Grandstream Networks HandyTone HT286 Product Related Questions page 15

call. This is very useful in an enclosed LAN environment where you can assign static IP based
on, for example, room number in a building.
Q: How do I set up the video phone when my internet bandwidth connection is very low?
You need at least 128kbps bandwidth in both directions (uplink and downlink) to make the
GXV-3000 work with good picture quality.
If using less than 128kbps, for example 96kbps bandwidth, you can configure: Frame Rate to 5
(lowest) and Video Bit Rate to 64kbps or even 32kbps (lowest), to see if the video quality is
acceptable in your network environment. Otherwise, please upgrade your bandwidth as you don't
have enough physical data pipe to run the video data stream.
Detailed raw data rate (without using video codec compression) can be roughly calculated as
follows:
If the LCD is 320x240 for QVGA and one pixel needs one bit (black or white) to present
(actually it is more because of color), then the data capacity for ONE frame is: 320 x 240 = 76.8
kbps.
If the frame rate is 5 frames per second, then the total data stream (raw data for video without
compression) is: 76.8 x 5 = 384 kbps.
Also, you need to add the additional audio data rate (details please refer to Codec FAQ ):
With the H.264 codec, the video data can be compressed. But to ensure good picture quality
having the necessary bandwidth is the KEY to a good picture because so much data that needs
to be transmitted simultaneously in both directions.
Q: What is the meaning of the letters displayed on the LCD screen when a call is made?
PCMU/H.264U: This means the Audio / Video codec used in the call. It shows audio is using
G.711 µlaw (PCMU) and video is using H.264 video codec.
86K/15FU: This shows RECEIVING video bandwidth used in the call (OSD always shows
other side bandwidth used and suppose you should know your own sending video bandwidth as
this video bit rate is configured by you in the configurations).
For example: "86K/15F" means you are receiving video bit rate using 86Kbps and 15F means it
is using 15 frame per second to send the video.
The top left and right time stamp shows "current time" and "call duration".
Q: Can I connect a TV monitor to the GXV-3000?