CODEC is capable of coding or decoding a digital data stream or signal by implementing an algorithm. Codecs and priorities 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. An incorrect RTPmap may cause the bad audio quality even unable to set up a call.
Here we are going to list the corresponding attributes of these codecs, please be careful and not to change the value of RTPmap.
The corresponding attributes of the codec are listed as follows: