DVD-RAM Cam Debuts

Hitachi recorder docks to Z-3000 series camera

The next buzz in recording officially arrived on the market last week. Hitachi Denshi's DVD-RAM recording unit, which docks to the company's Z-3000 series camera, hit the street.

The recorder, introduced at NAB this year, is the first DVD-based unit to hit the professional market, but it definitely won't be the last. The next year promises to be a busy one, with DVD—and disk-based recording—on the verge of release by a number of manufacturers.

"The whole idea is to make recording faster, easier and more dependable," says Emilio Aleman, Hitachi Denshi product manager.

Hitachi is the first to implement the DVD-RAM recording format for the professional market, with DVD-RAM and DVD-Rs capable of storing 4.7 Gb of information (each disk costs roughly $20). Maximum recording bit rate is 9 Mb/s, which gives users up to 30 minutes of recording on each side of the disk. At a 3-Mb/s rate, recording can reach 60 minutes per side.

The format uses MPEG-2 variable-bit-rate recording, with long-GOP IDP frames. Aleman says that allows more-efficient recording than recording based on I-frames or DCT only. Unfortunately, it also prevents apples-to-apples comparison against formats like DVCPRO or DVCAM based strictly on the numbers. Most broadcasters look to 25-Mb/s or 50-Mb/s DVCPRO and DV-CAM as a baseline—and 9 Mb/s is well below that floor.

"The benchmark is, the higher the bit rate, the better the video is going to look," says Aleman, "but what is the encoding and compression scheme?"

Aleman says that, in demos he has given, most of the viewers have guessed the bit rate at 15 to 18 Mb/s, something he believes speaks to the quality of the recording.

The transport can currently download content into nonlinear editing systems at 22 Mb/s, or roughly two times real time. Work is already under way on the next generation, with the goal to get transfer speeds up to six or eight times real time. But that next-generation technology probably won't be seen until NAB 2004. One thing that should be seen at NAB next year is a one-piece camcorder unit based on half-inch CCD technology.

Aleman says Hitachi is in discussion with manufacturers of nonlinear editing systems to ensure that the systems can easily use content from the drives. Adobe Premiere can already work with the recorder, and others in on the discussions include Avid, Leitch, Apple and Pinnacle.

Aleman says most nonlinear editors can decode MPEG-2 transport streams. And what DVD-RAM offers is a file structure that allows the nonlinear editor to recognize the file clips off the disk.

"Right now, users in the field are able to create the clip and view icons that represent all the clips on the disk," says Aleman. "They can even label the clips and create a playlist. And when they get back to the editing environment, they can download that playlist right into the editing bin."