| Configuring the Audio Settings |
131
Parameter
Description
Configuration Method
H.265 Mode
H.265 video codec.
•
VBR
- the output data rate of
the H.265 codec varies per
time segment. You can save
nearly half the bandwidth.
•
CBR
- the output data rate of
the H.265 codec is constant.
If the latency issue appears
in the call or video image is
abnormal, it may result from
packet loss, you can select
this value to try to fix this
issue.
Default
: VBR.
Web user interface
DTMF
DTMF is the signal sent from the system to the network, which is generated when pressing the keypad during a call.
Each key pressed generates one sinusoidal tone of two frequencies. One is generated from a high frequency group and
the other from a low frequency group.
•
•
•
Configuring DTMF for SIP Protocol
•
Configuring DTMF for H.323 Protocol
DTMF Keypad
The DTMF keypad is laid out in a 4×4 matrix, with each row representing a low frequency, and each column
representing a high frequency. Pressing a digit key (such as '1') will generate a sinusoidal tone for each of two
frequencies (697 and 1209 hertz (Hz)). The switch can decode the frequency group and locate the corresponding key.
DTMF Keypad Frequencies:
1209 Hz
1336 Hz
1477 Hz
1633 Hz
697 Hz
1
2
3
A
770 Hz
4
5
6
B
852 Hz
7
8
9
C
941 Hz
*
0
#
D
Transmission Ways of DTMF
Three ways to transmit DTMF tones are as below: RFC2833, INBAND, SIP INFO.
RFC 2833
In-band transmission method. DTMF tones are transmitted by RTP, and the RFC 2833 packets are marked by
TeleponeEvent (RTP PayloadType). One DTMF tone consists of several RTP packets with the same timestamps,