Timely prediction of a patient’s intention to exit the bed is critical for fall prevention but remains under-explored in real-world care facilities. Existing solutions rely on wearable sensors, cameras, pressure mats, or vibration sensors. However, these existing solutions may raise privacy concerns, incur high hardware costs, require extensive data annotation, and are sometimes noise-sensitive. These systems are typically validated in small laboratory studies or simulated environments, which lack the scale and diversity needed to assess real-world generalization. In this study, we propose a novel bed-exit intention prediction system based on a single load sensor installed under one bed leg and a Transformer-based prediction model, BEDFormer. BEDFormer introduces a Time‑aware De‑stationary Attention mechanism that embeds relative temporal information and dynamically adapts to the non-stationarity of load sensor signals over time. This prediction model can be trained with either annotated or quick heuristic labels for rapid deployment. We collected six months of bed-exit data from 95 beds in a care facility and demonstrated that BEDFormer outperforms recent state‑of‑the‑art time series baselines on all major metrics. Additionally, in a 19‑day field test at a senior care facility, the system achieved an average F1 score of 0.92 across nine residents, confirming strong cross‑site robustness. By turning an inexpensive, privacy‑preserving load sensor into a reliable early‑warning device, BEDFormer lowers the barrier to proactive fall prevention in healthcare settings.

Images affected by the same distortion type and level usually have consistent statistical characteristics, while different distortions exhibit significant discriminability. Inspired by this observation, this paper proposes a Degradation-aware Contrast Learning (DCL) framework to explicitly model degradation properties for Blind Image Quality Assessment (BIQA). First, a Latent Degradation Space (LDS) is constructed via self-supervised contrastive learning to effectively capture degradation features from distorted images. Then, deep semantic features are extracted using a pre-trained model and fused with the degradation features to provide complementary bias information. Finally, the fused features are mapped to perceptual quality scores by a regression model. The experimental results show that the proposed method outperforms existing state-of-the-art BIQA methods in terms of prediction accuracy, robustness, and generalization ability.

Phase unwrapping is a crucial step in deriving deformation from interferometric synthetic aperture radar data, yet challenges such as discontinuous noise in low-coherence areas and random sensor noise can significantly compromise reconstruction accuracy and efficiency. Existing methods often struggle under noisy conditions and exhibit slower processing times. To overcome these limitations, this paper introduces Phaseformer, a transformer-based model designed to predict the wrap count at each pixel directly from wrapped phase maps. Due to the limited size of the real-world dataset, a simulated dataset with diverse noise levels was developed to train the model. Phaseformer achieved the lowest RMSE of 1.88 rad, a success ratio of 95.6%, and a runtime of 0.01 s per image, outperforming both state-of-the-art methods and traditional methods. For real-world scenarios, unwrapped phase results were integrated into a post-processing workflow using MintPy to derive time-series deformation. Interferograms from Hawaii and Mexico City, generated using Sentinel-1 data and validated with GPS ground truth, revealed consistent deformation rates with minimal loop closure errors. These results highlight Phaseformer’s potential for accurate and efficient phase unwrapping in complex, real-world applications.

In intelligent fault diagnosis, fault severity classification with class imbalance remains a tremendous challenge. To simultaneously consider relative natural order in fault severity and class imbalance, we propose the adaptive ordinal sample-weighted meta residual network (AOSW-MRN). The AOSW-MRN model uses a weighting network and a meta-model cloned from the residual network to create a nonlinear weighted mapping. It adaptively learns sample weights from a balanced and clean-label meta-dataset, training a model robust to imbalance and ordinal relationships. We validate its effectiveness in two real-world case studies with different imbalance rates. Experimental results demonstrate that our model outperforms several existing Start-of-the-Art models regardless of classification and regression performance since it considers the ordinality of samples in the feature space.

Industrial asset management (IAM) is crucial for the sustainability and efficiency of industries that depend on significant infrastructure, especially pipelines. Pipelines are vital assets in the global energy supply chain, transporting oil, natural gas, and chemical products, and their maintenance is essential to prevent severe environmental and economic consequences. However, current methods such as manual visual inspections are limited by their invasiveness, the requirement for periodic shutdowns, and a lack of real-time accuracy. These limitations present substantial challenges to effective IAM. This paper introduces an innovative digital twin ecosystem integrated with information and communication technology to enhance IAM for pipelines. This ecosystem creates a dynamic, interactive digital twin that accurately reflects the physical state of pipelines, bolstered by real-time data transmission from sensors. The ecosystem comprises physical pipelines equipped with sensors, a comprehensive data knowledge library that records and updates damage information, a virtual pipeline twin, and an interactive platform that facilitates detailed visualization and interaction. Through a detailed case study of pipeline damage detection on cracks and corrosion using visual imaging techniques, this paper demonstrates enhanced results and visualizations compared to existing methods. The observed damage features sharper contrasts, higher resolution, and clearer boundaries in affected areas, significantly improving the accuracy of damage localization. Additionally, the relative accuracy of the calculated damage stress intensity factor by the virtual twin model reaches 95%. In summary, the capabilities for real-time, remote interaction and comprehensive visualization within the digital twin ecosystem significantly enhance the management efficiency of digital and intelligent pipeline IAM.

This study presents a framework for distributed predictive maintenance using the BaSyx platform and edge computing devices. By integrating predictive maintenance algorithms, the system can estimate remaining useful life, detect early faults, and identify anomalies without prior failure data. The real-time processing capabilities of edge devices, combined with a local server, aid in immediate data integration and decision-making to optimize maintenance scheduling and improve operational reliability. While vehicles are used as a specific example in this research, the proposed framework is adaptable and applicable to predictive maintenance across various industrial assets. This study provides a baseline for advanced predictive maintenance strategies.

The frequency of the free induction decay (FID) signal induced from an Overhauser magnetometer sensor is proportional to the magnetic field to be measured. Due to the low initial signal-to-noise ratio (SNR), sensor tuning is necessary to suppress the noise and improve the frequency estimation accuracy. To improve the tuning performance in complex strong-disturbance environments, this study introduces a novel method using higher-order singular value tensor decomposition (HOSVTD) and Fourier synchrosqueezing transform (FSST), namely HOSVTD-FSST. First, multiple FID signals are obtained using an equal delay multichannel acquisition strategy to establish a deeper, more intrinsic correlation attribute. Second, matrix segmentation is applied to construct the signals into a higher-order tensor for singular value computation, and the CANDECOMP/PARAFAC (CP) decomposition is fused to obtain a low-noise FID. Third, the FSST is employed to analyze the low-noise signal to extract the time-frequency ridges to capture the tuning frequency. Finally, the HOSVTD-FSST is compared with numerous commonly used methods. The experimental results demonstrate that under the presence of spike noise and with the SNR less than −20 dB, the frequency tuning deviations of the commonly used methods are up to 100 Hz, while that of the HOSVTD-FSST is within 5 Hz, which verifies that the HOSVTD-FSST can significantly enhance the sensor tuning accuracy in complex strong-disturbance conditions.

Convolutional neural network (CNN)-based fault detection approaches based on multisource signals have attracted increasing interest from the research community and industrial practices, thanks to the powerful feature representation capability of CNN and the rapid development of sensor technology. Various strategies have been applied in existing CNN-based diagnostic models to learn features from 1-D real-valued multivariate data. However, the distribution gap and the intrinsic correlations among multisource mechanical signals during the learning process have been rarely considered, which may lead to suboptimal fault identification results. To tackle this issue, this article proposes a cross-modal fusion convolutional neural network (CMFCNN) for mechanical fault diagnosis, which performs modality-specific and cross-modal feature representation on multisource data. Specifically, CMFCNN adopts two parallel modality-specific networks and a cross-modal knowledge-sharing network to fully explore independent and shared features from the multisource mechanical signals. To achieve effective feature propagation and fusion, a cross-modal fusion module is introduced to integrate cross-modal features and pass the fused information to the next layer. Moreover, to alleviate overfitting and achieve a better diagnostic performance of the framework, an online soft-label training algorithm is adopted in the CMFCNN training phase. Extensive experimental results on the cylindrical rolling bearing dataset and the planetary gearbox dataset validate that the proposed CMFCNN outperforms seven state-of-the-art methods significantly, especially under strong noise conditions.

It has become a common practice for many perceptual systems to integrate information from multiple sensors to improve the accuracy of object detection. For example, autonomous vehicles use visible light, and infrared (IR) information to ensure that the car can cope with complex weather conditions. However, the accuracy of the algorithm is usually a trade-off between the computational complexity and memory consumption. In this study, we evaluate the performance and complexity of different fusion operators in multi-modal object detection tasks. On top of that, a Poolformer-based fusion operator (PoolFuser) is proposed to enhance the accuracy of detecting targets without compromising the efficiency of the detection framework.

In the field of magnetic anomaly detection (MAD), the anomaly signal is easily submerged by ambient electromagnetic interference. Though the existing noise suppression methods can effectively improve the signal-to-noise ratio (SNR), there are still some intractable problems, such as signal distortion and boundary blur. To solve these problems, a novel MAD method based on structured low rank (SLR) and total variation (TV) regularization constraints is proposed in this letter. The noise suppression performance is improved by leveraging the structured low rankness of the signal. To preserve clean boundaries of the anomalies, an anisotropic TV regularization constraint is employed in the approach. Comparing the SLR-TV method with four state-of-the-art methods with extensive field tests, the results demonstrate that the proposed SLR-TV method achieves the greatest SNR improvement by about 63.24% and the best structural similarity (SSIM) improvement by about 53.02% over other methods in the range from −40 to 0 dB, showing the utility and high fidelity of the proposed framework in low SNR.

Recent advances in data-driven methods have significantly promoted intelligent fault diagnostics for varied industrial applications. However, due to the limitations of machine fault data and the varied scenarios in the context of industrial working conditions, existing diagnostic models can hardly achieve satisfactory results. In this article, we propose a domain discrepancy-guided contrastive feature learning framework for few-shot fault diagnosis under varied working conditions. Unlike the conventional contrastive learning paradigm using manually augmented data, a sample pairs construction is implemented based on the differences between domain distributions for data acquired under different working conditions. The similarity contrast learns the domain-invariant features from a small number of sample pairs. The learned fault features can then be used for fault identification without parameter fine-tuning. In two case studies, we validated the performance of the proposed framework with small training samples under varying speeds, loads, and significant noises. Compared with the state-of-the-art methods, the proposed solution achieved higher diagnostic accuracy for the targeted applications.

The rotor-bearing system is widely used in various high-end electro-hydraulic equipment, which provides specific support, rotation, and other integral functions. However, the fluctuating working conditions of the rotor-bearing system will cause more significant disordered fluctuations in the measured signals. This article proposes a new algorithm called multiscale deep graph convolutional networks (MS-DGCNs) to alleviate this problem. The designed MS-DGCNs algorithm combines a new multiscale intra-class fine coarse-grained processing and multiscale graph convolution kernels. Accordingly, an intelligent fault diagnosis method based on MS-DGCNs for the rotor-bearing system under fluctuating conditions is designed to learn more feature representations and accuracy. First, a sliding window is employed to divide the collected vibration signals into a series of subsignals. The multiscale signal processing is performed to obtain different degrees of the fine-coarse time series. Then, a graph convolution with the multiscale convolution kernel is designed. Finally, the soft-max classifier is combined for intelligent fault diagnosis. The experimental results of the double-span rotor-bearing system under fluctuating conditions well demonstrate that the method has the higher accuracy and generalization.

Traffic lights optimization is one of the principal components to lessen the traffic flow and travel time in an urban area. The present article seeks to introduce a novel procedure to design the traffic lights in a city using evolutionary-based optimization algorithms in combination with an ontology-based driving behavior simulation framework. Accordingly, an ontology-based knowledge base is introduced to provide a machine-understandable knowledge of roads and intersections, traffic rules, and driving behaviors. Then, a simulation environment is developed to inspect car behavior in real time. To optimize the traffic lights, a sine-based equation was defined for each traffic light, and the total travel time of the vehicles was considered as the cost function in the optimization algorithm. The optimization was performed with 5, 10, 15, 20, 25, and 30 vehicles in the urban areas. Based on the results, in contrast to uncontrolled intersections without traffic lights, optimized traffic lights can significantly contribute to total travel time-saving. To conclude, due to an escalation in the number of vehicles, the significance of optimized traffic lights has encountered an increase, and unoptimized traffic lights could increase total travel time even more than a city deprived of any traffic light.

The industrial gearboxes usually work in harsh and variable conditions, which results in partial failure of gears or bearings. Accordingly, the continuous irregular fluctuations of gearbox under variable conditions maybe increase the intraclass difference and reduce the interclass difference for the monitored samples. To this end, a new intelligent fault diagnosis method of gearbox based on adaptive intraclass and interclass convolutional neural network (AIICNN) under variable working conditions is proposed. The core of the proposed algorithm is to apply the designed intraclass and interclass constraints to improve the distribution differences of samples. Meanwhile, the adaptive activation function is added into the 1-D convolutional neural network (1dCNN) to enlarge the heterogeneous distance and narrow the homogeneous distance of samples. Specifically, the training sample subset with intraclass and interclass spacing fluctuations under variable conditions is first converted into frequency domain through the fast Fourier transform (FFT), and the designed AIICNN algorithm is employed for model training. Afterward, the testing subset is provided to the trained AIICNN algorithm for fault diagnosis. The experimental data of the planetary gearbox test rig verify the feasibility of the proposed diagnosis method and algorithm. Compared with other methods, this method can eliminate the difference of sample distribution under variable conditions and improve its diagnostic generalization.

Fossil energy products such as liquefied natural gas (LNG) are among Canada's most important exports. Canadian engineers devote themselves to constructing visual surveillance systems for detecting potential LNG emissions in energy facilities. Beyond the previous infrared (IR) surveillance system, in this paper, a multimodal fusion-based LNG detection (MFLNGD) framework is proposed to enhance the detection quality by the integration of IR and visible (VI) cameras. Besides, a Fourier transformer is developed to fuse IR and VI features better. The experimental results suggest the effectiveness of the proposed framework.

Recently the machine learning-enabled modeling technology has become a powerful tool to develop data-driven models for explaining, predicting, and describing system behaviors. In particular, it has become a key tool for developing data-driven models for emerging digital twin development which demands the living models for simulating system behaviors. However, such data-driven models carry a fatal deficiency: once the operational environments changed, the model may hardly work well or even becomes useless. This paper attempts to address this issue by proposing to apply transfer learning techniques to develop lifetime robust models for real-world applications. After laying out problems and the reasons of model performance degradation, this paper presents a framework for developing lifetime predictive models for digital twin. A show case from our on-going research project along with the preliminary results demonstrates the feasibility and usefulness of the proposed predictive modeling methods.

Traditional image fusion focuses on selecting an effective decomposition approach to extract representative features from the source image and attempts to find appropriate fusion rules to merge extracted features respectively. However, the existing image decomposition tools are mostly based on kernels or global energy-optimized functions limiting the performance of the wide range of image contents. This paper proposes a novel infrared and visible image fusion method based on deep decomposition network and saliency analysis (named DDNSA). First, the modified residual dense network (MRDN) is trained with a publicly available dataset to learn the decomposition process. Second, the structure and texture features of source images are separated by the trained decomposition network. Then, according to the characteristics of the above features, we construct the combination of local and global saliency maps by using stacked sparse autoencoder and visual saliency mechanism to fuse the structural features. Besides, we propose a bi-direction edge-strength fusion strategy for merging the texture features. Finally, the resultant image is reconstructed by combining the fused structure and texture features. The experimental results confirm that our proposed method outperforms the state-of-the-art methods in both visual perception and objective evaluation.

Although the importance of remaining useful life (RUL) prediction is widely recognized in industries, its implementation in real scenarios is highly restricted by the complexity of the degradation mechanism, uncertainty of machinery, and insufficiency of prior knowledge. To address such a challenge, this article proposes a model-based framework, which has the capability to integrate multiple predictive models via a probabilistic mechanism. When a new observation is fed into each predictive model, the posterior distribution of each model will be updated via Bayesian inference. Then, a grid-sampling strategy is applied to their posterior distributions for identifying the “peak” and “profile,” which are used for RUL prediction and reliability assessment, respectively. The effectiveness of this framework is validated with the experiments on a set of steel tension specimens. Theoretical interpretations and comparative studies demonstrate the superiority of the proposed framework. Besides, the proposed framework can not only reduce human workload on trivial parameter setting but also be effective with insufficient prior knowledge, making the intelligent RUL prediction easier.

Sewer networks and water distribution systems are among the most valuable and critical urban assets for a community. These systems have their respective time span to provide continuous service to the residents. Hence, it is paramount to assess the condition of sewer and water pipelines to ensure sustainable, reliable, and cost-effective transportation of sewerage and water supply. The assessment is usually done by the inspection robots, which are equipped with machine vision systems and/or sensors. The inspection robots acquire the inspection data, and the operators then conduct the survey of the captured video and/or sensory data to interpret the results. Nowadays, automated solutions are being adopted by industry to achieve an accurate and efficient assessment. This article surveys the state of the art of the automated vision systems, which are employed for condition assessment of sewer and water pipelines, and identifies the challenges for future research. The following areas are highlighted in this survey: 1) the typical types of the faults and failures, which include the concept and definition of the sewer and water pipelines; 2) the inspection systems, e.g., robotic platforms for sewer and water pipeline inspection; 3) the machine vision systems for fault detection; 4) the computational frameworks for condition assessment; and 5) the challenges and suggestions for future research. This article summarizes the current state of automation in the machine vision technology for condition assessment (both hardware and software perspectives) of sewer and water pipelines and also provides a reference for researchers to further advance the technology in this field.Note to Practitioners—The motivation behind this article was the current challenges and the open issues of the vision system for the condition assessment of sewer and water pipelines. This article presents detailed reviews of the state-of-the-art of the vision system (both hardware and software) and discusses the existing problems. This survey aims to help engineers and researchers to resolve and improve the problems and extend the field of the existing automated frameworks. This article is organized in the form of a survey so that researchers can benefit and get all the useful information at a glance. This article provides a rigorous overview of typical faults, inspection robots, visual techniques, and automated frameworks for the condition assessment and discusses the challenges and future research directions. The objective of this article is to create a baseline for the readers to acquaint themselves with the state of the art and advance the research in this field.

Detection of the liquefied natural gas (LNG) leakage attracts increasing attention for preventing environments and governments from severe pollution and economic loss. Existing frameworks take advantage of stationary surveillance thermal cameras to detect the LNG leakage, which comprises background subtraction and leakage classification. However, these methods are limited in rural areas due to the lack of sensitivity and accuracy. In this article, a generalized framework, i.e., tensor-based leakage detection (TBLD), is proposed to detect LNG leakage in the rural area from surveillance thermal cameras. First, the proposed TBLD takes advantage of tensor factorization to fuse thermal image and corresponding gradient maps for improving sensitivity. Additionally, a finite-state-machine is designed to maintain leakage foreground along with the video streaming. The experiments demonstrate the robust performance of TBLD in the background subtraction stage. Second, multiple classification techniques are explored in the leakage classification stage. The results suggest that the TBLD can accurately detect the LNG leakage by applying 50 layers of residual networks (ResNet50). Finally, compared with contemporary frameworks, the TBLD has consistently improved performance concerning the different distances of LNG leakage. The experimental results demonstrate the effectiveness of the proposed TBLD, which also shows the great potential of TBLD in future industrial applications.

The labeled monitoring data collected from the electromechanical system is limited in the real industries; traditional intelligent fault diagnosis methods cannot achieve satisfactory accurate diagnosis results. To deal with this problem, an intelligent fault diagnosis method for electromechanical system based on a new semisupervised graph convolution deep belief network algorithm is proposed in this article. Specifically, the labeled and unlabeled samples are first employed to design a new adaptive local graph learning method for constructing the graph neighbor relationship. Meanwhile, the labeled samples are applied to describe the discriminative structure information of data via the latest circle loss. Finally, the local and discriminative objective functions are reconstructed under the semisupervised learning framework. The experimental results from the motor-bearing system demonstrate that the method can achieve 98.66 % accuracy with only 10 % of training labeled data, which indicates that it is a promising semisupervised intelligent fault diagnosis method.

Context enhancement is critical for the environmental perception in night vision applications, especially for the dark night situation without sufficient illumination. In this article, we propose a thermal image translation method, which can translate thermal/infrared (IR) images into color visible (VI) images, called IR2VI. The IR2VI consists of two cascaded steps: translation from nighttime thermal IR images to gray-scale visible images (GVI), which is called IR-GVI; and the translation from GVI to color visible images (CVI), which is known as GVI-CVI in this article. For the first step, we develop the Texture-Net, a novel unsupervised image translation neural network based on generative adversarial networks. Texture-Net can learn the intrinsic characteristics from the GVI and integrate them into the IR image. In comparison with the state-of-the-art unsupervised image translation methods, the proposed Texture-Net is able to address some common challenges, e.g., incorrect mapping and lack of fine details, with a structure connection module and a region-of-interest focal loss. For the second step, we investigated the state-of-the-art gray-scale image colorization methods and integrate the deep convolutional neural network into the IR2VI framework. The results of the comprehensive evaluation experiments demonstrate the effectiveness of the proposed IR2VI image translation method. This solution will contribute to the environmental perception and understanding in varied night vision applications.

There have been many advances in image fusion to support multi-modal, multi-perspective, and multi-focal day-night robust surveillance. Contextual analysis of multi-sensor exploitation supports many information fusion systems for target tracking, situation awareness, and scene understanding. This paper highlights an example for electro-optical and infrared image fusion analysis and colorization in support of simultaneous tracking and identification for physics-based and human-derived information fusion (PHIF). The results provide an ongoing discussion and analysis of the importance of context as both a source to guide information fusion systems (e.g., sensor mode selection), but also the need to be able to provide users with robust systems over context changes (e.g., variations in illumination).

Non-intrusive detection is critical to protecting the integrity of pipelines. Based on the wireless sensor network, a novel leak monitoring system, composed of a computer center, a coordinator and wireless non-intrusive sensing nodes, is proposed for pipelines of closed spaces in this paper. The wireless nonintrusive sensing node with convenient installation and disassembly on the pipeline wall is designed. The proposed system can achieve signal synchronous sampling of all wireless non-intrusive sensing nodes by the coordinator wirelessly broadcasting the time information from its GPS to them, which is significant to guarantee the accuracy of the leak location. Based on the delay cross-correlation analysis, a leak location method is presented for multiple sensors. And experimental results demonstrate that the proposed system can accurately detect and locate pipeline leaks.

Recent advances in image super-resolution (SR) explored the power of deep learning to achieve a better reconstruction performance. However, the feedback mechanism, which commonly exists in human visual system, has not been fully exploited in existing deep learning based image SR methods. In this paper, we propose an image super-resolution feedback network (SRFBN) to refine low-level representations with high-level information. Specifically, we use hidden states in a recurrent neural network (RNN) with constraints to achieve such feedback manner. A feedback block is designed to handle the feedback connections and to generate powerful high-level representations. The proposed SRFBN comes with a strong early reconstruction ability and can create the final high-resolution image step by step. In addition, we introduce a curriculum learning strategy to make the network well suitable for more complicated tasks, where the low-resolution images are corrupted by multiple types of degradation. Extensive experimental results demonstrate the superiority of the proposed SRFBN in comparison with the state-of-the-art methods. Code is avaliable at https://github.com/Paper99/SRFBN_CVPR19.

The integrity of geomagnetic data is a critical factor in understanding the evolutionary process of Earth's magnetic field, as it provides useful information for near-surface exploration, unexploded explosive ordnance detection, and so on. Aimed to reconstruct undersampled geomagnetic data, this paper presents a geomagnetic data reconstruction approach based on machine learning techniques. The traditional linear interpolation approaches are prone to time inefficiency and high labor cost, while the proposed approach has a significant improvement. In this paper, three classic machine learning models, support vector machine, random forests, and gradient boosting were built. Besides, a deep learning algorithm, recurrent neural network, was explored to further improve the training performance. The proposed learning models were used to specify a continuous regression hyperplane from a training data. The specified regression hyperplane is a mapping of the relation between the mock-up missing data and the surrounding intact data. Afterward, the trained models, essentially the hyperplanes, were used to reconstruct the missing geomagnetic traces for validation, and they can be used for reconstructing further collected new field data. Finally, numerical experiments were derived. The results showed that the performance of our methods was more competitive in comparison with the traditional linear method, as the reconstruction accuracy was increased by approximately 10%~20%.

Making fast driving decisions at intersections is a challenging problem for improving safety of autonomous vehicles. Furthermore, representing sensor data in a machine understandable format is essential to enable vehicles to understand traffic situations. Ontologies are used to represent knowledge of sensor data for autonomous vehicles to aware traffic situations. In this paper, we introduce a fast decision making system, which utilizes only related part of the ontology-based knowledge base to make decisions at intersections. The decision making system performs real-time reasoning using traffic regulations and a part of the map information from the knowledge base.

Multisensor image fusion or pansharpening aims to sharpen a multispectral (MS) image by integrating the detail map derived from a panchromatic (Pan) image. The intensity-hue-saturation (IHS)-based methods are well adopted in pansharpening applications. However, the pansharpened MS images by IHS-based methods usually suffer from serious spectral distortions and local artifacts due to the mismatch between the estimated detail map and its ground truth. To overcome these defects, we propose a weighted least squares (WLS)-filter-based method in this letter. Different from existing IHS-based methods, the proposed method eliminates the influence of the low-frequency components of the Pan and MS images with the WLS filter. Moreover, the derived detail map is further refined based on the spectral signatures for different bands of the MS image. We test the proposed method on various satellites data; the experimental results demonstrate that the proposed method performs well in both spectral and spatial qualities.

Traditional methods for automatic recognition of container code in visual images are based on segmentation and recognition of isolated characters. However, when the segment fails to separate each character from the others, those methods will not function properly. Sometimes the container code characters are printed or arranged very closely, which makes it a challenge to isolate each character. To address this issue, a new framework for automatic container code recognition (ACCR) in visual images is proposed in this paper. In this framework, code-character regions are first located by applying a horizontal high-pass filter and scan line analysis. Then, character blocks are extracted from the code-character regions and further classified into two categories, i.e. single-character block and multi-character block. Finally, a segmentation-based approach is implemented for recognition of the characters in single-character blocks, and a hidden Markov model (HMM)-based method is proposed for the multi-character blocks. The experimental results demonstrate the effectiveness of the proposed method, which can successfully recognize the container code with closely arranged characters.

This paper proposes an image fusion algorithm based on a sparse linear equation system, which uses local extreme of high resolution image and intensity of multi-spectral image to construct the system. Based on this sparse system, the multi-scale image decomposition algorithm can be implemented. This algorithm extracts the details of the high-resolution image and integrates with the multi-spectral information to derive the fused image.

Multimodal medical image fusion, as a powerful tool for the clinical applications, has developed with the advent of various imaging modalities in medical imaging. The main motivation is to capture most relevant information from sources into a single output, which plays an important role in medical diagnosis. In this paper, a novel fusion framework is proposed for multimodal medical images based on non-subsampled contourlet transform (NSCT). The source medical images are first transformed by NSCT followed by combining low- and high-frequency components. Two different fusion rules based on phase congruency and directive contrast are proposed and used to fuse low- and high-frequency coefficients. Finally, the fused image is constructed by the inverse NSCT with all composite coefficients. Experimental results and comparative study show that the proposed fusion framework provides an effective way to enable more accurate analysis of multimodality images. Further, the applicability of the proposed framework is carried out by the three clinical examples of persons affected with Alzheimer, subacute stroke and recurrent tumor.

Comparison of image processing techniques is critically important in deciding which algorithm, method, or metric to use for enhanced image assessment. Image fusion is a popular choice for various image enhancement applications such as overlay of two image products, refinement of image resolutions for alignment, and image combination for feature extraction and target recognition. Since image fusion is used in many geospatial and night vision applications, it is important to understand these techniques and provide a comparative study of the methods. In this paper, we conduct a comparative study on 12 selected image fusion metrics over six multiresolution image fusion algorithms for two different fusion schemes and input images with distortion. The analysis can be applied to different image combination algorithms, image processing methods, and over a different choice of metrics that are of use to an image processing expert. The paper relates the results to an image quality measurement based on power spectrum and correlation analysis and serves as a summary of many contemporary techniques for objective assessment of image fusion algorithms.

Measuring image similarity is important in many applications. Different algorithms propose to compare images using pixel-based mean square error methods others use structure-based image quality index. We present, here, a new feature-based approach that utilizes image phase congruency measurement to quantify the assessment of the similarities or differences between two images