Snell & Wilcox MEMPHIS system heads to WXIA Atlanta
Gannett-owned NBC affiliate WXIA-TV Atlanta, GA is using a Snell & Wilcox MEMPHIS encoder to ingest uncompressed HD content and enable file-based storage and flexible delivery of that content over its SD and HD broadcast channels.
The MEMPHIS encoder serves as a platform for real-time processing of HD-SDI signals, which are output as ASI streams onto the facility’s Omneon Spectrum media server system for storage and subsequent playout in the appropriate format for each channel.
“We selected the MEMPHIS encoder from Snell & Wilcox not only for its superior MPEG-2 processing technologies, but also because of the respect it has earned from other key vendors involved in our new HD-capable technical operations center,” said Lenard Thomas, chief engineer at WXIA-TV. “The MEMPHIS is clearly the industry’s product of choice for integration with HD server systems.”
The MEMPHIS encoder incorporates two Emmy Award-winning technologies to provide superior image quality at lower bit rates. Snell & Wilcox Ph.C phase correlation motion estimation technology and Prefix compression preprocessing together enable compression efficiency while also reducing noise and fine-tuning images to achieve an unusually sharp and crisp picture quality. Both the MEMPHIS and Omneon Spectrum systems support common SMPTE specifications, and their high level of interoperability enables WXIA-TV to maintain frame-accurate time codes, proper mapping of PCM and Dolby E to maintain audio phase, and full surround-sound capability.
WXIA-TV is feeding uncompressed HD signals into the MEMPHIS system, which creates a high-quality MPEG-2 signal and places it within an ASI transport stream. The ASI stream is then passed to the Omneon Spectrum, where the MPEG-2 material is de-multiplexed and stored as a file-based asset and when required by a playout schedule, the HD clip is retrieved from storage and decompressed to create an uncompressed HD signal. This HD clip is simultaneously downconverted to provide an SD feed for playout. The SD signal broadcast by WXIA-TV is devoted to NBC’s Weather Plus, a digital weather channel, and the primary program stream is output via an analog channel and a digital channel that offers HD wherever possible.
“Every piece of Snell & Wilcox we’ve ever used has performed well, and the MEMPHIS has been no exception,” added Thomas. “The support we received from Snell & Wilcox during the integration and installation was very impressive, and once the MEMPHIS encoder was configured, it operated smoothly, providing reliable day-to-day operation without the need for any adjustment.”