Vivotek IP8152 User Manual page 54

VIVOTEK
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:
Target bit rate:
A complex scene generally produces a larger file size, meaning that higher bandwidth
will be needed for data transmission. To regulate the bandwidth consumption and
storage space for recording videos, you can select the Constant bit rate methodology.
The firmware will try its best to contain the size of video packets within the limitation
of a constant bit rate. This methodoloy enables easier calculation of the network
bandwidth and storage space required for live viewing or video recording.
Policy:
- Frame rate priority - Firmware will try to maintain the target frame rate per second,
while the image quality will more or less be compromised.
- Image quality priority - Firmware will try to maintain the quality of the video while the
frame rate (no. of frames per second) may decrease.
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.
• Fixed quality: On the other hand, if Fixed quality is selected, all frames are
transmitted with the same quality; bandwidth utilization is therefore unpredictable.
When so configured, the frame-rate-per-second performance can be compromised
in the event of insufficient bandwidth or network clogs. The video quality can be
adjusted to the following settings: Medium, Standard, Good, Detailed, and Excellent.
You can also select Customize and enter a number to designate image quality. The
larger the number, the higher the compression rate, and hence image quality is lower.
A small customized quality number means a low compression rate, and a high quality
image.
- Maximum bit rate - While you want to ensure a reasonable image quality, you can
still impose an upper threshold on the bandwidth taken for the video transmission.
The configurable bit rate ranges from 1mbps to 40mbps.
54 - User's Manual