Writing sdr plugins

Sdr plug-in configuration files follow a strict format of grouped attribute:value pairs with one attribute value pair per line. Leading whitespace is ignored. Whitespace in the value part of an attribute:value pair is significant.

Compulsory fields

For a format or tool definition file, the following attributes are compulsory and should be in the following order: 
  media:media
  proto:protocol
  tool:tool-name
See the SDP specification for definitions of media and protocol. Tool-name is the name of the tool you wish to be started to send/receive this session.

Optional header fields

protoname

As the protocol will often not be very meaning full to humans, these may be followed by further definition: 
  protoname:human readable versions of protocol
Protoname is used at configure menus and labels on the user interface.

create

Most plugins define media and formats that you wish to be able to announce. However, some may be just for backwards compatibility so you can receive them but do not wish to announce them. If this is the case, you can use the create field to specify that you don't wish this plugin to contribute to the session creation menus and options: 
  create:no

Format definitions

After these definitions should come one or more format definitions. The minimal form of a format definition is: 
  fmt:format
See the SDP specification for a more complete
  • Media Descriptions
  • Detailed Timing ./usr/share/doc/sdr/html/node4.html0000644000000000000000000000222307154747065016042 0ustar rootroot Links to the World Wide Web

    Links to the World Wide Web

    A session announcement can contain an Uniform Resource Locator (URL) as a link to related information in the world wide web. The preferences menu determines how sdr follows such references - three options are supported:

    If you have an colour display of depth 8 bits, using the built in browser is recommended as external browsers use a significant number of the 256 available colours, leaving you with few colours remaining for any tools you wish to use in a multimedia conference. If you have a 24bit display, external browsers are likely to provide you with better performance and prettier displays than the built-in browser. When creating a session, it is recommended that the URL be tested (using the Test button) as typing mistakes here will make the URL useless. ./usr/share/doc/sdr/html/node5.html0000644000000000000000000000363007154747065016046 0ustar rootroot Media Descriptions

    Media Descriptions

    Media descriptions are the main reason for describing a session, as they allow the receiver of an announcement to start the correct media tools directly from sdr with all the correct flags and settings to join the conference. Sdr allows you to create conferences with up to one media tool of each of the following types:

    In fact sdr can receive and start sessions with more than one of each media, but the standard interface does not permit the creation of such sessions in an effort to make the session creation interface simpler to use. To include a media in your session, select the media by clicking on the left ``X" button When a media is selected, a default media format will be selected, along with default addresses, transport protocol and ports. The media format and transport protocol can be changed using the relevant pull down menus. The address and port are allocated in such a way that they should avoid clashes with other scheduled sessions - the addresses sdr provides should normally be used, although user specified ones can be substituted if required. In particular, ports are chosen such that rate-limiting in Mbone routers will preferentially forward audio rather than video when a multicast tunnel is congested. If everyone you expect to participate in your session is likely to wish to receive all the media you have selected, then using one multicast address for all your media is appropriate. If some receivers are likely to not wish to receive some media - for example some sites have insuf