VIVOTEK
42 - User's Manual
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Video quality
•
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, and 8Mbps
. 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 40Mbps. 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. This can ensure bandwidth is not
exhausted when extra-high bit rate is accidentally produced, e.g., lots of noises in a video
taken by the night time.
You may also manually enter a bit rate number by selecting the
Customized
option.
