RGB-D saliency detection aims to fuse multi-modal cues to accurately localize salient regions. Existing works often adopt attention modules for feature modeling, with few methods explicitly leveraging fine-grained details to merge with semantic cues. Thus, despite the auxiliary depth information, it is still challenging for existing models to distinguish objects with similar appearances but at distinct camera distances. In this paper, from a new perspective, we propose a novel Hierarchical Depth Awareness network (HiDAnet) for RGB-D saliency detection. Our motivation comes from the observation that the multi-granularity properties of geometric priors correlate well with the neural network hierarchies. To realize multi-modal and multi-level fusion, we first use a granularity-based attention scheme to strengthen the discriminatory power of RGB and depth features separately. Then we introduce a unified cross dual-attention module for multi-modal and multi-level fusion in a coarse-to-fine manner. The encoded multi-modal features are gradually aggregated into a shared decoder. Further, we exploit a multi-scale loss to take full advantage of the hierarchical information. Extensive experiments on challenging benchmark datasets demonstrate that our HiDAnet performs favorably over the state-of-the-art methods by large margins. The source code can be found in https://github.com/Zongwei97/HIDANet/.
17 January 2020 in IEEE Robotics and Automation Letters
The problem of 3D layout recovery in indoor scenes has been a core research topic for over a decade. However, there are still several major challenges that remain unsolved. Among the most relevant ones, a major part of the state-of-the-art methods make implicit or explicit assumptions on the scenes -e.g. box-shaped or Manhattan layouts. Also, current methods are computationally expensive and not suitable for real-time applications like robot navigation and AR/VR. In this work we present CFL (Corners for Layout), the first end-to-end model that predicts layout corners for 3D layout recovery on 360° images. Our experimental results show that we outperform the state of the art, making less assumptions on the scene than other works, and with lower cost. We also show that our model generalizes better to camera position variations than conventional approaches by using EquiConvs, a convolution applied directly on the spherical projection and hence invariant to the equirectangular distortions.
17 August 2011 in Journal of Intelligent & Robotic Systems
Organism detection plays a vital role in marine resource exploitation and marine economy. How to accurately locate the target organism object within the camouflaged and dark light oceanic scene has recently drawn great attention in the research community. Existing learning-based works usually leverage local texture details within a neighboring area, with few methods explicitly exploring the usage of contextualized awareness for accurate object detection. From a novel perspective, we in this work present a Bidirectional Collaborative Mentoring Network (BCMNet) which fully explores both texture and context clues during the encoding and decoding stages, making the cross-paradigm interaction bidirectional and improving the scene understanding at all stages. Specifically, we first extract texture and context features through a dual-branch encoder and attentively fuse them through our adjacent feature fusion (AFF) block. Then, we propose a structure-aware module (SAM) and a detail-enhanced module (DEM) to form our two-stage decoding pipeline. On the one hand, our SAM leverages both local and global clues to preserve morphological integrity and generate an initial prediction of the target object. On the other hand, the DEM explicitly explores long-range dependencies to refine the initially predicted object mask further. The combination of SAM and DEM enables better extracting, preserving, and enhancing the object morphology, making it easier to segment the target object from the camouflaged background with sharp contour. Extensive experiments on three benchmark datasets show that our proposed BCMNet performs favorably over state-of-the-art models. The code will be made available at https://github.com/chasecjg/BCMNet .
Multi-sensor clues have shown promise for object segmentation, but inherent noise in each sensor, as well as the calibration error in practice, may bias the segmentation accuracy. In this paper, we propose a novel approach by mining the Cross-Modal Semantics to guide the fusion and decoding of multimodal features, with the aim of controlling the modal contribution based on relative entropy. We explore semantics among the multimodal inputs in two aspects: the modality-shared consistency and the modality-specific variation. Specifically, we propose a novel network, termed XMSNet, consisting of (1) all-round attentive fusion (AF), (2) coarse-to-fine decoder (CFD), and (3) cross-layer self-supervision. On the one hand, the AF block explicitly dissociates the shared and specific representation and learns to weight the modal contribution by adjusting the proportion, region, and pattern, depending upon the quality. On the other hand, our CFD initially decodes the shared feature and then refines the output through specificity-aware querying. Further, we enforce semantic consistency across the decoding layers to enable interaction across network hierarchies, improving feature discriminability. Exhaustive comparison on eleven datasets with depth or thermal clues, and on two challenging tasks, namely salient and camouflage object segmentation, validate our effectiveness in terms of both performance and robustness. The source code is publicly available at https://github.com/Zongwei97/XMSNet.