Video-Based Sensor Networks

H. GHARAVIK. Ban

NIST

Video-Based Sensor Networks

Video streaming RTP

Networking Multi-hop/Ad-hoc

Transport Systems IEEE 802.11b

DSSSFHSS

Implementations SPW software implementation to evaluate the network deign iPAQ based experimental setup for real-time demo

Multi-hop Sensor Networks

Requirements;Energy efficientScalable

For an efficient and robust system IEEE 802.11 FHSS is considered.

Implementations & Demos

SPW implementation of 801.11b FHSS for evaluating the performance of the physical

layer under various mobility conditions. receiver design with Viterbi equalizer for

2GFSK, 4GFSK, and 8GFSK signals Antenna Diversity Transmission of video bitstreams Effect of packet loss on the recovered video

Multi-hop ad-hoc Networks

AODV (Ad-hoc on-demand Distance Vector ) routing.

DSR (Dynamic Source Routing)Sensoria Multi-hop Network (WIN NG

2.0)NIST Approach

AODV

It provides loop free routes using sequence numbers associated to each route.

AODV MODULES consists of:Rout request, rout reply, routing table, packet resend, packet capture

SS AA BB CC DDRREQ DRREQ D

XX

To BTo B To CTo C To DTo D

RREP SRREP S

XXREER REER

Sensor Ad-hoc Networking(NIST Demo)

APAP

APAP

APAP

802.11bFHSS

IP

UDP

RTP

H.263

802.11bFHSS

IP

UDP

RTP

H.263

APAP

SensorNetworks

iPAQ

iPAQ

iPAQ

Video Streaming

VIC/RTP package

VIC on iPAQ (Linux) Applied H.263+ compression for low bitrate

video conferencing Developed H.263+-based Error resilient video

decodingPartitionedNon-partitioned

RTP/UDP for low delay video conferencing

PLCP Hdr.PLCP Hdr.

802.11 MAC802.11 MAC FCSFCS

PLCP PreamblePLCP Preamble MPDUMPDU

802.2 LLC802.2 LLC 802.2 SNAP802.2 SNAP

UDP Hdr.UDP Hdr.

RTP Hdr.RTP Hdr.

IP Hdr.IP Hdr.

H.263 video streamH.263 video stream

Payload Hdr.Payload Hdr.

Physical LayerPhysical Layer

Logical Link LayerLogical Link Layer

Network LayerNetwork Layer

Transport LayerTransport Layer

Frame Format for video stream transmitted by Frame Format for video stream transmitted by RTP/UDP/IP with IEEE 802.11RTP/UDP/IP with IEEE 802.11

Solutions

Delivering corrupted packets to the higher layer. Perform packet-loss corrections:

Suitable for multicastUnsuitable for conferencing

Perform error resilient video decoding by taking advantage of the RTP packet sequencing to detect lost packets

Parity check packetParity check packet Data packet-kData packet-k Data packet-1Data packet-1

Video Partitioning

DataDataSplitterSplitterDataData

SplitterSplitter

IEEE 802.11bIEEE 802.11bFHSSFHSS

IEEE 802.11bIEEE 802.11bFHSSFHSS

DataDataAssem.Assem.

H.263H.263VideoVideo

EncoderEncoder

H.263H.263VideoVideo

EncoderEncoder

R = Bitrate (fixed)R = Bitrate (fixed)S = Splitting Percentage RateS = Splitting Percentage Rate

CODEC INDEPENDENTCODEC INDEPENDENT

H.263H.263Video Video

DecoderDecoder

H.263H.263Video Video

DecoderDecoder

Packet-HPacket-H+ FEC1+ FEC1

Packet-LPacket-L+FEC2+FEC2

DelayDelayMUXMUX

DEDEMUXMUXFEC-2FEC-2

DecodedDecoded

FEC-1FEC-1DecodedDecoded

DelayDelay

R.SR.S

R.(100-S)R.(100-S)

Error Resilient H.263 video streaming(SPW Demo)

H.263+

encoderVideoInput

H.263+

decoder

IEEE802.11bFHSS

BitstreamBitstreamre-sync.re-sync.

VideoVideostreamingstreaming

H.263encoder

VideoInput

H.263decoder

IEEE-802.11bFHSS

SplittingSplitting&&

streamingstreaming

BitstreamBitstreamcombine combine

&&re-sync.re-sync.

Pre-Decoder Design(non-partitioned)

videovideobitstreambitstream

BitstreamBitstreamreconstructionreconstruction

ErrorErrorConcealmentConcealmentBufferBuffer

HeaderHeaderExtractorExtractor

Legal H.263Legal H.263bitstreambitstream

ErrorErrorclassificationsclassifications

Self Self ErrorError

DetectionDetection

StandardStandardVideoVideo

DecoderDecoder

VideoVideoDisplayDisplay

FY’02 tasks Complete the 802.11b FHSS

implementation for field tests Performance evaluations in terms of :

• Coverage (indoor/outdoor)• Mobility• Bandwidth• Number of nodes

Further extensions to improve the error resilient decoding of the corrupted bitstream