VIVOTEK - A Leading Provider of Multimedia Communication Solutions
User's Manual - 39
If MPEG-4 mode is selected, it is streamed in RTSP protocol� There are four dependent parameters
provided in MPEG-4 mode for video performance adjustment�
■ Frame size
Select the video size� Note that a larger frame size takes up more bandwidth� The frame sizes are
selectable in the following resolutions: 176 x 144, 352 x 240, and 640 x 480�
■ Maximum frame rate
This limits the maximal refresh frame rate per second� Set the frame rate higher for a smoother video
quality�
If the power line frequency is set to 50Hz, the frame rates are selectable at the following rates: 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 the following rates: 1fps, 2fps, 3fps, 5fps, 8fps, 10fps, 15fps, 20fps,
25fps, and 30fps�
■ Intra frame period
Determine how often to plant an I frame� The shorter the duration, the more likely you will get a
better video quality, but at the cost of higher network bandwidth consumption� Select the intra frame
period from the following duration: 1/4 second, 1/2 second, 1 second, 2 seconds, 3 seconds, and 4
seconds�
■ Video quality
A complex scene generally produces 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 performances� The bit rates are selectable at the
following rates: 20Kbps, 30Kbps, 40Kbps, 50Kbps, 64Kbps, 128Kbps, 256Kbps, 512Kbps, 768Kbps,
1Mbps, 1�5Mbps, 2Mbps, 3Mbps, and 4Mbps�
On the other hand, if Fixed quality is selected, all frames are transmitted with the same quality;
bandwidth utilization is therefore unpredictable� The video qualities are selectable at the following
settings: Medium, Standard, Good, Detailed, and Excellent�
If JPEG mode is selected, the Network Camera continuously sends JPEG images to the clients,
producing dynamic effects similar to movies� Every single JPEG image transmitted guarantees the
same image quality, which in turn comes at the expense of variable bandwidth usage� And because
the media contents are a combination of JPEG images, no audio data is transmitted to the clients�
■ Frame size
Select the video size� Note that a larger frame size takes up more bandwidth� The frame sizes are
selectable in the following resolutions: 176 x 144, 352 x 240, and 640 x 480�
