Post It In Dolby E For DTV

Getting multichannel audio to the DTV transmitter isn't easy, because few TV broadcast and distribution facilities are equipped to handle more than two channels. So that they won't have to rip out their audio infrastructure and start over for multichannel audio, Dolby Laboratories has developed Dolby E. Dolby E is a new digital audio coding that enables a single AES digital audio pair to carry up to eight audio channels plus Dolby Digital metadata, making it possible for most existing digital audio equipment, including digital VTRs, servers, and routing switchers, to handle multichannel programming.An Ideal Distribution SystemUnlike Dolby Digital audio coding, which is ideal for transmitting multichannel audio to consumers but not for distribution purposes, Dolby E can provide, without degradation, up to the ten generations required during the contribution, post-production, and distribution stages of a DTV program. Dolby E audio data is synchronized with the accompanying video, making glitch-free edits on tape and audio-follow-video cuts between programs possible. In addition to consumer metadata that is ultimately transmitted to the viewer via the Dolby Digital broadcast signal, Dolby E carries professional metadata that can be used by the broadcaster to re-synchronize, monitor, and modify the level of the decoded audio. Thanks to Dolby E, post facilities can now deliver finished multichannel programs via current digital VTR formats. On a tape with four audio tracks, for example, one pair encoded with Dolby E can carry both 5.1-channel and Dolby Surround Lt/Rt mixes of the program. The second pair can carry a PCM stereo or Dolby Surround Lt/Rt mix optimized for NTSC or PAL analog transmission, for broadcast stations without DTV service.