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Video Streaming Dr. Md. Humayun Kabir Assistant Professor, CSE Department, BUET, Bangladesh Overview Streaming Downloading How Streaming works Streaming Contents Different Streaming Technologies Streaming Issues Network Bandwidth Media Compression Real Challenges My Work
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Video Streaming Dr. Md. Humayun Kabir Assistant Professor, CSE Department, BUET, Bangladesh
Overview • Streaming • Downloading • How Streaming works • Streaming Contents • Different Streaming Technologies • Streaming Issues • Network Bandwidth • Media Compression • Real Challenges • My Work • Opportunities • Conclusion Dr. Md. Humayun Kabir
Streaming • Streaming Dr. Md. Humayun Kabir
Streaming • Streaming Dr. Md. Humayun Kabir
Streaming • Streaming Dr. Md. Humayun Kabir
Streaming • Streaming Dr. Md. Humayun Kabir
Streaming • Downloading Dr. Md. Humayun Kabir
Streaming • Streaming vs. Downloading Dr. Md. Humayun Kabir
Streaming • Streaming vs. Downloading Downloading Needs to wait for long time Needs large disk space May violate copy-right Works with low bandwidth Streaming No wait time No disk space requirements Copy-right cannot be violated Does not work with low bandwidth Dr. Md. Humayun Kabir
Streaming • How Streaming Works 1 2 3 4 5 Dr. Md. Humayun Kabir
Streaming • How Streaming Works Step 1: Browser opens a Web Page (HTML File) <HTML> <BODY> < A href=“http://www.web-server.domain.com/demo/a-video.qtl”>Link to a video </A> </BODY> </HTML> Quicktime <HTML> <BODY> <A href="http://www.web-server.domain/demo/a-video.wvx"> Link to a video </A> </BODY> </HTML> Microsoft Dr. Md. Humayun Kabir
Streaming • How Streaming Works Step 2: Web server sends a Meta File (a-video.qtl (.wvx, .wax, .ram)) that contains the following: <?xml version="1.0"?><?quicktime type="application/x-quicktime-media-link"?><embed src="rtsp://streaming-server.domain.com/demo/a-video.mov" /> Quicktime <ASX VERSION="3.0"> <ENTRY> <REF HREF=“rtsp://streaming-server.domain.com/demo/a-video.wmv" /> </ENTRY> </ASX> Microsoft Dr. Md. Humayun Kabir
Streaming • How Streaming Works Step 3: -Web browser reads the meta file and starts the appropriate Media Player -Web browser passes media info (media URI) to the Media Player Dr. Md. Humayun Kabir
Streaming • How Streaming Works Step 4: -Media Player sends RTSP SETUP request to the Media Server using the media URI -Media server replies OK in SETUP response -Media Player sends RTSP PLAY request to the Media Server Dr. Md. Humayun Kabir
Streaming • How Streaming Works Step 5: -Media Server sends OK in RTSP Play response -Media server sends the requested RTP streams (media stream) to the Media Player -After receiving the media stream Media Player plays it Dr. Md. Humayun Kabir
Streaming • Streaming Contents Audio Video Slides with Audio Animation Dr. Md. Humayun Kabir
Streaming • Streaming Technologies Dr. Md. Humayun Kabir
Streaming • Streaming Issues: Bandwidth Bits per second: bps Dial-up: 56 kbps Cable: Downstream 30.3 Mbps to 42.9 Mbps per drop cable; 500 kbps per user DSL: 128 kbps to 51 Mbps PON: 155.52 Mbps to 622.08 Mbps WiFi: 11 Mbps (802.11b:2.4 GHz), 54 Mbps (802.11a: 5GHz), 54 Mbps (802.11g: 2.4 GHz) Bandwidth needed for an uncompressed video with resolution - 720 x 486 x 29.97 is roughly 160 Mbps CD quality uncompressed audio: 1.41 Mbps So, Media compression is must Dr. Md. Humayun Kabir
Streaming • Streaming Issues: Compression H.261: 64 kbps to 2 Mbps H.263: 30 kbps to 2 Mbps H.264: 50-60 kbps (mobile), 1-2 Mbps (Internet, DVD), 5-8 Mbps (HDTV) MPEG-1: 1.5 Mbps (VCD) MPEG-2: 4 Mbps to 15 Mbps (DVD); 80 Mbps (HDTV) MPEG-4: H.264 bit rates MP3: 128 kbps AAC: 16 kbps to 128 kbps; regular 64 kbps Real: 150 kbps to 1 Mbps (standard), 3 Mbps (HDTV) Quicktime: Slightly better than MPEG-4 Windows media: ½ to 1/3 of MPEG-2. Dr. Md. Humayun Kabir
Streaming • Streaming Issues: Real Challenges Bandwidths are constraint Network latency and jitter Compressed Video: variable bit rate with high peaks Streaming media: non-cacheable Streaming service: non-scalable Supporting playback mode switching Dr. Md. Humayun Kabir
Streaming • My Work Invented a new Video Streaming Scheme Conceals network latency and jitter Conceals peak bandwidth requirements of compressed videos Works with any available (low or high) bandwidth Scales well without caching media files Supports different DVD like playback modes Scales well even when different clients are in different playback modes Dr. Md. Humayun Kabir
Streaming • Opportunities: Applications • Video on demand (Cinemanow) • Internet Video (Google Video) • Live/Web Cast • Home Media Center • Kids Entertainment Site • Distance Education • Product Marketing • IPTV • VoIP (IP Phone) • Video Conferencing • Video Phone Dr. Md. Humayun Kabir
Opportunities: Careers Software Engineer-Video Application: Open, RealNetwork, Quicktime, Windows -Videoconferencing/Videophone/VoIP -Streaming Server, Media Player -Video codec - Media Format Converter Hardware Engineer -Video codec/Video card/Converter Dr. Md. Humayun Kabir
Streaming • Opportunities: Careers • Opportunities: Careers • Software Engineer-Video Application-Open Skill Requirements: RTSP, RTP/RTCP, HTTP protocols Network protocols (TCP/IP and others), Socket Codec (MPEG) C, C++ or Java and JMF Windows ActiveX, COM/DCOM or Unix/Linux programming and scripting or Mac OS X programming and scripting HTML, XHTML, XML, JavaScript, ASP/JSP/Perl • Opportunities: Careers Opportunities: Careers Dr. Md. Humayun Kabir
Streaming • Opportunities: Careers • Software Engineer-Video Application-RealNetwork Skill Requirements: Real System SDK Real Helix Server (Streaming Server) C, C++ Windows ActiveX, COM/DCOM or Unix/Linux programming and scripting or Mac OS X programming and scripting HTML, XHTML, XML, JavaScript, ASP/JSP/Perl Dr. Md. Humayun Kabir
Streaming • Opportunities: Careers • Software Engineer-Video Application-QuickTime Skill Requirements: QTKit QuickTime Streaming Server C, C++ or Java Windows ActiveX, COM/DCOM or Unix/Linux programming and scripting or Mac OS X programming and scripting HTML, XHTML, XML, JavaScript, ASP/JSP/Perl Dr. Md. Humayun Kabir
Streaming • Opportunities: Careers • Software Engineer-Video Application-Windows Skill Requirements: Windows Media SDK Windows Media Service (Streaming Server) Windows DirectX SDK C, VC++ Windows ActiveX, COM/DCOM HTML, XHTML, XML, JavaScript, ASP Dr. Md. Humayun Kabir
Streaming • Opportunities: Careers • Software Engineer-Video Application-Videoconferencing/Videophone/VoIP Skill Requirements: SIP and MEGACO or H.323 RTP/RTCP Network protocols (TCP/IP and others), Socket Codec (H.263, H.264, G.711/G.722 etc.) C, C++ programming Windows ActiveX programming or Unix/Linux programming and scripting or Mac OS X programming and scripting Dr. Md. Humayun Kabir
Streaming • Opportunities: Careers • Software Engineer-Video Application-Streaming Server, Media Player Skill Requirements: RTSP, RTP/RTCP, HTTP protocols Network protocols (TCP/IP and others), Socket Codec (MPEG and others) C, C++ or Java and JMF Windows ActiveX, COM/DCOM or Unix/Linux programming and scripting or Mac OS X programming and scripting HTML, XHTML, XML, JavaScript, ASP/JSP/Perl Dr. Md. Humayun Kabir
Streaming • Software Engineer-Video codec • Opportunities: Careers • Software Engineer-Video Application-Video Codec Skill Requirements: Codec (MPEG and others) C, C++ or Java and JMF Windows ActiveX, COM/DCOM or Unix/Linux programming and scripting or Mac OS X programming and scripting Dr. Md. Humayun Kabir
Streaming • Software Engineer -Media Converter • Opportunities: Careers • Opportunities: Careers • Software Engineer-Video Application-Media Converter Skill Requirements: Codec (MPEG and others) C, C++ or Java and JMF Windows ActiveX, COM/DCOM or Unix/Linux programming and scripting or Mac OS X programming and scripting Dr. Md. Humayun Kabir
Streaming • Opportunities: Careers Hardware Engineer -Video codec/Video card/Converter Skill Requirements: Codec theory C, C++ Embedded/Assembly Programming FPGA and ASIC design and programming Dr. Md. Humayun Kabir
Streaming • Conclusion • Basics of Video Streaming • Bandwidth available at different access networks • Different media compression techniques and their bit rates • Problems in streaming • My work in video streaming • Opportunities in streaming technologies Dr. Md. Humayun Kabir
Streaming • Thank You Questions ? Few pictures in this presentation were taken from http://streaming.wisconsin.edu/understand/understand.html Dr. Md. Humayun Kabir