US Patent 9179078 Combining multiple video streams

Methods, computer-readable media, and systems are provided for combining multiple video streams. One method for combining the multiple video streams includes extracting a sequence of media frames (224-1/224-2) from presenter (222-1) video and from shared digital rich media (222-2) video (340). The media frame (224-1/224-2) content is analyzed (226) to determine a set of space and time varying alpha values (228/342). A compositing operation (230) is performed to produce the combined video frames (232) based on the content analysis (226/344).