Grass Valley PROFILE FAMILY v.2.5 - Manual (Page 24)

Chapter 1 Introducing the Profile Family
24 Profile Family
A Profile System Overview
The PDRseries of video servers are multichannel digital disk recorders. Both
the PDR100 and PDR200 are capable of supporting up to four play/record
channels (codecs) of continuously variable motion JPEG video compression.
The PDR200 and PDR 300 support Fibre Channel networking and MPEG
4:2:0/4:2:2 video compression, with up to two record channels (encoders) and
up to eight playback channels (decoders). Each channel can play back one video
and up to 16 audio signals, each capable of using different video formats. In
other words, one Profile unit can replace the functionality of up to eight VTRs,
with the added benefit of random access to video and audio data stored on disk.
The Profile system has an EISA motherboard with an internal digital video
routing system. There are sixteen EISA slots and one ISA slot used for interface
cards and routing audio data. The server also uses a PCI bus for routing data
between the master and slave enhanced disk recorder (EDR) boards, Fibre
Channel boards, and MPEG boards.
A video router chip set is integrated on the mother board. It routes video signals
between the video disk system, video mix effects cards, and video I/O cards.
The video router is a 32 x 32 crosspoint matrix capable of full bandwidth 4:2:2
CCIR 601 8-bit digital video. The video router allows real-time transfer of
video throughout the system without impacting overall system performance.
The video router also makes possible simultaneous record and playback on
separate channels.
A block diagram showing the hardware layout of a PDR200 or above is shown
in Figure 1 on page 27.
Video Disk Subsystem
In the video disk subsystem, video data is compressed and written to up to eight
4-gigabyte (PDR100 only) or 9-gigabyte disks, and then read from these disks
and decompressed. This video data is read from and written to the video router
in 8-bit, parallel component digital video format. The video disk subsystem has
disk recorder boards (PDR100) and enhanced disk recorder boards (PDR200
and above), with an Intel i960 real-time processor and a SCSI-2 interface to the
disks.
The video disk subsystem uses master and slave disk recorder or enhanced disk
recorder (EDR) boards with two SCSI-2 channels on each board. The master
disk recorder board comes standard with a two-channel JPEG codec.
Bidirectional codec channels allow channels to be configured for recording or