The visual pathway of human brain includes two sub-pathways,i.e., the ventral pathway and the dorsal pathway, which focus on object identification and dynamic information modeling, respectively. Both pathways comprise multi-layer structures, with each layer responsible for processing different aspects of visual information. Inspired by the human visual information processing mechanism, we propose the Brain Inspired Masked Modeling (BIMM) framework, aiming to learn comprehensive representations from videos. Specifically, our approach consists of ventral and dorsal branches, which learn image and video representations, respectively. Both branches employ the Vision Transformer (ViT) as their backbone and are trained through a masked modeling method. To emulate the distinct functions of the visual cortices, we segment the encoder of each branch into three intermediate blocks and reconstruct progressive prediction targets with light weight decoders. Furthermore, drawing inspiration from the information-sharing mechanism in the brain’s visual pathways, we introduce a partial parameter sharing strategy between the branches during training. Extensive experiments demonstrate that BIMM achieves superior performance compared to the state-of-the-art methods.

Considering the close connection between action recognition and human pose estimation, we design a Collaboratively Self-supervised Video Representation (CSVR) learning framework specific to action recognition by jointly factoring in generative pose prediction and discriminative context matching as pretext tasks. Specifically, our CSVR consists of three branches: a generative pose prediction branch, a discriminative context matching branch, and a video generating branch. Among them, the first one encodes dynamic motion feature by utilizing Conditional-GAN to predict the human poses of future frames, and the second branch extracts static context features by contrasting positive and negative video feature and I-frame feature pairs. The third branch is designed to generate both current and future video frames, for the purpose of collaboratively improving dynamic motion features and static context features. Extensive experiments demonstrate that our method achieves state-of-the-art performance on multiple popular video datasets.

Recently, self-supervised video representation learning based on Masked Video Modeling (MVM) has demonstrated promising results for action recognition. However, existing methods face two significant challenges: (1) video actions involve a crucial temporal dimension, yet current masking strategies adopt inefficient random approaches that undermine low-density dynamic motion clues in videos; (2) pre-training requires large-scale datasets and significant computing resources (including large batch sizes and enormous iterations). To address these issues, we propose a novel method named Data-Efficient Masked Video Modeling (DEMVM) for self-supervised action recognition. Specifically, a novel masking strategy named Flow-Guided Dense Masking (FGDM) is proposed to facilitate efficient learning by focusing more on the action-related temporal clues, which applies dense masking to dynamic regions based on optical flow priors, while sparse masking to background regions. Furthermore, DEMVM introduces a 3D video tokenizer to enhance the modeling of temporal clues. Finally, Progressive Masking Ratio (PMR) and 2D initialization strategies are presented to enable the model to adapt to the characteristics of the MVM paradigm during different training stages. Extensive experiments on multiple benchmarks, UCF101, HMDB51, and Mimetics, demonstrate that our method achieves state-of-the-art performance in the downstream action recognition task with both efficient data and low computational cost. More interestingly, the few-shot experiment on the Mimetics dataset shows that DEMVM can accurately recognize actions even in the presence of context bias.