A method for generating a video output signal. The method may include receiving a plurality of input video signals from each of the participants. Each of the input video signals may have a plurality of input frames. Each of the input frames may have a source slice carrying an image. Each of the input frames may be encoded using the respective reference frame at an encoding time. The method may include a step for generating the video output signal for transmission to the participants. The video output signal may comprise a plurality of output frames. A first of the output frames generally has at least a first slice having (a) a first coded portion carrying the image from a first of the participants and (b) a first unencoded portion for the image from a second of the participants. A second of the output frames generally has at least a second slice having (a) a second coded portion carrying the image from the second participant and (b) a second unencoded portion for the image from the first participant. The frames of the video output signal are generated as soon as one of the frames of the video input signal are received.