Broadcast Collection
LDC has developed and maintains an extensive system for collecting broadcast content from satellite, cable TV, and off-the-air television and radio.
The satellite reception facilities can address up to five simultaneous C/Ku-Band satellite downlinks. These feeds are used for DVB-S/S2 free-to-air and conditional access programming from the Galaxy-19 and Galaxy IIIC satellites. The system includes 26 DVB-S/S2 receiver decoders, including two dedicated SCOLA receivers.
The terrestrial reception component of the collection system includes two ATSC receivers, six CATV demodulators, and two radio receivers, all of which are computer controllable. These receivers are dedicated to English and Spanish programming from the Southeastern Pennsylvania broadcast region.
The array of signal reception equipment feeds a computer-controllable 256x64 audio/video matrix switch that routes content from any receiver to video monitors, closed caption decoders and the recording node cluster.
The recording node cluster contains twelve dual stream collection nodes and four quad transponder collection nodes. Each dual stream collection node is capable of recording two simultaneous Audio/Video/Closed-Captions streams, and has an internal capacity of 240 hours. Audio/Video are captured as DV25, and closed captions are captured using an EIA-608/708 decoder. Each transponder collection node is equipped with two dual decoder DekTec DTA-2137 receivers, allowing for the capturing four simultaneous DVB-S/S2 transponders per node. The original MPEG-2 Transport Stream from each transponder is captured directly to disk; individual channels are then extracted from the transport stream. All channels are transcoded to H.264/MPEG-4. In total, the cluster can process up to 24 simultaneous A/V/C streams and 16 transponder streams per day. The upper limit of content which can be captured per day is 1000 hours.
A supervisor computer with a customized scheduling database drives all collection activity, controlling receivers, audio video matrix routing and recording jobs. The system also incorporates 24TB of local storage, dedicated automatic speech recognition and multimedia transcoding systems, a 24TB LTO4 tape backup system, and an eight node transcoding cluster for high volume bulk transcoding jobs. The broadcast collection system is highly modular, highly reliable and fully automatic.
LDC has also developed and deployed two portable broadcast collection platforms outside the United States. Each is a digital video recording system capable of recording two simultaneous streams. The platforms include integrated DVB-C, analog CATV, and DVB-S/S2 satellite reception components. They are designed to support a wide range of international broadcast standards.
The portable platforms and the main LDC collection systems share the same code base and rely on a modular, unified hardware specification. Improvements in the main collection platform translate into benefits for the portable platforms as well. All collection nodes run Ubuntu Linux and use DekTek, Hauppauge, Technotrend, and Tenow receiver/decoders. The data capture software is built upon the Linux Media Infrastructure API.