State-of-the-art semantic segmentation methods capture the relationship between pixels to facilitate contextual information exchange. Advanced methods utilize fixed pathways for context exchange, lacking the flexibility to harness the most relevant context for each pixel. In this paper, we present Configurable Context Pathways (CCPs), a novel model for establishing pathways for augmenting contextual information. In contrast to previous pathway models, CCPs are learned, leveraging configurable regions to form information flows between pairs of pixels. We propose TAGNet to adaptively configure the regions, which span over the entire image space, driven by the relationships between the remote pixels. Subsequently, the information flows along the pathways are updated gradually by the information provided by sequences of configurable regions, forming more powerful contextual information. We extensively evaluate the traveling, adaption, and gathering (TAG) stages of our network on the public benchmarks, demonstrating that all of the stages successfully improve the segmentation accuracy and help to surpass the state-of-the-art results. The code package is available at: https://github.com/dilincv/TAGNet.

Recent semantic segmentation methods model the relationship between pixels to construct the contextual representations. In this paper, we introduce the \emph{Region Attention Network} (RANet), a novel attention network for modeling the relationship between object regions. RANet divides the image into object regions, where we select representative information. In contrast to the previous methods, RANet configures the information pathways between the pixels in different regions, enabling the region interaction to exchange the regional context for enhancing all of the pixels in the image. We train the construction of object regions, the selection of the representative regional contents, the configuration of information pathways and the context exchange between pixels, jointly, to improve the segmentation accuracy. We extensively evaluate our method on the challenging segmentation benchmarks, demonstrating that RANet effectively helps to achieve the state-of-the-art results.

Multi-scale context information has proven to be essential for object segmentation tasks. Recent works construct the multi-scale context by aggregating convolutional feature maps extracted by different levels of a deep neural network. This is typically done by propagating and fusing features in a one-directional, top-down and bottom-up, manner. In this work, we introduce ZigZagNet, which aggregates a richer multi-context feature map by using not only dense top-down and bottom-up propagation, but also by introducing pathways crossing between different levels of the top-down and the bottom-up hierarchies, in a zig-zag fashion. Furthermore, the context information is exchanged and aggregated over multiple stages, where the fused feature maps from one stage are fed into the next one, yielding a more comprehensive context for improved segmentation performance. Our extensive evaluation on the public benchmarks demonstrates that ZigZagNet surpasses the state-of-the-art accuracy for both semantic segmentation and instance segmentation tasks.