The MCU can decode and then re-encode incoming content to ensure that the majority of participants can receive the content. This is the Transcoded content mode.
The MCU can also retransmit the content without having to decode it, which is known as Passthrough mode. In this mode, the incoming content packet stream is repackaged and sent to endpoints in the conference that are capable of decoding the original stream. Passthrough mode does not use up a content port for that conference.
The MCU also has a Hybrid content mode. In Hybrid mode, the incoming content stream is passed through to participants who are able to support the same codec as the original content stream (the Passthrough content stream). The MCU also encodes a stream, using the specified Outgoing transcoded codec, for endpoints who cannot decode the Passthrough content stream. Hybrid mode uses up a video port.
Disabled: The MCU does not transmit content.
Passthrough: The MCU does not transcode the content before transmission. The data is simply repackaged then sent to endpoints that support the original codec.
Hybrid: The MCU sends a passthrough stream to eligible endpoints, and a transcoded stream to other endpoints that advertise support for the Outgoing transcoded codec.
Transcoded: The MCU decodes the incoming stream and re-encodes it using the Outgoing transcoded codec, before sending it to all endpoints that support the Outgoing transcoded codec.
Sending of passthrough content to or from endpoints over encrypted connections is not supported. Endpoints with encryption only will receive transcoded content in hybrid mode. Endpoints that can only support resolutions below the minimum threshold will also only receive transcoded in hybrid, and no content in passthrough mode. Content streaming is not supported in passthrough mode but is in hybrid mode. Content previews are not supported in passthrough mode but is supported for hybrid content. In passthrough mode a black panel is displayed.
A default content mode can be set in the conference template.
Note that because ConferenceMe uses a non-standards compliant protocol to send media, ConferenceMe clients cannot send or receive passthrough content.