nils-herrmann/clean_scirepeval huggingface dataset:
Hyperspectral remote sensing image classification based on the integration of support vector machine and random forest

Support vector machine (SVM) and Random Forest (RF) have been developed to improve the accuracy of hyperspectral remote sensing (HRS) image classification significantly in recent years. Due to the different characteristics and obvious diversity between SVM and RF, we propose two integration approaches which combine SVM and Random Forest to classify the HRS image. The proposed method called DWDCS is examined by two hyperspectral images and it can acquire the higher overall accuracy and also improve the accuracy of each classes. Experimental results indicate that the proposed approaches have a great deal of advantages in classifying HRS image.
Hyperspectral Remote Sensing Image Classification Based on Rotation Forest

In this letter, an ensemble learning approach,  Forest, has been applied to hyperspectral remote sensing image classification for the first time. The framework of Rotation Forest is to project the original data into a new feature space using transformation methods for each base classifier (decision tree), then the base classifier can train in different new spaces for the purpose of encouraging both individual accuracy and diversity within the ensemble simultaneously. Principal component analysis (PCA), maximum noise fraction, independent component analysis, and local Fisher discriminant analysis are introduced as feature transformation algorithms in the original Rotation Forest. The performance of Rotation Forest was evaluated based on several criteria: different data sets, sensitivity to the number of training samples, ensemble size and the number of features in a subset. Experimental results revealed that Rotation Forest, especially with PCA transformation, could produce more accurate results than bagging, AdaBoost, and Random Forest. They indicate that Rotation Forests are promising approaches for generating classifier ensemble of hyperspectral remote sensing.
Improved Binary Partition Tree construction for hyperspectral images: Application to object detection

This paper discusses hierarchical region-based representation using Binary Partition Tree in the framework of hyperspectral data. Based on region merging techniques, this region-based representation reduces the number of elementary primitives compared to the pixel-based representation and allows a more robust filtering, segmentation, classification or information retrieval. The work presented here proposes a strategy for merging hyperspectral regions using a new association measure depending on canonical correlations relating principal coordinates. To demonstrate an example of BPT usefulness, a pruning strategy aiming at object detection is discussed. Experimental results demonstrate the good performances of BPT.
Spatio-temporal cellular automata-based filtering for image sequence denoising

This work describes a novel spatio-temporal cellular automata-based filtering algorithm (st-CAF) intended for performing image sequence denoising processes. The approach presents several advantages over more traditional single frame denoising techniques presented in the literature or even over their adaptation to sequences. Especially the fact that the cellular automaton used is able to contemplate information concerning the type of noise through the use of specific sequences to tune the algorithm, as well as temporal information by means of a spatio-temporal neighborhood when processing each pixel of the sequence. These two elements lead to significant improvements in the results with respect to simple spatial or temporal sets of neighbors.
Segmentation and Classification of Hyperspectral Images Using Minimum Spanning Forest Grown From Automatically Selected Markers

A new method for segmentation and classification of hyperspectral images is proposed. The method is based on the construction of a minimum spanning forest (MSF) from region markers. Markers are defined automatically from classification results. For this purpose, pixelwise classification is performed, and the most reliable classified pixels are chosen as markers. Each classification-derived marker is associated with a class label. Each tree in the MSF grown from a marker forms a region in the segmentation map. By assigning a class of each marker to all the pixels within the region grown from this marker, a spectral-spatial classification map is obtained. Furthermore, the classification map is refined using the results of a pixelwise classification and a majority voting within the spatially connected regions. Experimental results are presented for three hyperspectral airborne images. The use of different dissimilarity measures for the construction of the MSF is investigated. The proposed scheme improves classification accuracies, when compared to previously proposed classification techniques, and provides accurate segmentation and classification maps.
A Combined Support Vector Machines Classification Based on Decision Fusion

Decision fusion for classification of hyperspectral data from urban area is addressed. Classical classification algorithms are based on the spectral signature of the individual classes. For urban area, where classes could be defined in accordance with the shape of the structure, these methods have a major drawback: no spatial information are contained in the spectrum. A new method has been proposed that considers the spatial content, but it reduces the spectrum to a small number of bands and does not exploit the spectral richness of the hyperspectral data. In this paper, we propose to use both approaches, and then fuse them. The data are first pre- processed to extract some spatial information. Using Support Vector Machines (SVMs), the data are classified. Finally, according to the property of SVMs outputs, we propose to fuse the results using three different operators. Results are presented on real hyperspectral data from urban area. The proposed approach is positively compared to the results obtained by each of the classifiers used separately.
Joint Reconstruction and Anomaly Detection From Compressive Hyperspectral Images Using Mahalanobis Distance-Regularized Tensor RPCA

Anomaly detection plays an important role in remotely sensed hyperspectral image (HSI) processing. Recently, compressive sensing technology has been widely used in hyperspectral imaging. However, the reconstruction from compressive HSI and detection are commonly completed independently, which will reduce the processing’s efficiency and accuracy. In this paper, we propose a framework for hyperspectral compressive sensing with anomaly detection which reconstruct the HSI and detect the anomalies simultaneously. In the proposed method, the HSI is composed of the background and anomaly parts in the tensor robust principal component analysis model. To characterize the low-dimensional structure of the background, a novel tensor nuclear norm is used to constrain the background tensor. As the anomaly part is formed by a few anomalous spectra, the anomaly part is assumed to be a tuber-wise sparse tensor. In addition, to enhance the separation of the background and anomaly, we minimize the sum of Mahalanobis distance of the background pixels. Experiments on four HSIs demonstrate that the proposed method outperforms several state-of-the-art methods on both reconstruction and anomaly detection accuracies.
Color names learning using convolutional neural networks

In this paper, we propose a two-stage CNN-based framework to learn color names from web images, aiming to predict color names for tiny image patches. To deal with the noisy labels widespread in web images, we propose a self-supervised CNN (SS-CNN) model in the first stage. The SS-CNN model is trained on image patches with their own color histograms as supervision information. Thus its outputs are able to reflect the color characteristics of images without the influence of the noisy labels. In the second stage, we finetune the SS-CNN model to learn the mapping from image patches to color names, where the patch labels are inherited from its father images. Besides, sample selection is imported iteratively in turns with the finetuning process, which helps filtering out some noisy samples and further improves the model accuracy. Our model shows high representation ability to colors and achieves better performance of color naming compared with the state-of-the-art methods.
Spatiotemporal Group Context for Pedestrian Counting

Pedestrian counting has been a challenging topic, especially in video surveillance, for a long time due to the view variations, scale changes, and spatial occlusions. While most of the previous approaches try to count people within one frame, our approach addresses this problem with a group context model, which is to segment individuals into groups and model the spatiotemporal relationships between them. With the basic definitions of the group state, group event, and group relative, a group correspondence matrix is built to model the bidirectional correspondences between the groups in two consecutive frames. Then, a group context is modeled with a sequence of context masks, which encodes not only the spatiotemporal changes within a group, but also the historical relevance and spatial dependency between different groups. Finally, we assemble context masks from multiple frames and formulate the problem of pedestrian counting as a joint maximum a posteriori problem. Markov-chain Monte Carlo is utilized to search for an optimal configuration set to match the group context model. Comprehensive experiments on the PETS2009 data set and UCSD pedestrian data set show the promising performance of the proposed approach.
A Robust Method for TV Logo Tracking in Video Streams

Most broadcast stations rely on TV logos to claim video content ownership or visually distinguish the broadcast from the interrupting commercial block. Detecting and tracking a TV logo is of interest to TV commercial skipping applications and logo-based broadcasting surveillance (abnormal signal is accompanied by logo absence). Pixel-wise difference computing within predetermined logo regions cannot address semi-transparent TV logos well for the blending effects of a logo itself and inconstant background images. Edge-based template matching is weak for semi-transparent ones when incomplete edges appear. In this paper we present a more robust approach to detect and track TV logos in video streams on the basis of multispectral images gradient. Instead of single frame based detection, our approach makes use of the temporal correlation of multiple consecutive frames. Since it is difficult to manually delineate logos of irregular shape, an adaptive threshold is applied to the gradient image in subpixel space to extract the logo mask. TV logo tracking is finally carried out by matching the masked region with a known template. An extensive comparison experiment has shown our proposed algorithm outperforms traditional methods such as frame difference, single frame-based edge matching. Our experimental dataset comes from part of TRECVID2005 news corpus and several Chinese TV channels with challenging TV logos
Object-centered narratives for video surveillance

Effective video presentation and summarization techniques are critical for fast browsing of video content. In this paper, we propose a novel presentation approach to vividly depict the moving process of a specific object in a surveillance video, which aims at effectively summarizing video content by a static image named narrative. Firstly, the object of interest is extracted and segmented from the video to form a spatio-temporal object tube. Then three criteria are proposed to select the most representative objects from this tube. We formulate the object selecting process as an energy minimization problem, in which each energy term measures a corresponding criterion cost. We maximally preserve the changes of appearance and behavior while remove other redundant content as much as possible. Finally, the selected representative objects are stitched to the background image by Poisson editing. Experimental results show the promise of the proposed approach.
Weighted Part Context Learning for Visual Tracking

Context information is widely used in computer vision for tracking arbitrary objects. Most of the existing studies focus on how to distinguish the object of interest from background or how to use keypoint-based supporters as their auxiliary information to assist them in tracking. However, in most cases, how to discover and represent both the intrinsic properties inside the object and the surrounding context is still an open problem. In this paper, we propose a unified context learning framework that can effectively capture spatiotemporal relations, prior knowledge, and motion consistency to enhance tracker's performance. The proposed weighted part context tracker (WPCT) consists of an appearance model, an internal relation model, and a context relation model. The appearance model represents the appearances of the object and the parts. The internal relation model utilizes the parts inside the object to directly describe the spatiotemporal structure property, while the context relation model takes advantage of the latent intersection between the object and background regions. Then, the three models are embedded in a max-margin structured learning framework. Furthermore, prior label distribution is added, which can effectively exploit the spatial prior knowledge for learning the classifier and inferring the object state in the tracking process. Meanwhile, we define online update functions to decide when to update WPCT, as well as how to reweight the parts. Extensive experiments and comparisons with the state of the arts demonstrate the effectiveness of the proposed method.
A Multimodal Scheme for Program Segmentation and Representation in Broadcast Video Streams

With the advance of digital video recording and playback systems, the request for efficiently managing recorded TV video programs is evident so that users can readily locate and browse their favorite programs. In this paper, we propose a multimodal scheme to segment and represent TV video streams. The scheme aims to recover the temporal and structural characteristics of TV programs with visual, auditory, and textual information. In terms of visual cues, we develop a novel concept named program-oriented informative images (POIM) to identify the candidate points correlated with the boundaries of individual programs. For audio cues, a multiscale Kullback-Leibler (K-L) distance is proposed to locate audio scene changes (ASC), and accordingly ASC is aligned with video scene changes to represent candidate boundaries of programs. In addition, latent semantic analysis (LSA) is adopted to calculate the textual content similarity (TCS) between shots to model the inter-program similarity and intra-program dissimilarity in terms of speech content. Finally, we fuse the multimodal features of POIM, ASC, and TCS to detect the boundaries of programs including individual commercials (spots). Towards effective program guide and attracting content browsing, we propose a multimodal representation of individual programs by using POIM images, key frames, and textual keywords in a summarization manner. Extensive experiments are carried out over an open benchmarking dataset TRECVID 2005 corpus and promising results have been achieved. Compared with the electronic program guide (EPG), our solution provides a more generic approach to determine the exact boundaries of diverse TV programs even including dramatic spots.
Pixelwise Deep Sequence Learning for Moving Object Detection

Moving object detection is an essential, well-studied but still open problem in computer vision and plays a fundamental role in many applications. Traditional approaches usually reconstruct background images with hand-crafted visual features, such as color, texture, and edge. Due to lack of prior knowledge or semantic information, it is difficult to deal with complicated and rapid changing scenes. To exploit the temporal structure of the pixel-level semantic information, in this paper, we propose an end-to-end deep sequence learning architecture for moving object detection. First, the video sequences are input into a deep convolutional encoder–decoder network for extracting pixel-wise semantic features. Then, to exploit the temporal context, we propose a novel attention long short-term memory (Attention ConvLSTM) to model pixelwise changes over time. A spatial transformer network and a conditional random field layer are finally appended to reduce the sensitivity to camera motion and smooth the foreground boundaries. A multi-task loss is proposed to jointly optimization for frame-based classification and temporal prediction in an end-to-end network. Experimental results on CDnet 2014 and LASIESTA show 12.15% and 16.71% improvement to the state of the art, respectively.
Classification Related Manifold Dimension Estimation with Restricted Boltzmann Machine

To handle high dimensional variables in real world, especially multimedia data, dimension reduction techniques provide effective solutions for feature selection which makes the problem easy to deal in a lower dimension subspace. However, the primary problem with traditional dimension reduction method is to estimate intrinsic dimension of manifold supporting the raw data. Since all existing approaches of dimension reduction need to set the target dimension first. And for task of classification, the dimension we need maybe different from the intrinsic one, which means feature with intrinsic dimension may offer too much information for the classification task. In this paper, we propose a method to estimate classification related dimension with the help of RBM (Restricted Boltzmann Machine) and SVM classifiers. RBM is used for dimension reduction by mapping raw data to a low dimensional hidden space, and SVM classifier is used to test information preserving ability of this hidden space. An optimal dimension is selected as the minimum one that preserves all the classification related information of novel vectors. Further, a novel initialization strategy is proposed to speed up the training of RBM. These new methods are with low time consumption and memory cost compared to many other approaches of dimension estimation. Experiments and comparisons on several synthetic and realistic datasets show the superiority of the proposed method.
DenseTracker: A multi-task dense network for visual tracking

How to track an arbitrary object in video is one of the main challenges in computer vision, and it has been studied for decades. Based on hand-crafted features, traditional trackers show poor discriminability for complex changes of object appearance. Recently, some trackers based on convolutional neural network (CNN) have shown some promising results by exploiting the rich convolutional features. In this paper, we propose a novel DenseTracker based on a mutli-task dense convolutional network. To learn a more compact and discriminative representation, we adopt a dense block structure to ensemble features from different layers. Then a multitask loss is designed to accurately predict the object position and scale by joint learning of box regression and pair-wise similarity. Furtherly, the DenseTracker is trained end-to-end on large-scale datasets including ImageNet Video (VID) and ALOV300++. The DenseTracker runs in 25 fps on GPU and achieves the state-of-the-art performance on two public benchmarks of OTB50 and VOT2016.
Global Trajectory Construction across Multi-cameras via Graph Matching

Behavior analysis across multi-cameras becomes more and more popular with the rapid development of camera network in video surveillance. In this paper, we propose a novel unsupervised graph matching framework to associate trajectories across partially overlapping cameras. Firstly, trajectory extraction is based on object extraction and tracking and is followed by a homographic projection to a mosaic-plane. And we extract appearance and spatio-temporal features for trajectory description. Then a robust graph matching algorithm based on reweighted random walk is adopted for trajectory association. The association is formulated as node ranking and selection on an association graph whose nodes represent candidate correspondences of trajectories. Finally, the pairs of corresponding trajectories in overlapping regions are fused by an adaptive averaging scheme, in which trajectories with more observations and longer length is given higher weight. Experiments and comparison on real scenarios demonstrate the effectiveness of the proposed approach.
Learning local features for object categorization

In this paper, for every local feature, we propose to learn its similar local features across all positive images, instead of using heuristic distance as similarity measure. Specifically, Multiple Instance Learning (MIL) is employed to simultaneously determine the similar points of a local feature and learn its corresponding discriminative function which can be regarded as some kind of similarity measure. For each local feature, a weak learner is constructed based on such similarity measure. Then AdaBoost selects the most discriminative local features and combines them to form a strong classifier. Experimental results show encouraging performance of our method.
Learning Semantic Motion Patterns for Dynamic Scenes by Improved Sparse Topical Coding

With the proliferation of cameras in public areas, it becomes increasingly desirable to develop fully automated surveillance and monitoring systems. In this paper, we propose a novel unsupervised approach to automatically explore motion patterns occurring in dynamic scenes under an improved sparse topical coding (STC) framework. Given an input video with a fixed camera, we first segment the whole video into a sequence of clips (documents) without overlapping. Optical flow features are extracted from each pair of consecutive frames, and quantized into discrete visual words. Then the video is represented by a word-document hierarchical topic model through a generative process. Finally, an improved sparse topical coding approach is proposed for model learning. The semantic motion patterns (latent topics) are learned automatically and each video clip is represented as a weighted summation of these patterns with only a few nonzero coefficients. The proposed approach is purely data-driven and scene independent (not an object-class specific), which make it suitable for very large range of scenarios. Experiments demonstrate that our approach outperforms the state-of-the art technologies in dynamic scene analysis.
Semantic Web-Based Personalized Recommendation System of Courses Knowledge Research

According to personalized service in teaching system, this paper proposes curriculum resources personalized recommendation algorithm based on semantic web technology. First, we get a collection of curriculum resources of interests in terms of the user evaluation and user browsing behavior, and then based on the relationship between the concept in the domain ontology, calculate semantic similarity between core concepts of different user evaluation, and finally according to the similarity decide the similarity of user preferences interests, find the nearest neighbors with similar interests, in order to achieve learning resources personalized recommendations. Combination of ontology model of “compile theory “course knowledge, we design and implement personalized learning recommendation system.