Embodiments that provide multi-video synthesis are disclosed. In accordance with one embodiment, multi-video synthesis includes breaking a main video into a plurality of main frames and break a supplementary video into a plurality of supplementary frames. The multi-video synthesis also includes assigning one or more supplementary frames into each of a plurality of states of a Hidden Markov Model (HMM), where each of the plurality of states corresponding to one or more main frames. The multi-video synthesis further includes determining optimal frames in the plurality of main frames for insertion of the plurality of supplementary frames based on the plurality of states and visual properties. The optimal frames include optimal insertion positions. The multi-video synthesis additionally includes inserting the plurality of supplementary frames into the optimal insertion positions to form a synthesized video.