annoying
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Results
File Sizes vs. PSNR FPS 20 , BIT Rate 128KBPS,
Q15, size Qcif
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Results
Frame rate vs. PSNR File Size 10Kb, Bit rate
128 kbps, Q15
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Results
Quantization Scale vs. File size Bit Rate
128Kbps, FPS10, GOP13, Size Qcif, error
resilience4
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Results
Bit rate vs. File Size FPS 10, GOP30, size
Qcif, Q15, error 4
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Results
GOP vs File Size
FPS10, Bit rate5Kbps, Q15,sizeQcif,error4 FPS10, Bit rate5Kbps, Q15,sizeQcif,error4 FPS10, Bit rate5Kbps, Q15,sizeQcif,error4