Vicon Series 247-00-03, User Manual

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* H.264 MP (Main Profile):
Primarily for low-cost applications that require additional error robustness, this profile is
rarely used in videoconferencing and mobile applications; it does add additional error
resilience tools to the Constrained Baseline Profile. The importance of this profile is fading
after the Constrained Baseline Profile has been defined.
* H.264 BP (Base Profile):
Originally intended as the mainstream consumer profile for broadcast and storage
applications, the importance of this profile faded when the High Profile was developed for
those applications.
* MPEG4 SP (Simple Profile):
Mostly aimed for use in situations where low bit rate and low resolution are mandated by
other conditions of the applications, like network bandwidth, device size etc.
* MPEG4 ASP (Advanced Simple Profile):
Its notable technical features relative to the Simple Profile, which is roughly similar to H.263,
include "MPEG"-style quantization, interlaced video, B pictures (also known as B Frames),
Quarter Pixel motion compensation (Qpel), and Global motion compensation (GMC).
- Resolution:
Enables users to determine a basic screen size when having an access through the Web
Browser or PC program. The screen size control comes in seven modes like 640x480,
352x240(288), and 320x240. Users can reset the selected screen size anytime while
monitoring the screen on a real-time basis.
- Bitrate control:
Limiting the maximum bit rate helps control the bandwidth used by the H.264 or MPEG-4
video stream. Leaving the Maximum bit rate as unlimited maintains consistently good image
quality but increases bandwidth usage when there is more activity in the image. Limiting the
bit rate to a defined value prevents excessive bandwidth usage, but images are lost when
the limit is exceeded.
Note that the maximum bit rate can be used for both variable and constant bit rates.
The bit rate can be set as Variable Bit Rate (VBR) or Constant Bit Rate (CBR). VBR adjusts
the bit rate according to the image complexity, using up bandwidth for increased activity in
the image, and less for lower activity in the monitored area.
CBR allows you to set a fixed target bitrate that consumes a predictable amount of
bandwidth. As the bit rate would usually need to increase for increased image activity (but in
this case cannot), the frame rate and image quality are affected negatively. To partly
compensate for this, it is possible to prioritize either the frame rate or the image quality
whenever the bit rate needs to be increased. Not setting a priority means the frame rate and
image quality are equally affected.
- Frame rate:
Upon the real-time play, users should select a frame refresh rate per second. If the rate is
high, the image will become smooth. On the other hand, if the rate is low, the image will not
be natural but it can reduce a network load.