Techniques for video conferencing include receiving a stream of video slices from a participant, designating the video slices as a primary sub-picture of a frame of video, encoding, with a first encoder, a first secondary sub-picture of the frame of video to obtain an encoded first secondary sub-picture of a frame of video, encoding, with a second encoder, a second secondary sub-picture of the frame of video to obtain an encoded first secondary sub-picture of a frame of video, combining the primary sub-picture with the encoded first secondary sub-picture to obtain a first video stream, combining the primary sub-picture with the encoded second secondary sub-picture to obtain a second video stream, and transmitting the first and second video streams to respective recipients.