VIVOTEK
User's Manual - 67
■ 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
A complex scene generally produces a larger le size, meaning that higher bandwidth will be needed
for data transmission. Therefore, if Constant bit rate is selected, the bandwidth utilization is xed at
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.
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.
If JPEG mode is selected, the Network Camera continuously sends JPEG images to the client, producing
a moving effect similar to a filmstrip. Every single JPEG image transmitted guarantees the same
image quality, which in turn comes at the expense of variable bandwidth usage. Because the media
contents are a combination of JPEG images, no audio data is transmitted to the client. There are three
parameters provided in MJPEG mode to control the video performance:
■ Frame size
You can set up different video resolution for different viewing devices. For example, set a smaller
frame size and lower bit rate for remote viewing on mobile phones and a larger video size and a higher
bit rate for live viewing on web browsers. Note that a larger frame size takes up more bandwidth.
■ Maximum frame rate
This limits the maximum refresh frame rate per second. Set the frame rate higher for smoother video
quality.
If the power line frequency is set to 50Hz, the frame rates are selectable at 1fps, 2fps, 3fps, 5fps,
8fps, 10fps, 15fps, 20fps, and 25fps. If the power line frequency is set to 60Hz, the frame rates are
selectable at 1fps, 2fps, 3fps, 5fps, 8fps, 10fps, 15fps, 20fps, 25fps, and 30fps. You can also select
Customize and manually enter a value. The frame rate will decrease if you select a higher resolution.
■ Video quality
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.
NOTE
►
Video quality and fixed quality refers to the compression rate, so a lower value will produce higher
quality.
►
Converting high-quality video may significantly increase the CPU loading, and you may encounter
streaming disconnection or video loss while capturing a complicated scene. In the event of occurance,
we suggest you customize a lower video resolution or reduce the frame rate to obtain smooth video.