1. A method comprising: receiving, at a computing system, a first stream of video images corresponding to a videoconference; receiving, at the computing system, a second stream of video images corresponding to the videoconference that is different from the first stream of video images; accessing, by the computing system, metadata associated with the first stream of video images and specifying an upper alignment reference height and a lower alignment reference height within the video images of the first stream, wherein the upper alignment reference height is associated with an approximate head height of one or more videoconference participants within the video images; based on the accessed metadata specifying the upper alignment reference height and the lower alignment reference height within the video images of the first stream, defining, by the computing system, a layout for concurrently displaying the first stream of video images and the second stream of video images at a location that substantially aligns a top edge of the video images of the second stream with the upper alignment reference height within the video images of the first stream and that substantially aligns a bottom edge of the video images of the second stream with the lower alignment reference height within the video images of the first stream.