Glossary

H.239 is an ITU-T recommendationfor role management and additional media channels for H.3xx-series terminals. Sets forth a way to have multiple video channels (e.g., one for conferencing, another for presentation) within a single session (call).

H.239 is widely used by H.323 video conferencing systems to support dual video mechanisms, where a conference call includes a video stream from the camera, showing the people who are talking alongside an additional video stream of a presentation which is being fed from a PC.