Codecs

Codecs are used to convert analog to digital voice signals and vice versa.

These options set preferred codecs used by the extension.

TIP: If some of the desired codecs is disabled (cannot be selected), navigate to 'Settings: Servers: Edit: Default Codecs' and enable them under the 'Local' group.

Disallow: Set the codecs extension to not allowed to use (ex. This field is very unique. In order to work properly, this setting is automatically set to 'Disallow All' and it cannot be modified).

Allow: Set the codecs extension to allowed to use (ex. Only the codecs set under 'Settings: Server' will be available to choose from).

Video Support: Set this option to Yes to enable SIP video support.

Force codec on outbound trunk channel: With this option you can force codec use for outbound trunk calls (ex. iLBC)

Auto-Framing (RTP Packetization) If autoframing is turned on, the system will choose the packetization level based on remote ends preferences. (ex. If the remote end requires RTP packets to be of 30 ms, your CloudPBX system will automatically send packets of this size if this option is turned on. Default is set to 20 ms and also depends on the codecs minimum frame size like G.729 which has 10 ms as a minimum).


Codecs:

    • ITU G.711 ulaw - 64 Kbps, sample-based, used in US

    • ITU G.711 alaw - 64 Kbps, sample-based, used in Europe

    • ITU G.723.1 - 5.3/6.3 Kbps, 30ms frame size

    • ITU G.726 - 16/24/32/40 Kbps

    • ITU G.729 - 8 Kbps, 10ms frame size

    • GSM - 13 Kbps (full rate), 20ms frame size

    • iLBC - 15Kbps,20ms frame size: 13.3 Kbps, 30ms frame size

    • Speex - 2.15 to 44.2 Kbps

    • LPC10 - 2.5 Kbps

    • H.261 Video - Used over ISDN lines with resolution of 352x288

    • H.263 Video - Low-bit rate encoding solution for video conferencing

    • H.263+ Video - Extension of H.263 that provides additional features that improve compression over packet switched networks.