consecutive frames within a short time have similar coherent appearance
The coherence of color can be used to design pretext tasks for self-supervised learning
One way to utilize color coherence is to use video colorization as a pretext task for self-supervised video feature learning.
Video colorization is a task to colorize gray-scale frames into colorful frames
Vondrick et al. proposed to constrain colorization models to solve video colorization by learning to copy colors from a reference frame
Given the reference RGB frame and a gray-scale image, the network needs to learn the internal connection between the reference RGB frame and gray-scale image to colorize it.
tackle video colorization by employing a fully convolution neural network
Tran et al. proposed an U-shape convolution neural network for video colorization [160]
The color coherence in videos is a strong supervision signal