Ad Insertion Takes Second Step11/04/2001 7:00 PM Eastern
The push to insert local advertising on digital channels passed a second hurdle last week, as Cable Television Laboratories Inc. and a Society for Cable Telecommunications Engineers working group successfully offered up a live demonstration of working digital program insertion technology from eight vendors.
"We're working on a end-to-end system to replace the analog systems of today," said CableLabs executive vice president and chief operating officer Chris Lammers.
The Oct. 29 demonstration at CableLabs was about "making sure the equipment works together in the pre-commercial stage," Lammers said.
Scientific-Atlanta Inc., Motorola Inc., Cisco Systems Corp.'s V-Bits division, Terayon Communication Systems Inc.'s I-Media CherryPicker, Harmonic Inc., nCUBE Corp., Big Band Networks and SeaChange International Inc. participated in a demonstration that addresses a host of digital ad-insertion issues.
The development of digital program insertion is important for two reasons. Firstly, cable operators are looking for ways to create local avails on digital networks without going through costly digital-to-analog-to-digital conversions.
Some operators also believe they'll move to all-digital networks once digital penetration hits a certain level. In both cases, a seamless, cost-efficient digital ad-insertion system is needed.
Last week's round of testing is grew out of the DVS 253 cue messaging and DVS380 application-program interface standard developed by the Digital Video Subcommittee Working Group of the Society of Cable Telecommunications Engineers, chaired by Adlink chief technology officer Paul Woidke. Those standards were established this summer.
Last week's demonstration showed off working prototypes of end-to-end solutions that MSOs will likely test in their own labs in 2002.
CableLabs and the SCTE working group will reconvene for another series of final demonstrations of the technology next year. Vendors hope that paves the way for MSOs to buy digital program insertion systems in 2003.
One demonstration centered on variable bitrate streams from four cable networks. They were statistically multiplexed together, then the feeds were presented to a slicing device, which inserted the commercials into the feeds for transmission over a digital network. Bit rates were set between 3 and 6 mbps with 30- and 60-second commercials.
The TV monitors in the demonstration utilized the DVS380 standard, triggered by the embedded DVS253 messages.
A second demonstration showed how splicers can be cascaded and controlled by multiple ad servers for the same inserted network. That setup would allow operators to send different ads to separate regions within their cable systems.
A third demonstration centered on handling changes in the audio bitrate, such a network feed that's encoded at 128 Kbps which carries an advertisement encoded at 384 Kbps.
Other demonstrations focused on dual audio feeds, changes in horizontal resolution and the early termination of advertisements.
ESPN also demonstrated digital ad insertion using a live satellite feed of ESPN2, carried in the edge band of the 36 mHz analog signal.