Video Frame Interpolation via Cyclic Fine-Tuning and Asymmetric Reverse Flow

The objective in video frame interpolation is to predict additional in-between frames in a video while retaining natural motion and good visual quality. In this work, we use a convolutional neural network (CNN) that takes two frames as input and predicts two optical flows with pixelwise weights. The flows are from an unknown in-between frame to the input frames. The input frames are warped with the predicted flows, multiplied by the predicted weights, and added to form the in-between frame. We also propose a new strategy to improve the performance of video frame interpolation models: we reconstruct the original frames using the learned model by reusing the predicted frames as input for the model. This is used during inference to fine-tune the model so that it predicts the best possible frames. Our model outperforms the publicly available state-of-the-art methods on multiple datasets.