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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.
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MPEG4 ASP(Advanced Simple Profile):
Its notable technical features relative to the Simple Profile, which is roughly similar to H.263,
including "MPEG"-style quantization, interlaced video, B pictures (also known as B Frames), Quarter
Pixel motion compensation (Qpel), Global motion compensation (GMC).
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Resolution:
It 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 1920x1080, 1280x1024,
1280x720, 704x480(576), 640x480, 352x240(288), and 320x240. Users can reset the selected
screen size anytime while monitoring the screen on a real-time basis.
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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.
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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.
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GOP size:
Select the GOP(Group of Picture) size. If users want to have a high quality of fast image one by one,
please decrease the value. For the purpose of general monitoring, please do not change a basic
value. Such act may cause a problem to the system performance. For the details of GOP setting,
please contact the service center.
• Stream2 Setting
Sometimes the image size is large due to low light or complex scenery. Adjusting the frame rate and
quality helps to control the bandwidth and storage used by the Motion JPEG video stream in these
situations. Limiting the frame rate and quality optimizes bandwidth and storage usage, but may give poor
image quality. To prevent increased bandwidth and storage usage, the Resolution, Frame rate, and
Frame Quality should be set to an optimal value.
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JPEG resolution:
Same as the Stream1 Setting.
