Method for real-time broadcasting of multimedia files during a videoconference, without interrupting communication, and a man-machine interface therefor

A method of broadcasting data files, including multimedia files, during a video conference communication, from a sending terminal able to establish communication with at least one receiving terminal, said at least one receiving terminal having audio and video sources, said method comprising:

• implementing a dialogue, when said video conference communication is established, between said sending terminal and said at least one receiving terminal to negotiate at least one communication parameter for compliance with constraints that are fixed for audio and video channels opened for said video conference communication and for said at least one receiving terminal;
• and
• complying, during said broadcasting of a multimedia file, with said constraints,
• wherein said communication parameter includes a video coding standard,
• wherein said broadcasting of said data files by said sending terminal is carried out in real time with said video conference communication, without breaking said video conference communication, and using said audio and video channels, and
• wherein said sending terminal has a video capture source, and wherein said video capture source issues a video that is decoded and mixed in real time with a video of a multimedia file to be broadcast, and then coded according to said negotiated video coding standard.