332 research outputs found

    Robust and Real-time Deep Tracking Via Multi-Scale Domain Adaptation

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    Visual tracking is a fundamental problem in computer vision. Recently, some deep-learning-based tracking algorithms have been achieving record-breaking performances. However, due to the high complexity of deep learning, most deep trackers suffer from low tracking speed, and thus are impractical in many real-world applications. Some new deep trackers with smaller network structure achieve high efficiency while at the cost of significant decrease on precision. In this paper, we propose to transfer the feature for image classification to the visual tracking domain via convolutional channel reductions. The channel reduction could be simply viewed as an additional convolutional layer with the specific task. It not only extracts useful information for object tracking but also significantly increases the tracking speed. To better accommodate the useful feature of the target in different scales, the adaptation filters are designed with different sizes. The yielded visual tracker is real-time and also illustrates the state-of-the-art accuracies in the experiment involving two well-adopted benchmarks with more than 100 test videos.Comment: 6 page

    Deep Sketch Hashing: Fast Free-hand Sketch-Based Image Retrieval

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    Free-hand sketch-based image retrieval (SBIR) is a specific cross-view retrieval task, in which queries are abstract and ambiguous sketches while the retrieval database is formed with natural images. Work in this area mainly focuses on extracting representative and shared features for sketches and natural images. However, these can neither cope well with the geometric distortion between sketches and images nor be feasible for large-scale SBIR due to the heavy continuous-valued distance computation. In this paper, we speed up SBIR by introducing a novel binary coding method, named \textbf{Deep Sketch Hashing} (DSH), where a semi-heterogeneous deep architecture is proposed and incorporated into an end-to-end binary coding framework. Specifically, three convolutional neural networks are utilized to encode free-hand sketches, natural images and, especially, the auxiliary sketch-tokens which are adopted as bridges to mitigate the sketch-image geometric distortion. The learned DSH codes can effectively capture the cross-view similarities as well as the intrinsic semantic correlations between different categories. To the best of our knowledge, DSH is the first hashing work specifically designed for category-level SBIR with an end-to-end deep architecture. The proposed DSH is comprehensively evaluated on two large-scale datasets of TU-Berlin Extension and Sketchy, and the experiments consistently show DSH's superior SBIR accuracies over several state-of-the-art methods, while achieving significantly reduced retrieval time and memory footprint.Comment: This paper will appear as a spotlight paper in CVPR201

    Zero-Shot Sketch-Image Hashing

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    Recent studies show that large-scale sketch-based image retrieval (SBIR) can be efficiently tackled by cross-modal binary representation learning methods, where Hamming distance matching significantly speeds up the process of similarity search. Providing training and test data subjected to a fixed set of pre-defined categories, the cutting-edge SBIR and cross-modal hashing works obtain acceptable retrieval performance. However, most of the existing methods fail when the categories of query sketches have never been seen during training. In this paper, the above problem is briefed as a novel but realistic zero-shot SBIR hashing task. We elaborate the challenges of this special task and accordingly propose a zero-shot sketch-image hashing (ZSIH) model. An end-to-end three-network architecture is built, two of which are treated as the binary encoders. The third network mitigates the sketch-image heterogeneity and enhances the semantic relations among data by utilizing the Kronecker fusion layer and graph convolution, respectively. As an important part of ZSIH, we formulate a generative hashing scheme in reconstructing semantic knowledge representations for zero-shot retrieval. To the best of our knowledge, ZSIH is the first zero-shot hashing work suitable for SBIR and cross-modal search. Comprehensive experiments are conducted on two extended datasets, i.e., Sketchy and TU-Berlin with a novel zero-shot train-test split. The proposed model remarkably outperforms related works.Comment: Accepted as spotlight at CVPR 201

    Numerical Simulation Method for Fracture Effect of Corroded Steel Strand Under Tension

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    Steel strand presents characteristic pitting corrosion in chloride environment, which leads PC structures to a serious structural failure even with light presentational corrosion. So it is necessary to analyze the fracture effect of steel strand caused by pitting corrosion. The theoretical analyses are difficult for the presence of complicated threedimension pits, so numerical method becomes a feasible choice. A numerical simulation method for fracture effect of corroded steel strand under tension by the ANSYS software is introduced in this paper, which contains mainly four issues such as fracture criterion, constitutive relation, geometrical models, and simplified mechanical models. The Mises strain is fixed as the fracture criterion parameter because the fracture is stemmed from overlarge plastic deformation. A type of three-line constitutive relation model based on experiment is fixed. The geometrical models of corroded wires with one of the two type pits, namely spheroidic pit and anticlastic pit, are both came from the cylinder cut by a surface rotated from a segment of circular arc. A simplified mechanical model is fixed as the analyzing model, which is a cylinder with 50 mm length and one pit, one end is fixed rigidly and another end is restricted along the longitudinal axis and applied with area load
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