Mobile terminal and hub apparatus for use in a video communication system

A hub apparatus comprising:

• a receiving unit configured to receive from each mobile terminal of a plurality of mobile terminals, a video stream, and a current speaker indicator indicating whether the user of each mobile terminal is speaking,
• a generation unit operatively connected to the receiving unit and configured to generate an output video communication stream based on the plurality of video streams received from the plurality of mobile terminals, and
• a processing unit configured to extract a voice timbre pattern model from an input audio signal to calculate a correlation parameter percentage value based on a probability of similarity between the extracted voice timbre pattern model and one of a plurality of voice timbre pattern models stored in a storage of one of the mobile terminals, and wherein each of the plurality of voice timbre pattern models stored in the storage is associated with different corresponding users of the same one of the mobile terminals, and
• wherein the current speaker indicator is generated based on the correlation parameter and is indicative of a high probability of similarity between the extracted voice timbre pattern model and the voice timbre pattern model that an identity of the one or more of the users of the mobile terminal is known and is speaking;
• wherein the processing unit repetitively generates the current speaker indicator with a fixed period of repetition over time to provide up-to date information according to a pace corresponding to the hub apparatus and an ability to track a current speaker during a conversation and to avoid an excessive processing during voice timbre pattern extraction;
• and
• wherein the hub apparatus controls the pace at which the current speaker repetitively indicator is generated and sent by transmission of a timing signal to each of the plurality of mobile terminals comprising the pace at which the current speaker indicator must be repetitively generated by the mobile terminal and subsequently sent to the hub apparatus.