sdp

type Codec struct {
	PT    uint8  // 7-bit payload type we need to put in our RTP packets
	Name  string // e.g. PCMU, G729, telephone-event, etc.
	Rate  int    // frequency in hertz.  usually 8000
	Param string // sometimes used to specify number of channels
	Fmtp  string // some extra info; i.e. dtmf might set as "0-16"
	// contains filtered or unexported fields
}

type Media struct {
	Type      MediaType         // audio, video, text, application, message, etc.
	Proto     TransportProtocol // RTP, SRTP, UDP, UDPTL, TCP, TLS, etc.
	Port      uint16            // Port number (0 - 2^16-1)
	NumPorts  int               // If multiple ports are being used
	Addr      string            // The address from the media-specific `c=` line, if present
	Direction MediaDirection    // sendrecv, sendonly, recvonly, inactive
	Codecs    []*Codec          // Collection of codecs of a specific type.
	Ptime     int               // Transmit frame every N milliseconds (default 20)
	Maxptime  int               // Maximum number of milliseconds per packet (default 20)
	Attrs     [][2]string       // Attributes for this media description
	Other     [][2]string       // Unrecognized properties for this media description
}

type MediaDirection string

type MediaType string

type Origin struct {
	User    string // First value in o= line
	ID      string // Second value in o= line
	Version string // Third value in o= line
	Addr    string // Tracks IP of original user-agent
}

type SDP struct {
	Origin    *Origin        // This must always be present
	Addr      string         // Connect to this IP; never blank (from c=)
	Media     []*Media       // Media descriptions, e.g. audio, video
	Session   string         // s= Session Name (default "-")
	Time      string         // t= Active Time (default "0 0")
	Direction MediaDirection // If 'a=sendonly', 'a=recvonly', or 'a=inactive' was specified in SDP
	Attrs     [][2]string    // a= lines we don't recognize
	Other     [][2]string    // Other description
}

type TransportProtocol string