Innovative 3D Depth Map Generation From A Holoscopic 3D Image Based on Graph Cut Technique

Holoscopic 3D imaging is a promising technique for capturing full-colour spatial 3D images using a single aperture holoscopic 3D camera. It mimics fly’s eye technique with a microlens array, which views the scene at a slightly different angle to its adjacent lens that records three-dimensional information onto a two-dimensional surface. This paper proposes a method of depth map generation from a holoscopic 3D image based on graph cut technique. The principal objective of this study is to estimate the depth information presented in a holoscopic 3D image with high precision. As such, depth map extraction is measured from a single still holoscopic 3D image which consists of multiple viewpoint images. The viewpoints are extracted and utilised for disparity calculation via disparity space image technique and pixels displacement is measured with sub-pixel accuracy to overcome the issue of the narrow baseline between the viewpoint images for stereo matching. In addition, cost aggregation is used to correlate the matching costs within a particular neighbouring region using sum of absolute difference (SAD) combined with gradient-based metric and “winner takes all” algorithm is employed to select the minimum elements in the array as optimal disparity value. Finally, the optimal depth map is obtained using graph cut technique. The proposed method extends the utilisation of holoscopic 3D imaging system and enables the expansion of the technology for various applications of autonomous robotics, medical, inspection, AR/VR, security and entertainment where 3D depth sensing and measurement are a concern

Quality assessment of nutrition coverage in the media: A 6 week survey of five popular UK newspapers

Objectives: To investigate the quality of nutrition articles in popular national daily newspapers in the UK and to identify important predictors of article quality. Setting: Newspapers are a primary source of nutrition information for the public. Design: Newspaper articles were collected on 6 days of the week (excluding Sunday) for 6 weeks in summer 2014. Predictors included food type and health outcome, size of article, whether the journalist was named and day of the week. Outcome measures: A validated quality assessment tool was used to assess each article, with a minimum possible score of −12 and a maximum score of 17. Newspapers were checked in duplicate for relevant articles. The association of each predictor on article quality score was analysed adjusting for remaining predictors. A logistic regression model was implemented with quality score as the binary outcome, categorised as poor (score less than zero) or satisfactory (score of zero or more). Results: Over 6 weeks, 141 nutrition articles were included across the five newspapers. The median quality score was 2 (IQR −2–6), and 44 (31%) articles were poor quality. There was no substantial variation in quality of reporting between newspapers once other factors such as anonymous publishing, health outcome, aspect of diet covered and day of the week were taken into account. Particularly low-quality scores were obtained for anonymously published articles with no named journalist, articles that focused on obesity and articles that reported on high fat and processed foods. Conclusions: The general public are regularly exposed to poor quality information in newspapers about what to eat to promote health, particularly articles reporting on obesity. Journalists, researchers, university press officers and scientific journals need to work together more closely to ensure clear, consistent nutrition messages are communicated to the public in an engaging way

Holoscopic Elemental-Image-Based Disparity Estimation Using Multi-Scale, Multi-Window Semi-Global Block Matching

Data Availability Statement: The data presented in this study are available on request from the corresponding author, Bodor Almatrouk, at [email protected]. The data are not publicly available due to commercial privacy.In Holoscopic imaging, a single aperture is used to acquire full-colour spatial images like a fly’s eye by gently altering angles between nearby lenses with a micro-lens array. Due to its simple data collection and visualisation methods, which provide robust and scalable spatial information, and its motion parallax, binocular disparity, and convergence, this technique may be able to overcome traditional 2D imaging issues like depth, scalability, and multi-perspective problems. A novel disparity-map-generating method uses angular information from a single Holoscopic image’s micro-images, or Elemental Images (EIs), to create a scene’s disparity map. Not much research has used EIs instead of Viewpoint Images (VPIs) for disparity estimation. This study investigates whether angular perspective data may replace spatial orthographic data. Using noise reduction and contrast enhancement, EIs with a low resolution and lack of texture are pre-processed to calculate the disparity. The Semi-Global Block Matching (SGBM) technique is used to calculate the disparity between EI pixels. A multi-resolution approach overcomes EIs’ resolution constraints, and a content-aware analysis dynamically modifies the SGBM window size settings to generate disparities across different texture and complexity levels. A background mask and nearby EIs with accurate backgrounds detect and rectify EIs with erroneous backgrounds. Our method generates disparity maps that outperform two state-of-the-art deep learning algorithms and VPIs in real images.This research received no external funding

Assessment of the Heat Capacity by Thermodynamic Approach Based on Density Functional Theory Calculations

The theoretical aspects of the thermodynamic calculation of the Gibbs energy and heat capacity of a crystalline system within the frame of the Density Functional Theory (DFT) are introduced in the present chapter. Various approximations of phonon motion (harmonic, quasiharmonic, and anharmonic) and their effects on the thermodynamic properties are discussed. The theoretical basis of the thermodynamic approach of the heat capacity of crystals for given thermodynamic conditions is presented, having as example six polymorphs of the magnesium hydrides

A New Raw Holoscopic Image Simulator and Data Generation

This article has been accepted for publication in a future proceedings of this conference, but has not been fully edited. Content may change prior to final publication. Citation information: DOI10.1109/ICIVC58118.2023.10270247, 2023 8th International Conference on Image, Vision and Computing (ICIVC

Disparity estimation and enhancement from holoscopic elemental images

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London3D technology has acquired an enormous interest in the last few decades compared to standard 2D imaging. It has the advantage of projecting depth and motion parallax, pro viding a more realistic and natural image. Holoscopic imaging is a promising technique that captures full-colour spatial images using a single-aperture system. A micro-lens array shows the scene fromslightly varying angles between neighbouring lenses, mimicking the f ly’s eye approach and capturing four-dimensional information on a two-dimensional sur face. This technique has the potential to overcome key limitations of traditional 2D imag ing issues like depth, scalability, and multi-perspective problems due to its simple data collection and visualisation method, which provides robust and scalable spatial informa tion, and the additional features of motion parallax, binocular disparity, and convergence. Unlike stereoscopic technology, a holoscopic system is underexplored. Researchers con front a lack of holoscopic cameras to choose from: Lytro (no longer available) and Raytrix (industrial application, more expensive). The need for a low-cost holoscopic image simu lator and dataset to experiment with configurations, build prototypes, and use ground-truth data for exploration, benchmarking, and evaluation is evident. This research introduces a 4D Plenoptic function-based synthetic holoscopic image simulator. The simulator was developed to produce raw holoscopic images faster and simpler than prior versions. A comprehensive dataset with several micro-lens array configurations was developed and provided via the simulator. This dataset can be used to assess the resolution trade-off be tween angular and spatial data to help researchers choose micro-lens array configurations. Aninnovative disparity map generation technique is proposed, which produces a disparity mapof ascene from a single holoscopic image based on angular information preserved in its micro-images, also known as elemental images (EIs) The use of EIs for disparity es timation instead of traditional viewpoint images (VPIs) has not been extensively studied. This research aims to explore the feasibility of utilising angular perspective information instead of spatial orthographic information. Computing the disparity starts with enhanc ing the quality of EIs, which often suffer from low resolution and lack of texture, a pre processing phase is carried out using noise reduction and contrast enhancement. The dis parity between EIs pixels is calculated using the Semi-Global Block Matching (SGBM) technique, which is improved by employing a multi-resolution approach to overcome the resolution constraints of EIs as well as performing a content-aware analysis to dynami cally modify the SGBMwindowsize settings generating disparities across different levels of texture and complexity within the EIs. Finally, a weighted least squares (WLS) filter is used to improve the optimisation process. In addition, EIs with inaccurate backgrounds are detected and corrected with the use of a background mask and neighbouring EIs that contain accurate background information. The evaluation has revealed that the suggested technique has successfully generated disparity maps that surpass the accuracy of VPIs in real images and outperform two state-of-the-art deep learning algorithms. The method was also evaluated across many EI resolutions to test out the ideal resolution. Current disparity estimation approaches based on EIs suffer from significant performance decreases, particularly in texture-less regions. A novel method is proposed for performing EIs labelling and grouping directly from a holoscopic image by selecting the appropriate EIs that include the same object to use this information to reduce the disparity error in the texture-less regions. To begin, a subset of VPIs are extracted from the holoscopic image and subjected to conventional image segmentation. Next, labels are applied to the EIs that correspond to each object segmented from the VPIs using VPIs/EIs pixel mapping. To further improve the segmentation, we employ content-based image retrieval (CBIR), in which the query images are automatically chosen from the previously established seg mentation. The texture-less elemental images of the disparity map computed from the holoscopic image are updated using the labelling data. Positive findings from the evalua tion indicate that the proposed technique has helped reduce the disparity map error. The evaluation result outperformed state-of-the-art depth generation techniques, and the proposed technique enlarges the industrial application of 3D imaging applications such as AR/VR, inspection, robotics, security and entertainment

Chemical Exposure-Induced Changes in the Expression of Neurotrophins and Their Receptors in the Main Olfactory System of Mice Lacking TRPM5-Expressing Microvillous Cells

Functional maintenance of the mammalian main olfactory epithelium (MOE) is challenging because of its direct exposure to a wide spectrum of environmental chemicals. We previously reported that transient receptor potential channel M5-expressing microvillous cells (TRPM5-MCs) in the MOE play an important role in olfactory maintenance. To investigate the underpinning mechanisms, we exposed transcription factor Skn-1a knockout (Skn-1a−/−) mice lacking TRPM5-MCs, and TRPM5-GFP mice to either vehicle (water) or a mixture of odorous chemicals and chitin for two weeks and analyzed the expression of olfactory signaling proteins using immunolabeling and neurotrophin (NT) and NT receptor (NTR) gene transcripts using real-time quantitative PCR. The chemical exposure did not significantly attenuate the immunolabeling of olfactory signaling proteins. Vehicle-exposed Skn-1a−/− and TRPM5-GFP mice expressed similar levels of NT and NTR gene transcripts in the MOE and olfactory bulb. Chemical exposure significantly increased MOE expression of p75NTR in Skn-1a−/− mice, while p75NTR expression was reduced in TRPM5-GFP mice, as compared to vehicle-exposed mice. Additionally, our RNA in situ hybridization analysis and immunolabeling confirmed MOE expression of most NTs and NTRs. Together, these results indicate that TRPM5-MCs and chemical exposure influence expression of some NTs and NTRs in the MOE and olfactory bulb (OB)