The task of object segmentation in videos is usually accomplished by processing appearance and motion information separately using standard 2D convolutional networks, followed by a learned fusion of the two sources of information. On the other hand, 3D convolutional networks have been successfully applied for video classification tasks, but have not been leveraged as effectively to problems involving dense per-pixel interpretation of videos compared to their 2D convolutional counterparts and lag behind the aforementioned networks in terms of performance. In this work, we show that 3D CNNs can be effectively applied to dense video prediction tasks such as salient object segmentation. We propose a simple yet effective encoder-decoder network architecture consisting entirely of 3D convolutions that can be trained end-to-end using a standard cross-entropy loss. To this end, we leverage an efficient 3D encoder, and propose a 3D decoder architecture, that comprises novel 3D Global Convolution layers and 3D Refinement modules. Our approach outperforms existing state-of-the-arts by a large margin on the DAVIS'16 Unsupervised, FBMS and ViSal dataset benchmarks in addition to being faster, thus showing that our architecture can efficiently learn expressive spatio-temporal features and produce high quality video segmentation masks. Our code and models will be made publicly available.

本文提出了一种基于3D全卷积神经网络的编码-解码网络结构，将其应用于视频中的显著对象分割。尝试使用全3D卷积来处理外观和运动信息从而实现密集视频预测，并通过3D全局卷积层和3D细化模块进行编码和解码操作。作者将其应用于DAVIS'16无监督，FBMS和ViSal数据集基准测试中，结果表明其效果优于现有状态艺术，同时速度更快，能够高效地学习空间 - 时间特征并产生高质量的视频分割掩码。

为视频物体分割提出三维卷积的论点