Configuring Audio Features
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2. Select the desired value from the pull-down list of Dual-Headset.
3. Click Confirm to accept the change.
CODEC is an abbreviation of COmpress-DECompress, capable of coding or decoding a
digital data stream or signal by implementing an algorithm. The object of the algorithm
is to represent the high-fidelity audio signal with minimum number of bits while retaining
the quality. This can effectively reduce the frame size and the bandwidth required for
audio transmission.
The default codecs used on IP phones are summarized in the following table:
In addition to the codecs introduced above, IP phones also support codecs: G723_53,
G723_63, G726-16, G726-24, G726-32, G726-40 (Codecs G726-16, G726-24 and G726-40
are not applicable to SIP-T21P and SIP-T19P IP phones). Codecs and priorities of these
codecs are configurable on a per-line basis. The attribute “rtpmap” is used to define a
mapping from RTP payload codes to a codec, clock rate and other encoding
parameters.