November 14, 2002
Hitachi Denshi America: DVD-RAM Recording Technology
With the advent of DVD-RAM recording technology and its proliferation in consumer video editing and authoring, the DVD is poised to gain acceptance with professional users wishing to eliminate the traditional drawbacks of videotape. The inherent nonlinear access of audio and video makes DVD-RAM recording technology a strong contender in the content acquisition marketplace.
The concept of having a content ingestion system that complements the fundamental functions of modern nonlinear editors is the key driving force behind the implementation of DVD-RAM recording in professional video cameras. Prior to this, other camera manufacturers tried to implement the same with the use of compact hard disc technology. To some extent, they had success with this, but were plagued by the high cost of the removable medium÷the hard disc drive. Although the cost of storage has declined dramatically in the past few years, the dollar-to-megabyte ratio still does not come close to videotape storage, whereas the DVD-RAM disc is expected to surpass it.
Since the actual DVD-RAM v2.1/DVD-R v2.0 media has a fixed storage value (4.7Gb/side, 8-cm, Type-2 discs), the recording time per disc is defined by the MPEG-2 video encoding rate and method employed. The Hitachi CR-D10 offers two encoding rates as well as a variable bit rate encoding mode.
In the development of our new dockable recorder model CR-D10 and one-piece 3-CCD camera recorder model C-D10, Hitachi has paid particular attention to the drives' ruggedness and reliability, as required by broadcast and professional users. Electro-mechanical disc stabilization systems have been implemented in order to guarantee flawless audio and video recording performance. Benefits of Hitachi's DVD-RAM technology include:
* Nonlinear access to audio and video recorded on low-cost, stable, and rugged media. The DVD-RAM disc can be reused up to 100,000 times.
* Simplification of the electro-mechanical device. The disc drive requires much less maintenance and is more stable than videotape recorders.
* Recording method is an industry-wide standard and compatible with other drives/recorders to be manufactured by other companies.
* Compatibility with popular NLEs that process MPEG-2 files and read directly from the DVD-RAM discs' UDF file format.
* Possible faster-than-realtime digital-to-digital transfers into NLEs and file servers with the use of Hitachi DVD-RAM library systems and SANs.
* Field transmissions/uploads with the use of laptop PCs via TCP/IP through a digital interface on a recorder and camcorder.
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