Reversible Image Research Articles

Reversible Image Watermarking Using Modified Quadratic Difference Expansion and Hybrid Optimization Technique

Reversible Image Watermarking Using Modified Quadratic Difference Expansion and Hybrid Optimization Technique

Reverse Image Search for Collage: A Novel Local Feature-Based Framework

Reverse Image Search for Collage: A Novel Local Feature-Based Framework

Geneze keltských třetin statéru tzv. hmyzího typu

The Origin of the Celtic 1/3-Staters of the So-Called Insect Type The article deals with chonology, provenance, typology and development of the reverse images of 1/3-staters of the so called insect type which had evolved from the late Bohemian issues of the Athena Alkidemos type during the pre-Stradonice Period already, and was subsequently struck simultaneously with the 1/3-staters of the so-called Muschel type with zigzag line.

Array ultrasonic guided wave spiral focusing detection method for inner damage of messenger cable in covered area

The messenger cable damage detection of catenary system is one of the important safeguard to ensure the safe operation of electrified railways. Due to the multi-layer and opposite spiral direction structure of the messenger cable, the ultrasonic guided wave dispersion curve is difficult to obtain, and the inner layer damage signal is too weak to identify. A novel array ultrasonic guided wave spiral focusing detection method is proposed for the inner layer damage of messenger cable in covered area. Firstly, the dispersion curves of ultrasonic guided waves in the messenger cable were calculated by semi-analytical finite element based on twisted coordinate system, and the multi-modal propagation characteristics were analyzed. Secondly, the path differences from guided wave array elements to inner layer were studied to get the adjustment matrix of spiral focusing. Thirdly, the inner damage information was extracted from spiral focusing signal by cross sparse representation based on dispersion dictionary, and the damage autofocus imaging was realized by bi-directional time reversal imaging. Finally, the spiral focusing enhancement effect and identification imaging effect of inner layer damage were analyzed and verified through simulation and experiments. The results show that, compared with the normal superimposed method, the damage signal indexes of sub-outer layer and the center layer are increased by 32.2% and 40.8% respectively after spiral focusing. The inner layer damage signal of the spiral focusing method has a higher recognition rate and good anti-interference ability, and the damage imaging has low sensitivity to threshold value and has no damage artifacts.

Research on noise suppression of imaging data by optimized least squares reverse time migration method

Least squares reverse time migration imaging is an imaging theory based on the accurate description of geological structures by seismic waves, which can greatly improve the detection accuracy. In the complex environment of deep region, the influence of noise on the imaging resolution of reverse time migration is particularly significant. In this paper, an optimized least squares reverse time migration imaging method with better amplitude fidelity and higher imaging accuracy is proposed. This method suppresses the noise interference by reducing the residual value between the inversion data and the actual data. The experimental results in the paper show that the optimized least squares reverse time migration can achieve high accuracy and high resolution imaging, especially in the deep region. This method is effective and feasible.

Shallow Ice‐Sheet Composite Structure Revealed by Seismic Imaging Near the West Antarctic Ice Sheet (WAIS) Divide Camp

AbstractSmall‐scale polar ice‐sheet composite structures can influence coarse‐grained climate models. For example, surface melting can hydro‐fracture the ice and may eventually lubricate the base. The drainage process will change the petrophysical properties of the subsurface and is predictable from high‐resolution seismic imaging. Ray‐based imaging methods, though limited by the approximations made, have mapped seismic velocities in 1D, but have yet to offer definitive information about the lateral heterogeneity. Here we use the wave‐equation‐based seismic imaging method to estimate shear‐wave velocities and to image an englacial reflector in 2D. We use 7‐day ambient‐noise data recorded by a linear array near the West Antarctic Ice Sheet (WAIS) Divide drilling site to perform the study. We obtain 2D vertical and horizontal shear‐wave velocity models and observe a lateral variation of the radial anisotropy along the acquisition line. The inverted velocity model is further used to estimate the thicknesses of firn‐air and firn layers. We also observe evident SH reflections and calculate the reflector image using robust zero‐offset imaging and a more precise reverse time migration imaging method. The imaged reflector is at about 1,700 m depth and is dipping to the southwest. We anticipate that a porosity change at that depth may cause this englacial seismic discontinuity near WAIS Divide. Our results demonstrate the feasibility of estimating the petrophysical properties of polar ice using seismic methods. We anticipate our work to be further used for understanding ice dynamics and thermodynamics, such as the stability of ice shelves, the retreat of the Antarctic ice sheet, and restoring the paleo‐sedimentary environment.

Fighting cheapfakes: using a digital media literacy intervention to motivate reverse search of out-of-context visual misinformation

Abstract As a significant source of misinformation, out-of-context visual misinformation refers to visuals presented in an unrelated context. This study explores whether a digital media literacy intervention that features reverse image search tools has significant effects on participants’ message credibility judgment, discernment of visual misinformation, and intention of using reverse image search tools. Data were collected from a pre-registered, web-based, between-subjects experiment (N = 905). Results revealed a significant difference on intention of using reverse search tools among three experimental conditions: active intervention that involved both knowledge and behavior, passive intervention that involved knowledge only, and a control condition. Specifically, active intervention significantly increased intention of using reverse search tools, compared to the passive intervention and the control. Neither active nor passive intervention had an effect on credibility judgment or misinformation discernment. We discuss the implications for future digital media intervention designs and journalism practice that aim to combat visual misinformation.

A mitochondria-targeted fluorescent probe for reversible recognition of sulfur dioxide/formaldehyde and its application in cell imaging

Sulfur dioxide (SO2) and formaldehyde (FA) are the main contaminants emitted by factories and their interaction could produce secondary organic aerosols which are harmful to human health. In biological systems, SO2 and FA levels are closely associated with many biological diseases. To explore the specific functions played by SO2 and FA in vivo, a new fluorescent probe ZZY that can reversibly recognize SO2 and FA in mitochondria was devised and synthesized. Probe ZZY showed advantages of great selectivity, good sensitivity and low cytotoxicity and the detection limit is 0.447 μM of SO2. In addition, probe ZZY could reversibly recognize SO2 and FA. More importantly, the probe showed good biocompatibility and could successfully perform reversible imaging of SO2 and FA in mitochondria of living cells.

스포츠 팀과 스폰서 기업의 ESG 활동이 자신 및 스폰서십 파트너의 이미지에 미치는 영향 : 쌍방향의 이미지 전이를 통한 시너지 효과를 중심으로

This study aimed to examine the effect of sport teams’ ESG on their own and their sponsors’ image and the effect of sponsors’ ESG on their own and their teams’ image. In addition, this study tried to explore the relative effectiveness of concurrent ESG of both sport teams and sponsors over sport teams’ and sponsors’ ESG on their own and their sponsorship partners’ image. For this purpose, t-tests and ANOVAs with multiple comparisons tests were conducted with scenarios that represent 5 experimental conditions(n=510). The results of this study are as follows. First, sport teams’ ESG had a positive effect on their own and their sponsors’ image through traditional, unidirectional image transfer. Second, sponsors’ ESG had a positive effect on their own and their teams’ image through reverse image transfer. Third, concurrent ESG of both sport teams and sponsors led to higher sport teams’ and sponsors’ image through bilateral image transfer than sport teams’ and sponsors’ ESG. These findings provide both sport marketers and sponsor marketers with insight into how they develop ESG strategies that enhance sport teams’ and sponsors’ image in sport sponsorship.

Developing a Translational Platform for Therapeutic Delivery of Image-Guided Ultra-Hypofractionated Prostate-Directed Radiotherapy in Orthotopic Prostate Cancer Models

<h3>Purpose/Objective(s)</h3> Prostate stereotactic body radiation therapy (SBRT) is rapidly evolving as a standard-of-care option for definitive management of localized prostate cancer. To our knowledge, there are currently no preclinical models that deliver SBRT-like treatment to orthotopic prostate tumors that reflect the precision and accuracy of clinical treatment. The objective of this study is to develop and credential a small animal radiation research platform (SAARP)-based therapeutic model of image-guided ultra-hypofractionated prostate-directed radiotherapy (RT) that is dosimetrically accurate with clinically relevant radiation doses. <h3>Materials/Methods</h3> Orthotopic prostate tumors are established following intraprostatic injection of 2 × 10⁵ PC3 tumor cells (stably expressing luciferase following lentiviral transduction) into the dorsal aspect of the prostate gland of nude mice. Serial orthotopic tumor growth is monitored with weekly bioluminescence (BLI) and Q2week MRI. Reverse-contrast cone-beam CT imaging (CBCT) is performed with intraperitoneal injection of 2mL of 60% omnipaque immediately prior to CBCT. Pre-treatment MRI is fused to CBCT to facilitate delineation of organs-at-risk (rectum, bladder, bowel bag) and target (prostate) for contouring. Individual plans (generally 4 or 5-field coplanar beam arrangement) were generated to target the prostate (SV not intentionally targeted) and avoid OAR. The SARRP was used to deliver 36.25Gy in 5 fractions of prostate-directed RT [day 30] and weekly serial BLI + MRI used to assess treatment response. <h3>Results</h3> Reverse contrast CBCT imaging +/- MR fusion was sufficient for OAR and target delineation and facilitated daily image-guidance whereas CBCT alone was insufficient. Radiation dosimetry noted a positive association between pH2AX mean fluorescence intensity (MFI) with escalating radiation doses of 0Gy, 2Gy, 8Gy and 20Gy. Preliminary DVH analysis of therapeutically irradiated orthotopic prostate tumors and adjacent OARs noted CTV prostate coverage>90%, rectumD50%<4Gy and bladderD50<4Gy in 3 of 5 serial fractions delivered. Surgically implanted intraprostatic TLD were harvested post-RT to confirm and quantify intraprostatic radiation dose received. Therapeutic response was observed with significantly lower luminescence counts in irradiated (n=13) vs non-irradiated controls (n=11) [p=0.049] and no treatment-related deaths were observed in irradiated mice. <h3>Conclusion</h3> We have developed a preclinical workflow for image-guided delivery of ultra-hypofractioned radiotherapy of orthotopic prostate tumors with ongoing optimization goals to achieve clinically relevant dose constraints and target coverage of NRG GU-005. Ongoing translational work involves DNA damage response assessment in irradiated prostate and adjacent organs-at-risks. This platform is now being explored in immunocompetent settings to better understand intraprostatic immune responses induced by prostate-directed RT.

Reverse Time Migration Imaging Using SH Shear Wave Data

In this paper, we discussed the reverse time migration imaging of compressional wave (P-wave) and horizontally polarized shear wave (SH shear wave) seismic data, together with P- and SH shear wave constrained velocity model building. In the Sanhu area in Qaidam Basin, there are large areas of gas clouds, which leads to poor P-wave seismic imaging. The P and SH shear wave seismic data of a co-located survey line with the same acquisition geometry were used to access their imaging capability using reverse time migration. We first estimated the change in P-wave and SH shear wave velocity ratio using pre-stack time migration (PSTM) for constraining the overall depth domain velocity model. Additionally, we then used an eighth-order finite difference scheme for P-wave reverse time migration on a variable grid and used the sixth-order combined compact difference (CCD) wave field simulation method for SH shear wave reverse time migration on a regular grid. The results show that the constrained velocity model produces a good match in the overall geological structure shown in the P-wave and SH shear wave reverse time migration results. However, in the gas cloud areas, SH shear wave reverse time migration has obvious imaging advantages, which can clearly image the structure inside the gas clouds.

Least-squares reverse time migration based on the viscoacoustic VTI pure qP-wave equation

With the deepening of oil and gas exploration and the increasing complexity of exploration targets, the influence of anisotropy and anelasticity of subsurface media on seismic imaging cannot be ignored. The least-squares reverse time migration is developed on the idea of linear inversion, which can effectively solve the amplitude imbalance, low resolution, and serious imaging noise problems of RTM. In this paper, based on the viscoacoustic pure qP-wave equation, the corresponding demigration operator, adjoint operator, and gradient-sensitive kernel are derived, and the least-square reverse time migration imaging algorithm of viscoacoustic pure qP-wave in VTI medium is proposed. During iterative inversion, the inverse of Hessian is approximately solved to achieve stable attenuation compensation. Finally, we verify the effectiveness and applicability of the proposed viscoacoustic VTI least-squares reverse time migration imaging algorithm through the model tests and field data. The numerical results show that the method can compensate for the amplitude loss and phase distortion caused by attenuation, and correct the anisotropy-induced misalignment of the reflection interfaces, which improves the accuracy and resolution of the imaging profile.

Ecommerce Website with Recommendation System Including Chatbot and Reverse Image Search

Abstract: In Today’s generation, it has become a need to get clear vision, prioritize and effortlessly to provide appropriate information to decrease the problem of information overload, which has created a major problem for many users using internet. Recommender systems is capable to solve this major problem by using searching technique through a huge volume of dynamically generated useful data to provide users with personalized content and services depending on their interest. Recommendation system plays an important role in the internet world and is used in many applications. Recommendation systems are of three types: 1) collaborative filtering 2) content based and 3) hybrid based approach. With the advancement of machine learning for decades, there are still numerous problems insolvable, such as image recognition and location detection, image classification, image generation, speech recognition, natural language processing and so on. In this emerging field of deep learning, the research on topic like image classification has always been the topmost traditional research to be evolved. Simultaneously, Image recognition technology is also beneficial to gradually respond in better way to the development of international indicators, and betterment the development and progress in various fields. Hence, image processing technology which is based on machine learning has always been widely used in feature image segmentation, classification and recognition, and is an important topic in various fields. It allows you to find similar products in your store in a very easy way. Let the customer find the product based on the photo. What's more, you no longer have to manually match similar products, it will be done automatically by AI algorithm. The main purpose of this project is to use the concept of a machine learning algorithm to build a Recommendation and Reverse Image Search and recognition with the help of convolutional neural networks (CNN).

A Reversible Digital Image Watermarking Technique for Integrity and Authenticity of MR Images

Digital Watermarking is the art and science of embedding information in existing digital content for Digital Rights Management (DRM) and authentication. Reversible watermarking is a class of (fragile) digital watermarking that not only authenticates multimedia data content, but also helps to maintain perfect integrity of the original multimedia “cover data”. Watermarking of digital images is a well-known technique that is widely used for securing image contents. A successful watermarking method must be accurate, reversible, resilient, and robust against various attacks. The technical revolution associated with the implementation the development of digital technologies in medicine, has led to the emergence and active development of new directions in many areas of medicine. The authenticity and integrity of medical images has to be protected. Hence in this paper a reversible digital image watermarking technique for integrity and authenticity of MR (Magnetic Resonance) images is presented. Reversible watermarking is recognized as a robust approach to confirm the integrity and authenticity of medical images and to verify that alterations can be detected and tracked back.

Reversible image watermarking algorithm based on reverse histogram translation

Reversible image watermarking algorithm based on reverse histogram translation

An enhanced reversible image steganography using distributive Tian's method

AbstractIn recent years, the concept of image encryption and data concealing has become a major area of research that significantly improves the secure communication of images with hidden data in them. The usage of the cloud has been outstanding in several aspects so as its security to ensure privacy over the data stored in it. The concept of reversible image steganography is one such stream where the cloud users are highly relying upon the privacy of the data, they store in the cloud servers. The reversible image steganography has the potential to recover the original image from the stego‐image once the embedded data is extracted. In this research work, an effective distributive Tian's method is proposed to embed the data onto an encrypted image without degrading the performance of the encrypted image. The cross‐verification of lossless image steganography can be identified when the original image is getting extracted from the encrypted image. The result of the proposed method ensures that the distributive Tian's method outperforms the recent state‐of‐art methods. The proposed method is deployed onto six different images in different aspects to ensure its significance.

Tuning magnetic interaction between two identical perpendicularly magnetized layers by a nonmagnetic spacer layer

Tuning magnetic properties of perpendicularly magnetized system is technologically important and have application in modern spintronics devices. In this article, we have considered TbFe based perpendicular trilayer magnetic system by inserting a nonmagnetic spacer layer in between. A systematic variation in thickness of non-magnetic Ti spacer (S) in the trilayer structure, TbFe (40 nm)/ Ti (0, 2, 5, 10, 15, 30 nm)/ TbFe (40 nm) is explored to understand and correlate the structural, magnetic, and microscopic properties of the system. Magnetostatic coupling dominates in these systems, and the strength of the coupling decreases as the S thickness increases. Ti and Fe forms a interfacial TiFe layer, roughness of which increases as the thickness of S increases. The increase in interfacial roughness causes effective magnetization compensation at S = 30 nm, where Hc and Mr are least compared to other spacer thicknesses. However, for S = 2 nm coupling strength was found to be highest compared to other cases, as a result, magnetic domains are compressed. Further increase in thickness of S leads to isolated domains and finally a single domain state is apparent for higher value of S. The experimental findings are supported with in-depth micromagnetic modeling. Kerr microscopy and first-order reversal imaging reveal nucleation and domain wall propagation as the dominated magnetization reversal process in these systems. These microscopic insights and tunability of magnetic properties of the trilayer system may find use in various spintronics applications.

GAN-Based Encoding Model for Reversible Image Steganography

In carrying out reversible image steganography, the Generative Adversarial Networks (GANs-based) models have proven to be the most suitable deep learning models for image steganography. Image steganography is a steganography system that hides secret data in an image cover medium without arousing suspicion, and it is defined by the ability to reconstruct the cover medium with no visible distortion after the steganography system has been decoded by extracting the hidden data. In this study, we try achieve the encoding phase in image steganography, where two GAN-base models (CycleGAN and DCGAN) were proposed. Empirical analysis was done to determine a better model for the encoding of image steganography. The Peak Signal-to-Noise Ratio (PSNR), the Structural Similarity Index Metric (SSIM), and bit per pixel (bpp) were used as the metrics for the analysis. The outcome of DCGAN yielded (SSIM=0.48; PSNR=19.86; bpp=24.79) and the outcome of using CycleGAN yielded (SSIM=0.97; PSNR=41.45; bpp=24.97). These values concluded that the CycleGAN was preferable over the DCGAN. Hence, the CycleGAN was adopted as the encoding model.

DACO: Distortion/artefact correction for diffusion MRI data

In this paper, we propose a registration-based algorithm to correct various distortions or artefacts (DACO) commonly observed in diffusion-weighted (DW) magnetic resonance images (MRI). The registration in DACO is accomplished by means of a pseudo b0 image, which is synthesized from the anatomical images such as T1-weighted image or T2-weighted image, and a pseudo diffusion MRI (dMRI) data, which is derived from the Gaussian model of diffusion tensor imaging (DTI) or the Hermite model of mean apparent propagator (MAP)-MRI. DACO corrects (1) the susceptibility-induced distortions and (2) the misalignment between the dMRI data and anatomical images by registering the real b0 image to the pseudo b0 image, and corrects (3) the eddy current-induced distortions and (4) the head motions by registering each image in the real dMRI data to the corresponding image in the pseudo dMRI data. DACO estimates the models of artefacts simultaneously in an iterative and interleaved manner. The mathematical formulation of the models and the estimation procedures are detailed in this paper. Using the human connectome project (HCP) data the evaluation shows that DACO could estimate the model parameters accurately. Furthermore, the evaluation conducted on the real human data acquired from clinical MRI scanners reveals that the method could reduce the artefacts effectively. The DACO method leverages the anatomical image, which is routinely acquired in clinical practice, to correct the artefacts, omitting the additional acquisitions needed to conduct the algorithm. Therefore, our method should be beneficial to most dMRI data, particularly to those acquired without field maps or reverse phase-encoding images.

A Ratiometric Photoacoustic Probe with a Reversible Response to Hydrogen Sulfide and Hydroxyl Radicals for Dynamic Imaging of Liver Inflammation.

Reversible imaging probes that allow for the dynamic visualization of the redox cycle between hydroxyl radical (⋅OH) and hydrogen sulfide (H2 S) are vital to probe the redox imbalance-involved pathological process in vivo. Herein, we report a reversible ratiometric photoacoustic (PA) imaging nanoprobe (1-PAIN) for the real-time imaging of ⋅OH/H2 S redox cycle in vivo. 1-PAIN displays a low PA ratio between 690 and 825 nm (PA690 /PA825 ), which significantly increases by ≈5-fold upon oxidation by ⋅OH, and is switched back to the initially low PA690 /PA825 value upon reduction by H2 S. 1-PAIN could dynamically report on the hepatic ⋅OH production in mice during the lipopolysaccharide (LPS)-induced liver inflammation process, and visualize hepatic H2 S generation during the N-acetyl cysteine (NAC)-induced anti-inflammation process. 1-PAIN can act as a useful tool to probe the redox state in living biology, beneficial for the study of redox imbalance-related diseases.