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DTV Infrastructure from Standards to Startups. Milton Chen. Overview. Ground rules Your DTV station Your DTV receiver. MPEG-2 Transport Stream. 188 byte packets 4+ bytes header sync_byte (0x47) packet ID (13 bits) 0x11, 21, or 31 are video by convention
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DTV Infrastructurefrom Standards to Startups Milton Chen
Overview • Ground rules • Your DTV station • Your DTV receiver
MPEG-2 Transport Stream • 188 byte packets • 4+ bytes header • sync_byte (0x47) • packet ID (13 bits) • 0x11, 21, or 31 are video by convention • 0x14, 24, or 34 are the corresponding audio • transport_error_indicator (1 bit) • transport_scrambling_control (2 bits) • priority (1 bit)
ATSC 8-VSB Data Rate • data rate = 2 * W log ( L ) = 32.286 Mbps • W = 5.381MHz (not 6 because of bandpass filter) • L = 8 levels • 32.286 Mbps * 2/3 * 188/(188+20) * 312/313 = 19.4 Mbps (often quoted rate), 2/3 from Trellis Encoding, 20 from parity bytes • 19.4 Mbps * 184 / 188 = 19.0 Mbps (maximum data rate) • 19.0 Mbps * (65536 – 20 – 8)/65536 = 19.0 Mbps (maximum UDP/IP data rate), 20 byte IP header, 8 byte UDP header
18W 720/60P HD Camera $300k D5 Tape Deck 288 Mbps $150k a site KMRL 28 $4 k DTV File Server 8-VSB Modulator $50k UP Converter $1k Teirnan THE-1HDTV Encoder $200k HD Storage $150k DVB-ASI Dolby PD-567 AC-3 Encoder $3k Audio PES Fiber link Audio Philips Token MUX $25k Tiernan Universal Interface $5k DVB-ASI ASI SkyStream DBN-26 $50k SD camcorder Philips VE98 SDTV Encoder $40k Video PES SMPTE-310 A/D IP Data PSI/PSIP Tables DVB-ASI Microwave link $70 k 250KW IA servers Data Input DVB-SPI IA File Server KICU 52 DTV Station b site Internet T1
Your DTV Receiver Intel Video API Intel ATVEF API Intel Transport API IP Multicast API Intel DTV Driver (K2) Hauppauge/Philips receiver board (Coney/Maui) Linux and Windows Windows
Intel Transport API • Channel Tuning • DTVInitFromATSC (channel) • DTVInitFromFile (file,bitrate,loop ) • class DTVConn { DTVConn ( pid, raw ); int RetrieveBuffer ( buf, wait ); int ReturnBuffer (buf ) int Flush();} • Utility Tools • VSBM, DTVStat, iDTVtest, DTVRec, Dmon, DTVSim
Intel Video API • MPEG Processing Library (MPL) • Access to decoded video frames and much more • Highly optimized codec • path to OpenGL video texture • DirectShow wrappers
IP Multicast API • Standard Winsock programming • Run DTVSock.exe to enable data flow • Likely to be supported by all PC DTV cards • Hauppauge/Philips • Creative Labs/Teralogic • Broadlogic • Realtime back channel to complete the loop
Advanced Televison Enhancement Forum (ATVEF) • Framework for interactive TV over ATSC, NTSC, and Internet • Based on WEB standards • HTML, JavaScript • Use IP to transport all data • Uni-direction HTTP • All-or-none • Error correction • Object segmentation • Naming scheme for cached data • At least 1MB of data cache in receiver
ATVEF (2) • Announcements • address 224.0.1.113 and port 2670 • describe the enhancement and what IP addresses to listen for triggers and resources • Triggers • 1 UDP packet • Resources • web pages, images, scripts, gzipped data
Producing Your Content • Capturing Video • camera, camcorder • Editing Video • Adobe Premiere, Avid Express • ATVEF • WEB tools • Intel Broadcast Plus Tools • scripts • MPEG2 Transport Stream • Intel’s Dynamux.exe (software mux) • Other ...
What Next • Programming session • Next Monday night • Tools and sample codes • Most systems at three months before tradeshow stage • Tell me what you need