VIVOTEK
72 - User's Manual
The frame rate will decrease if you select a higher resolution�
■ Intra frame period
Determine how often to plant an I frame� The shorter the duration, the more likely you will get
better video quality, but at the cost of higher network bandwidth consumption� Select the intra
frame period from the following durations: 1/4 second, 1/2 second, 1 second, 2 seconds, 3
seconds, and 4 seconds�
■
Video quality
Constant bit rate:
•
Constant bit rate
:
A complex scene generally produces a larger file size, meaning
that higher bandwidth will be needed for data transmission� The bandwidth
utilization is configurable to match a selected level, resulting in mutable video quality
performance. The bit rates are selectable at the following rates: 20Kbps, 30Kbps,
40Kbps, 50Kbps, 64Kbps, 128Kbps, 256Kbps, 512Kbps, 768Kbps, 1Mbps, 2Mbps,
3Mbps, 4Mbps, 6Mbps, 8Mbps, 10Mbps, 12Mbps, 14Mbps, and 16Mbps� You can
also select
Customize
and manually enter a value�
- Target bit rate
: select a bit rate from the pull-down menu. The bit rate ranges from
20kbps to a maximum of 8Mbps� The bit rate then becomes the Average or Upper
bound bit rate number� The Network Camera will strive to deliver video streams
around or within the bit rate limitation you impose�
- Policy:
If Frame Rate Priority is selected, the Network Camera will try to maintain
the frame rate per second performance, while the image quality will be compromised�
If Image quality priority is selected, the Network Camera may drop some video
frames in order to maintain image quality�
• Fixed quality:
On the other hand, if
Fixed quality
is selected, all frames are
transmitted with the same quality; bandwidth utilization is therefore unpredictable�
The video quality can be adjusted to the following settings: Medium, Standard, Good,
Detailed, and Excellent� You can also select
Customize
and manually enter a value�
- Maximum bit rate:
With the guaranteed image quality, you might still want to place
a bit rate limitation to control the size of video streams for bandwidth and storage
concerns. The configurable bit rate starts from 1Mbps to 40Mbps.
The Maximum bit rate setting in the Fixed quality configuration can ensure a
reasonable and limited use of network bandwidth� For example, in low light conditions
where a Fixed quality setting is applied, video packet sizes can tremendously
increase when noises are produced with electrical gain�
You may also manually enter a bit rate number by selecting the
Customized
option�
