Sony SRW-5500 VCR User Manual


 
9
1-1 Features
Chapter
Chapter 1 Overview
1
Overview
1-1 Features
1-1-1 Features of the SRW-5000/
SRW-5500
The SRW-5000/SRW-5500 is a high-definition digital
videocassette recorder using the HDCAM-SR format. It is
a small and light unit incorporating LSIs for signal
processing and is comparable to the HDCAM
1)
model
HDW-F500 in size, weight and functionality.
The SRW-5500 only is a recorder supporting both the
HDCAM-SR and HDCAM formats.
1) HDCAM is a trademark of Sony Corporation.
HDCAM-SR format
The HDCAM-SR format exploits technological advances
in signal processing and magnetic recording, to provide
functionality comparable to that of the HDCAM format,
while offering HD digital recording and playback with
high image and sound quality.
The technology incorporated in this unit includes the
following.
Highly efficient and mild data compression using newly
developed MPEG-4 Studio Profile
Powerful error-correcting codes
High-performance, high-accuracy heads and drum with
dynamic tracking (DT ™), together with a new auto-
tracking technique, yielding highly reliable narrow track
recording and playback.
These technologies allow 120 minutes of recording on an
HDCAM-SR cassette (L type), the same size as the
HDCAM cassette.
Digital signal processing
In this unit, 4:2:2 component video signals obtained by
quantization according to ITU-R709, SMPTE 274M and
BTA S-002B (SMPTE 260M) are compressed using
MPEG-4 Studio Profile. Audio signals are processed
uncompressed, according to the AES/EBU format.
Input interface
The input interface is based on the HD SDI (HD Serial
Digital Interface) format specified by BTA S-004B/005B/
006B (SMPTE 291M/292M/299M) and ARIB STD-B4,
allowing a single BNC coaxial cable to carry one
component video signal, twelve digital audio channels,
and time code in time division multiplex; this is separated
for conversion to parallel data.
Audio recording can be switched between the digital audio
signal multiplexed with the HD SDI signal and the audio
signal from an AES/EBU digital interface.
Bit rate reduction encoder
The component video signal undergoes frame shuffling. It
is then compressed by a process in which it is subjected to
DCT (discrete cosine transform) or DPCM (differential
pulse code modulation), quantization control, and variable
length word encoding. This is the core of the newly
developed MPEG-4 Studio Profile. Interlaced signals are
compressed in fields and progressive signals are
compressed in frames.
ECC encoder
The outer ECC (Error Correction Code) is added to the
compressed video and audio data, followed by the inner
ECC, ID data, and sync data. Reed-Solomon codes are
employed in this error correction system.
Channel coding
Video and audio data with the ECC added is recorded in
the form of serial data. The HDCAM-SR format adopts a
scrambled i-NRZ channel coding system, giving
consideration to off-track and noise characteristics.
Playback signal processing
The playback digital signal is equalized by an equalizer
circuit. It then passes powerful inner and outer ECCs
which can correct dropouts in the reproduced signal. It
further goes through an error concealment circuit to have
errors still remaining in the signal rectified.
Output interface
Component video data is converted into serial data and
multiplexed with audio data and time code, then output in
the HD SDI format.