Download - Video/Image Processing
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