1. A system, comprising: a division component to break a main video into a plurality of main frames, and to break a supplementary video into a plurality of supplementary frames; a modeling component to assign one or more supplementary frames into each of a plurality of states of a Hidden Markov Model (HMM), and correspond each of the plurality of states to one or more of the plurality of main frames; a detection component to determine optimal frames that include optimal insertion positions in the plurality of main frames for insertion of the plurality of supplementary frames based on the plurality of states and visual properties; an insertion component to insert the plurality of supplementary frames into the optimal insertion positions to form a synthesized video; and a blend component to blend the inserted supplementary frames and the optimal frames of the synthesized video.