  Recent advances in high refresh rate displays as well as the increased
interest in high rate of slow motion and frame up-conversion fuel the demand
for efficient and cost-effective multi-frame video interpolation solutions. To
that regard, inserting multiple frames between consecutive video frames are of
paramount importance for the consumer electronics industry. State-of-the-art
methods are iterative solutions interpolating one frame at the time. They
introduce temporal inconsistencies and clearly noticeable visual artifacts.
  Departing from the state-of-the-art, this work introduces a true multi-frame
interpolator. It utilizes a pyramidal style network in the temporal domain to
complete the multi-frame interpolation task in one-shot. A novel flow
estimation procedure using a relaxed loss function, and an advanced,
cubic-based, motion model is also used to further boost interpolation accuracy
when complex motion segments are encountered. Results on the Adobe240 dataset
show that the proposed method generates visually pleasing, temporally
consistent frames, outperforms the current best off-the-shelf method by 1.57db
in PSNR with 8 times smaller model and 7.7 times faster. The proposed method
can be easily extended to interpolate a large number of new frames while
remaining efficient because of the one-shot mechanism.
