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Broadcast Television Archiving. Rod Hewitt rod@coolstf.com. Current System. Analog input-based Encodes to MPEG-2 Program Stream files Initially DLT tape based Now uses removable 3.5 inch drives Operational since 2000. Current System. Records up to twenty channels on five PCs
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Broadcast Television Archiving Rod Hewitt rod@coolstf.com
Current System • Analog input-based • Encodes to MPEG-2 Program Stream files • Initially DLT tape based • Now uses removable 3.5 inch drives • Operational since 2000
Current System • Records up to twenty channels on five PCs • Content from around the world • More than half of these channels have EPG • US and Canadian channels have captions • Operates at a house in suburban MD
Current System Issues • Analog based • Recodes video that comes in digital • Caption data is lost in recordings (kept as text) • Expensive to expand • A big chunk stops working in February 2009!
Digital Future • The future of broadcasting is digital • One big lesson learned: • Needs to be geographically redundant • …and therefore inexpensively implemented • …and inexpensive to run long term
MPEG-2 Transport Stream • The worldwide standard for broadcast DTV • A single analog channel is replaced with a digital multiplex • The multiplex can contain one or more programs • Encoded with different codecs • With multiple audio and data streams
Digital Archiving • Splits programs from MPEG-2 transport streams • One tuner required per multiplex • Multiplex may contain a number of useful programs or just one • Transparent across the world’s DTV standards • Works with terrestrial, satellite and cable
Digital Archiving • Splits files based on EPG or a timer • EPG from in or outside the multiplex • Extracts captions in North America • Extracts subtitles in some European countries • Generates thumbnail pictures of video • Automatically moves data onto empty drives • XML index to each event recorded
Hardware is cheap! • For two channel terrestrial: • PC - $400 • Monitor - $150 • Two off-air DVB-T or ATSC cards - $200 • UPS - $200 • Antenna - $50 • Around $1000 per system
Storage is cheap! • 1 TB SATA drives are now typically $179 • With MPEG-2 SD, that’s 23 days • …or 46 days with H.264 SD • …and 6 days MPEG-2 HD • About $8 per channel per MPEG-2 SD day • Two MPEG-2 SD per year for less than $7000
Digital Archiving Examples • Multiplexes from around the world
Broadcast Television Archiving Rod Hewitt rod@coolstf.com