Net::SIP::SDP(3pm)					User Contributed Perl Documentation					Net::SIP::SDP(3pm)

NAME

       Net::SIP::SDP - Parsing and manipulation of SDP data for SIP

SYNOPSIS

	 my $sdp = Net::SIP::SDP->new( sdp_string );
	 my @media = $sdp->get_media;

DESCRIPTION

       Net::SIP::SDP can parse and manipulate SDP data.

       It's not a general purpose SDP class (like Net::SDP) but designed to work with SDP data contained in SIP packets and for easy extraction
       and manipulation (for NAT etc) of media information contained in the SDP.

       The class is also designed for easy creation of SDP bodies in the context of the rest of Net::SIP::*.

EXAMPLES

	 # creation based on media data
	 my $sdp = Net::SIP::SDP->new(
	       { addr => '192.168.0.1' },
	       { port => 2012, proto => 'RTP/AVP', media => 'audio', fmt => 0 },
	       { port => 2014, proto => 'RTP/AVP', media => 'video', fmt => 0 },
	 );

	 # parse from string
	 my $sdp = Net::SIP::SDP->new( sdp_string );

	 # extract all media data
	 my @media = $sdp->get_media;

	 # and replace them with new addr + port (for NAT)
	 my @new_media,;
	 foreach (@media) {
	       my ($port,@socks) = create_rtp_sockets( '192.168.178.1', $_->{range} );
	       push @new_media, [ '192.168.178.1', $port ];
	       ...
	 }
	 $sdp->replace_media_listen( @new_media );

CONSTRUCTOR

       new Default constructor.  Depending on kind of arguments branches into new_from_string or new_from_parts.  See there.

       new_from_string ( STRING )
	   Creates object from STRING containing the SDP data.	Raises an exception (e.g. die()) if SDP is invalid.

       new_from_parts ( \%GLOBAL, @MEDIA )
	   Creates object from specification.  %GLOBAL describes the global keys, usually only a common "addr" for all media but any of the keys
	   defined in RFC2327 can be used.

	   @MEDIA is a list of hash references, one hash for each media part. These hashes can contain as keys the one-letter keys specified in
	   RFC2327 and/or special keys for constructing the 'c' and 'm' line:

	   addr - The address, used in the 'c' line.
	   port -  The port number
	   range - Range of ports, for RTP/AVP defaults to 2, else 1
	   media - The media typ, e.g. 'audio','video',...
	   proto - Transport protocol, ususally 'RTP/AVP' or 'udp'

	   If the SDP should contain multiple values for the same key in the same media section on can specifiy the value for the key as a @list
	   instead of a string (this is often the case for 'a' lines).

METHODS

       as_string
	   Returns string representation for object.

       content_type
	   Returns 'application/sdp'

       get_media
	   Returns list of all media described in the SDP. If the caller expects an array the result will be a list, otherwise a reference to a
	   list.

	   Each element of the list is a hash with the following keys:

	   addr - IP4/IP6 address for media
	   port - Start port
	   range - Range for ports
	   proto - Media proto, usually 'RTP/AVP' or 'udp'
	   media - Media typ, usually 'audio', 'video' or 'data'
	   fmt - Format info from media line as @list, e.g "[ 0,10,5 ]".
	   lines - All lines from media description as @list of [ key,value ].

	   WARNING! You should never manipulate the values you got from this function, because this might affect the objects internals.

       replace_media_listen ( NEW_MEDIA )
	   Replaces the exisisting media in the object with new media. Useful for NAT.

	   NEW_MEDIA is ether an array or a reference to an array. Each element in the list consists of the new [ addr,port ] mapping for the
	   matching media entry.

	   The number of entries in the list should be the same as the number of media entries in the object ( see get_media ). If this is not the
	   case it will "die()".

       name2int ( NAME, INDEX )
	   Returns the RTP payload id for NAME (e.g. "telephone-event/8000").  INDEX is the index into the list of media information, matching the
	   list returned from get_media. INDEX can also be 'audio','video'.., which will then lookup at the first matching entry in the media
	   list.

perl v5.14.2							    2012-06-08							Net::SIP::SDP(3pm)