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The HDCAM-SR format is based on cutting-edge technology. It is not a rehashed and repackaged technology solution developed in
previous decades. The HDCAM-SR format has been designed to maximize the data-transfer rate without sacrificing any operational
features. It’s a design you’d expect from a Sony 1/2” tape format, with all the useful playback and editing features common to
existing Sony tape formats. And although the SRW-5000 features and capabilities have seen great improvements, the physical size
and power consumption of the VTR remain modest enough to achieve easy portability for field use. And, in order to meet the
format’s mission-critical requirements, every aspect of magnetic tape-recording engineering and digital-signal processing technology
has been carefully reassessed and integrated. Even with these great technological improvements, the expected operating costs of this
system are reasonable.
Creating Virtually Lossless Images:
The MPEG-4 Studio Profile (SP)
Yet another industry first from Sony is an integrated video
encoding/decoding chipset that conforms to the MPEG-4 SP
(Studio Profile: ISO/IEC 14496-2:2001-1). The Studio Profile
was created to specifically address the requirements of
high-resolution image-production applications. It is free from
GOP (Group Of Pictures) structures, and is scalable in its pixel
count (SDTV, HDTV, Film-resolution data), bit depth (10- or
12-bit), and color resolution (component or RGB). In order to
achieve maximum compression efficiency, the HDCAM-SR
format resorts to intra-frame compression for progressive
images. Intra-field compression is used for interlaced images.
Special attention has been paid to multi-generation dubbing
performance and, in common with industry-standard Digital
BETACAM VTRs, the SRW-5000 is capable of consistent
dubbing without using a separate interface for a native stream.
This is only possible thanks to the high performance of the
MPEG-4 SP, which offers reproduction of virtually lossless
images.
More Data, Same Long Running Time:
The New Footprint
Each picture frame consists of 24 helical tracks (or 12 tracks
per segment/field), in which data is shuffled to protect the
recording from occasional burst errors. Recordings are further
protected by highly robust error-correction and concealment
techniques perfected through years of Sony digital-VTR
development. Thanks to the finer track pitch and shorter
minimum recording wavelength, the data-packing density of
the HDCAM-SR format is 3.5 times that of the HDCAM
format. Frame-accurate editing is guaranteed by the intelligent
allocation of pilot signals for precise head-to-tape tracking.
Technology – A Behind The Scenes Look