User's Manual
Chapter 2 - Technical Information
© Polycom, Inc. 15
The following table gives electrical specifications for the video 
inputs and outputs.
The following table gives other video specifications for the 
ViewStation EX, ViewStation FX, and VS4000 systems.
Table 2-5. Video Input/Output Electrical Specifications
Parameter Value/format
Impedance 75 Ω
Signal amplitude 1.0 V
pp
 typical
Coupling DC
Table 2-6. Video Resolution, Frame Rate, and Error Correction
Parameter Value/format
Video format NTSC or PAL
Video resolutions QCIF (176 x 144)
CIF (352 x 288)
4CIF (704 x 576)
TV-quality wide-screen (letterbox)
Graphics 
resolutions, slide 
transmission
H.261 mode: 4CIF (704 x 576)
H.263 mode: 16CIF (1408 x 1152)
Graphics resolution, 
local display
up to 1280 x 1024
Frame rate  NTSC: 30 frames/second 
(60 fields/second)
PAL: 25 frames/second (50 fields/second)
Error correction Polycom Video Error Concealment (PVEC)
a
a. PVEC is activated and deactivated automatically, as needed. 
Video quality degradation with the PVEC feature active may 
indicate that your IP network is not functioning properly. At the time 
of publication, PVEC is not available in dual stream mode or 
standards-based 60-field video.










