RADVision Scopia XT1000, Test Results

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1080p 30fps.
The main video channel allows selection of either HDMI input or the single DVI
signal but only the DVI input may be selected on the H.239 second video channel;
thus if two camera images are to be transmitted simultaneously the second camera
must be connected to the DVI input.
When presentation material is transmitted the resolution and frame rate of the main
and second video channels depends on the connection bandwidth and the nature of
the material. The system protects the resolution of the presentation channel at 1080p
but reduces the resolution of the main video channel and the frame rate of both
channels as connection bandwidth is reduced. The following table illustrates this:
Connection
Bandwidth
Without
Presentation With
Presentation
Main Channel Main Channel Presentation
4M bit/s 1080p 1080p 1080p
2M bit/s 1080p 720p 1080p
1M bit/s 720p w576p 1080p
768 kbit/s 720p w448p 1080p
384 kbit/s w448p w228p 1080p
128 kbit/s w224p w224p 1080p
Several audio formats are supported by the SCOPIA XT1000. Radvision has
implemented the ITU standard G.719, giving 20Hz-20KHz analogue audio with
low latency/delay. The 3-way microphone pod uses beam forming technology to
improve pickup from the presenters while minimising background noise. In larger
installations an additional microphone pod may be daisychain cabled to the main
microphone. A microphone mute button with LED mute indication mutes not only
the microphone but all other audio transmitted from the CODEC including the
SPDIF audio input.
Digital stereo connectivity is provided via SPDIF input and output connectors.
If analogue DVD, PC audio or public address systems are being used then suitable
Analogue to Digital (A–D) converters will be required. Radvision specifies that the
SPDIF input can accept stereo signals at 32, 44.1 and 48KHz bit rates, and
recommends the Cypress conversion device; however Lindy A-D converters were
supplied with the CODECs for evaluation and although rated at 48KHz they
produced a choppy rather distorted audio signal. A Marantz recorder equipped with
a digital SPDIF output at 44.1 KHz operated effectively. Care is therefore required
in the selection of A-D convertors.
The CODEC‟s main audio output is also delivered on the main HDMI output.
Encryption is available at all connection speeds through Advanced Encryption
Standard (AES).