TSG SA WG4 Codec deals with the specifications for speech, audio, video, and multimedia codecs, in both circuit-switched and packet-switched environments. Other topics within the mandate of SA WG4 are: quality evaluation, end-to-end performance, and interoperability aspects with existing mobile and fixed networks (from codec point of view).
Useful links and information
| About TSG SA4 | List of elected officials |
| Documents | Meeting documents |
| Specifications | |
| Work items | |
| Meetings | Next meeting information & previous meeting reports and documents |
| Liaisons Statements | |
| Full SA4 meeting calendar | |
| General info | Email exploder lists |
| Contact SA4 |
| SA Working groups and Ad Hoc groups | |
|---|---|
| TSG SA Plenary | |
| TSG SA WG1 | Services |
| TSG SA WG2 | Architecture |
| TSG SA WG3 | Security |
| TSG SA WG4 | Codec |
| TSG SA WG5 | Telecom Management |
Terms of reference
The responsibilities of WG4 (Codec) include the following items:
- Development and maintenance of specifications for speech, audio, video, and multimedia codecs, as required to enable services specified for 3G terminals and systems.
- Guidance to other 3GPP groups concerning required QoS parameters and other system implications, including channel coding requirements, imposed by different multimedia codecs in both circuit-switched and packet-switched environments.
- Speech, audio, video, and multimedia quality evaluation (including new evaluation methods, testing, verification, characterisation, selection criteria)
- End-to-end performance, including terminal characteristics, of speech, audio, video, and multimedia services.
- Interoperability aspects with existing mobile and fixed networks from the codec point of view.
In conducting its work, the Codec WG will strive to specify the best possible technical solutions at the same time as considering the planned global use of the codecs and the flexibility needs imposed by different regional requirements and preferences, including possible differences in quality/capacity trade-offs.

