Grandstream Networks GVC3200 Administration Manual page 44

It should be noted that the "ptime" value for the SDP will change with different
configurations here. This value is related to the codec used and the actual frames
transmitted during the in payload call. e.g.: if set to 2 and the first codec is G.729,
Voice Frames Per G.711 or G.726, the "ptime" value is 20ms for the SDP. If the TX exceeds the
TX maximum allowable value, the device will use and save the maximum allowed value
according to what the first codec is. For end users, it is recommended to use the
default setting, as incorrect settings may influence the audio quality. The default
setting is "2".
It is used to select encoding rate for G.722.1 codec. It supports 24kbps or 32kbps.
G.722.1 Rate
The default setting is "24kbps encoding rate".
G.722.1 Payload It is used to configure payload type for G.722.1 codec. The valid range is 100-126.
Type The default setting is "104".
Opus Payload It is used to configure payload type for Opus codec. The valid range is 96-126. The
Type default setting is "123".
Use First
Matching If set to "Yes", the device will use the first matching vocoder in the sent 200OK SDP
Vocoder in 200OK as the codec. The default setting is "No".
SDP
If set to "Yes", the RFC5168 mechanism will be enabled for video call. RFC5168
Enable RFC5168
allows SIP party to request the sender to refresh its video frame in H.264, or refresh
Support
the full picture in VP8. The default setting is "Yes".
If enabled, the video sender will temporarily allocate part of the bandwidth to one data
channel to send FEC data to system, thus to improve the video quality the receiver
Enable Video FEC
gets. Enabling this function will take up part of bandwidth and reduce call rate. The
default setting is "Yes".
If set to 0, FEC is not sent by separate port. If set 1, FEC is sent by separate port.
Video FEC Mode
Default setting is 0.
FEC Payload It is used to configure FEC payload type. The range is 96-127. The default setting is
Type 120.
If set to "Yes", You can control the camera of the opposite side for video call, but the
Enable FECC opposite site must support FECC, and allow remote control on its local camera. The
default setting is "Yes".
FECC H.224 It is used to configure FECC H.224 payload type. The valid range is from 96 to 127.
The default value is 125.
Payload Type
H.264 Payload
It is used to configure the H.264 codec message payload type format. The default
Type
setting is 99. The valid range is from 96 to 127.
GVC3200/3202 Administration Guide
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