MediaPort I/O Components
MediaPorts are the physical I/O devices used to input or output media to an Omneon server. Each
MediaPort is responsible for a single channel, and processes video, audio and timecode. They are all bi-directional, offering record or playback capability (though not
simultaneously – a MediaPort is either in record mode, or play mode at any one point in time).
This
is an important architectural point – since MediaPorts are bi-directional, they can be used to record
material, then reconfigured via software to play that same material out, which minimizes the
number of MediaPorts needed for any application. There are multiple variants of MediaPorts, three
of which deal with input and output of baseband (serial digital) video (including VITC), AES audio (if
required), and LTC. All 3 take in this baseband media and compress it into either DV or MPEG2
files, which are then sent to the MediaServer for storage. The difference in these MediaPorts merely
defines the kind of MPEG2 files encoded – Iframe only, Iframe and Long GOP, or Iframe/Long
GOP/IMX. All 3 can play back all DV and MPEG2 types, so the decision on which a customer should
use is purely dependent on the record format.
Another MediaPort variant is also capable of inputting serial digital video, but passes this down on
to the MediaServer uncompressed, yielding the highest possible picture quality. This MediaPort is
also capable of inputting video over SDTI (Serial Data Transport Interface). Currently, this is the
method used to input DV or DVCPRO material at faster than real time, to input High Definition
material compressed in HDCAM format, or to input High Definition material compressed in DVCPRO
HD format. |