CMSC691C Multimedia Networking A Course OverviewList of TopicsThe Telephone (Voice) NetworkThe Internet (Data) NetworkInternet Users GrowthMultimedia over IP NetworksMultimedia Networking ApplicationsMultimedia Broadcast over IPHosted Multimedia StreamingInteractive Conferencing and Meeting ServerHow A Server Distributes the DataDynamic Token PassingMultimedia Signals and BitratesAudio & Video Quality RequirementsIP NetworksMultimedia SignalsImage & Video Coding StandardsA Complete JPEG EncodingFrom Image to Video CodingVideo Coding StandardsMPEG-4: An Emerging StandardHeterogeneous IP NetworksVideo Scalable CodingIP Stack: A Layered ArchitectureIP Packet Routing: Delay and LossQueuing and Scheduling (1)Queuing and Scheduling (2)Queuing and Scheduling (3)Queuing and Scheduling (4)Congestion Control & Queue DiscardSlide 31IP QoS and MultimediaIP Quality of Service (QoS)IETF IP QoS EffortsConnection Oriented QoSIntegrated Services / RSVPConnectionless QoS: IP Diff ServDiffServ OperationMPLS FundamentalsUnicast/MulticastMultimedia IP MulticastIP Multicast Service ModelWhat IPv6 can Offer?IPv6: Key Features and AdvantagesIPv6 Support of QoSExisting Scalable Multicast SolutionsDistributing Content to the EdgesGetting Contents to the EdgeSlide 49Content Distribution Network (CDN)Receiver-driven Layer Multicast (RLM)RLM CharacteristicsSource Adaptive Multi-layer MulticastCMSC691C Multimedia NetworkingA Course OverviewPadma MundurCSEE, [email protected] of TopicsMultimedia Networking: Source Representations, Networks, and Applications Multimedia Compression Fundamentals & Coding StandardsScalable Video Coding for Heterogeneous NetworksFundamentals of IP Routing IETF QoS EffortsExisting Solutions for Scalable Multimedia QoSThe Telephone (Voice) Network•Circuit switched network:–Analog (since1890): manually switching–Digital: voice bit stream (64 Kbps)–Better channel utilization by time-division multiplexing:–Reservation fixed for the whole transmissionABCThe Internet (Data) Network•Packet-switched network:–packets share resources (buffers, links)–reservation not fixed, but on-demand–multiple links (connectivity, reliability)–buffers (store, process, forward)–control information in packets (s,d,seq#)Internet Users GrowthSource: www.isc.org1B mobile users by 2005 and 1B Internet users by 200590% of all new mobile phones will have internet access by 2003 (Morgan Stanley Dean Witter, May 2000)Multimedia over IP NetworksMusic StreamingInformation SearchMoviesStreamingFinance,BrokerageDigital PhotosInternetE-mailVideo ClipAttachmentVideoConferenceVoIPWireless Wireless BrowsingBrowsingMultimedia Networking Applications•Media Broadcast: simultaneous pushing of content to multiple recipients–Network IP Multicast – Multicast enabled routers and switches•Hosted Streaming: content users initiate requests and content networks/providers push content through network•Interactive Conferencing: no centralized source of contentsInternetcontent providerclientsMultimedia Broadcast over IPIP (internet protocol) makes itpossible to link all (global) nodes together independent of applications and terminal devicesHosted Multimedia Streaming MediaEncodingAudioVideoAnimationClientsSend RequestTo ServersWebServerSend Request to Media ServerMediaServerProprietaryFormat•Multicast capable•More Robust•Access to Storage•Relieves Web ServerSend StreamTo Clients•Standalone player•Java based player•Browser plug-in player•Appliance•Decode•Buffer•Sync.To hear or view a media file without downloading itBandwidth concern for multipoint interactionInternetInteractive Conferencing and Meeting ServerMeeting ClientTokenMeeting Token HolderHow A Server Distributes the DataMeeting ClientTokenOld Token Holder New Token HolderDynamic Token PassingMultimedia Signals and Bitrates96 Kbps224 Kbps1.412 Mbps (2 channels)90 Kb/inch26.3 Mb/image248.8 Mbps248.8 Mbps31 Mbps37 Mbps2.3 Mbps121416/channel12424241212128000 samples/sec16,00044.1 Ks/sec300 dpi (dots/inch)512x512720x480x30720x576x25360x240x30352x288x30176x144x7.5200—340050—700020—20,000Telephone VoiceWideband speechWideband audio (2 channels)B/W documentsColor ImageCCIR-601 (NTSC)CCIR-601 (PAL)SIF (standard) CIF (common)QCIF (quarter)Bit RateBits perSampleSamplingRateBandwidth(Hz)SourceAudio & Video Quality RequirementsIP Networks•IP uses packet switching–Suitable for unexpected burst of data without establishing an explicit connection.–Bandwidth is shared statistically so data can be sent at any time.•IP is not reliable nor delay-bounded.–Best effort–Queuing delay, especially when congested.–Network failures can cause temporary packet loss.Time critical applications cannot operate well due to large e-mail attachments and Web surfingDelay and jitter degrade voice and video performanceMultimedia Signals•Text•Speech •Audio•Image (B/W and color)•Video•Graphics & Animation•Documents (various formats)Image & Video Coding Standards•Combination of lossy (transform coding) and lossless (run-length, Huffman, Arithmetic coding, LZW, etc) coding techniques along space and time.•JPEG - Joint Photographic Experts Group•Still image compression, intraframe picture technology•Motion JPEG (MJPEG) is sequence of images coded with JPEG•MPEG - Moving Picture Experts Group•Defined by ISO/IEC, several standards MPEG1, MPEG2, and now MPEG4•H.263/H.263+/H.26L - Videophone/Conferencing•Low to medium bit rate, quality, and computational cost defined by ITU•Used in H.320 and H.323 video conferencing standardsA Complete JPEG Encoding DCTZig-zagQuantizeRun-length CodeHuffman Code011010001011101...From Image to Video Coding•Intra-frame compression (similar to JPEG)•Remove redundancy within frame (spatial)•Inter-frame compression (motion compensation)•Remove redundancy between frames (temporal)•Rate Control (constant bit-rate or constant SNR)Video Coding StandardsMPEG1 – VHS quality, VCD (1992)•CIF images, 4:2:0 sampling, 1.5 Mbs, Frame encodingMPEG2 - broadcast quality, HDTV and DVD (1994)•CCIR 601 images, 4:2:2 sampling, 4-15 Mbs•Interlaced and progressive scanning, Frame and field H.261 for videotelephony (p=1,2) & videoconferencing (p>= 6) (1992)•Improve JPEG through temporal redundancyH.263 – low bitrate video coding (1995)•Half pixel motion compensation, 4 (optional) modes•Optimized VLC tables & better
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