Vegetation Greening for Winter Oblique Photography Using Cycle-Consistence Adversarial Networks

A 3D city model is critical for the construction of a digital city. One of the methods of building a 3D city model is tilt photogrammetry. In this method, oblique photography is crucial for generating the model because the visual quality of photography directly impacts the model’s visual effect. Yet, sometimes, oblique photography does not have good visual quality due to a bad season or defective photographic equipment. For example, for oblique photography taken in winter, vegetation is brown. If this photography is employed to generate the 3D model, the result would be bad visually. Yet, common methods for vegetation greening in oblique photography rely on the assistance of the infrared band, which is not available sometimes. Thus, a method for vegetation greening in winter oblique photography without the infrared band is required, which is proposed in this paper. The method was inspired by the work on CycleGAN (Cycle-consistence Adversarial Networks). In brief, the problem of turning vegetation green in winter oblique photography is considered as a style transfer problem. Summer oblique photography generally has green vegetation. By applying CycleGAN, winter oblique photography can be transferred to summer oblique photography, and the vegetation can turn green. Yet, due to the existence of “checkerboard artifacts”, the original result cannot be applied for real production. To reduce artifacts, the generator of CycleGAN is modified. As the final results suggest, the proposed method unlocks the bottleneck of vegetation greening when the infrared band is not available and artifacts are reduced.

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Validation Methods of Geometric 3D-CityGML Data for Urban Wind Simulations

E3S Web of Conferences ◽

10.1051/e3sconf/201912810006 ◽

2019 ◽

Vol 128 ◽

pp. 10006 ◽

Cited By ~ 2

Author(s):

Younis Saida Saeedrashed ◽

Ali Cemal Benim

Keyword(s):

Healing Process ◽

Flow Simulation ◽

Software Tools ◽

Geometrical Structures ◽

Geometric Data ◽

3D City Model ◽

City Model ◽

Closed Shells

Validation of the geometric data such as 3D city model is quite crucial for simulation tasks, since the simulation process strongly correlates to the quality of geometric data being meshed. Validation methodology and healing of the 3D city models using different tools are presented. The most common inherited geometrical errors are checked and analyzed. Accordingly, an appropriate healing process to the case study is performed, which illustrates that the required closed solids and closed shells are obtained within the geometrical structures of the 3D city model being processed. Also, in this paper we compare some related open source and commercial software tools for the validation and healing process. It is noticed that they differ from each other in performing the required healing process. Some of them are quite good in healing specific errors, whereas not successful in healing the rest of errors. The goal of the paper is to obtain more understanding of the geometric validation and healing capabilities of various software tools, and the qualities of generated meshes, to lead to more effective and reliable simulations in the field of urban wind flow simulation.

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CityEngine: An Introduction to Rule-Based Modeling

Urban Informatics - The Urban Book Series ◽

10.1007/978-981-15-8983-6_35 ◽

2021 ◽

pp. 637-662

Author(s):

Tom Kelly

Keyword(s):

Software Package ◽

Rule Based ◽

3D City Model ◽

Urban Models ◽

Gis Data ◽

Modeling Software ◽

City Model ◽

2D Data ◽

Rule Based Approach

AbstractCityEngine is a rule-based urban modeling software package. It offers a flexible pipeline to transform 2D data into 3D urban models. Typical applications include processing 2D urban cartographic geographic information system (GIS) data to create a detailed 3D city model, creating a detailed visualization of a proposed development, or exploring the design space of a potential project. The rule-based core of Esri’s CityEngine has some unique advantages: Huge cities can be created as easily as small ones, while the quality of the models is consistent throughout. Additionally, this rule-based approach means that large design spaces can be explored quickly, interactively, and analytically compared. Such advantages must be carefully balanced against the increased time to create and parameterize the rules and the sometimes stylistic or approximate models created; coming from more traditional workflows, CityEngine’s pipeline can be initially overwhelming. We introduce the principal workflows and the flexibility they afford, sketch the procedural programming language used, and discuss the export pathways available.

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Enhancing Visual Quality of Multi-view 360 Video Compression Pipeline

Proceedings of the International Display Workshops ◽

10.36463/idw.2019.0135 ◽

2019 ◽

pp. 135

Author(s):

Junyoung Yun ◽

Hong-Chang Shin ◽

Gwangsoon Lee ◽

Jong-Il Park

Keyword(s):

Video Compression ◽

Visual Quality

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ART-UP: A Novel Method for Generating Scanning-Robust Aesthetic QR Codes

ACM Transactions on Multimedia Computing Communications and Applications ◽

10.1145/3418214 ◽

2021 ◽

Vol 17 (1) ◽

pp. 1-23

Author(s):

Mingliang Xu ◽

Qingfeng Li ◽

Jianwei Niu ◽

Hao Su ◽

Xiting Liu ◽

...

Keyword(s):

State Of The Art ◽

Visual Quality ◽

Qr Code ◽

Quick Response ◽

Estimation Model ◽

Qr Codes ◽

Excellent Performance ◽

Novel Method ◽

Coarse To Fine

Quick response (QR) codes are usually scanned in different environments, so they must be robust to variations in illumination, scale, coverage, and camera angles. Aesthetic QR codes improve the visual quality, but subtle changes in their appearance may cause scanning failure. In this article, a new method to generate scanning-robust aesthetic QR codes is proposed, which is based on a module-based scanning probability estimation model that can effectively balance the tradeoff between visual quality and scanning robustness. Our method locally adjusts the luminance of each module by estimating the probability of successful sampling. The approach adopts the hierarchical, coarse-to-fine strategy to enhance the visual quality of aesthetic QR codes, which sequentially generate the following three codes: a binary aesthetic QR code, a grayscale aesthetic QR code, and the final color aesthetic QR code. Our approach also can be used to create QR codes with different visual styles by adjusting some initialization parameters. User surveys and decoding experiments were adopted for evaluating our method compared with state-of-the-art algorithms, which indicates that the proposed approach has excellent performance in terms of both visual quality and scanning robustness.

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Effect of defocus combined with rotation on the optical performance of trifocal toric IOLs

European Journal of Ophthalmology ◽

10.1177/11206721211002121 ◽

2021 ◽

pp. 112067212110021

Author(s):

Javier Ruiz-Alcocer ◽

Irene Martínez-Alberquilla ◽

Amalia Lorente-Velázquez ◽

José F Alfonso ◽

David Madrid-Costa

Keyword(s):

Visual Quality ◽

Optical Quality ◽

Refractive Errors ◽

Focal Points ◽

Modulation Transfer ◽

Optical Analysis ◽

Toric Intraocular Lens ◽

Toric Iols ◽

Reference Situation

Purpose: To objectively analyze the optical quality of the FineVision Toric intraocular lens (IOL) with two cylinder powers when different combinations of rotations and residual refractive errors are induced. Methods: This study assessed the FineVision Toric IOL with two different cylinder powers: 1.5 and 3.0 diopters (D). Three different rotation positions were considered: centered, 5° and 10° rotated. An optical bench (PMTF) was used for optical analysis. The optical quality of the IOLs was calculated by the modulation transfer function (MTF) at five different focal points (0.0, 0.25, 0.50, 0.75, and 1.00 D). Results: The MTF averaged value of the reference situation was 38.58 and 37.74 for 1.5 and 3.0 D of cylinder, respectively. For the 1.5 D cylinder, the combination of 5° of rotation with a defocus of 0.25, 0.50, 0.75, and 1.0 D induced a decrease on the MTF of 12.39, 19.94, 23.43, 24.23 units, respectively. When induced rotation was 10°, the MTF decrease was 17.26, 23.40, 24.33, 24.48 units, respectively. For the 3.0 D cylinder, the combination of 5° with 0.25, 0.50, 0.75, and 1.0 D of defocus, induced a decrease on the MTF of 12.51, 18.97, 22.36, 22.48 units, respectively. When induced rotation was 10°, the MTF decrease was: 18.42, 21.57, 23.08, and 23.61 units, respectively. Conclusion: For both FineVision Toric IOLs there is a certain optical tolerance to rotations up to 5° or residual refractive errors up to 0.25 D. Situations over these limits and their combination would affect the visual quality of patients implanted with these trifocal toric IOLs.

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The Visual Quality of Teleoperated Driving Scenarios How good is good enough?

2020 International Symposium on Networks, Computers and Communications (ISNCC) ◽

10.1109/isncc49221.2020.9297343 ◽

2020 ◽

Author(s):

Stefan Neumeier ◽

Simon Stapf ◽

Christian Facchi

Keyword(s):

Visual Quality

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A New Instrument for Evaluating the Visual Quality of Air

Journal of the Air Pollution Control Association ◽

10.1080/00022470.1967.10469006 ◽

1967 ◽

Vol 17 (7) ◽

pp. 467-469 ◽

Cited By ~ 54

Author(s):

Norman C. Ahlquist ◽

Robert J. Charlson

Keyword(s):

Visual Quality ◽

New Instrument

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K out of N Secret Sharing Scheme for Multiple Color Images with Steganography and Authentication

International Journal of Image and Graphics ◽

10.1142/s0219467816500108 ◽

2016 ◽

Vol 16 (02) ◽

pp. 1650010 ◽

Cited By ~ 1

Author(s):

P. Mohamed Fathimal ◽

P. Arockia Jansi Rani

Keyword(s):

Secret Sharing ◽

Visual Quality ◽

Color Images ◽

Pixel Expansion ◽

Image Sharing ◽

Digital Ecosystem ◽

Sharing Scheme ◽

Text Steganography ◽

Key Aspects

With our lives trundling toward a fully-digital ecosystem in break-neck speed, today’s encryption and cryptography are facing the challenge of ensuring security and future-readiness of our transactions. When such transactions involve multiple hands, transmission of such data in discrete and recoverable parts (secret shares) guarantees confidentiality. This paper’s objective is to present a foolproof way of multiple secret sharing, eliminating issues such as half-toning and degradation of visual quality of the recovered images. This [Formula: see text] out of [Formula: see text] steganography and authenticated image sharing (SAIS) scheme for multiple color images generates [Formula: see text] relevant shares with the ability to reconstruct the secret images using [Formula: see text] shares and facility to find out any move for appropriation of share cover images. The key aspects of this proposed scheme is to use simple Boolean and arithmetic operations with reduction of computational complexity from [Formula: see text] to [Formula: see text] and to share multiple images without any pixel expansion.

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Aspheric Intraocular Lenses Implantation for Cataract Patients with Extreme Myopia

ISRN Ophthalmology ◽

10.1155/2014/403432 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Yanwen Fang ◽

Yi Lu ◽

Aizhu Miao ◽

Yi Luo

Keyword(s):

Contrast Sensitivity ◽

Visual Quality ◽

Intraocular Lenses ◽

Wavefront Aberrations ◽

Spatial Frequencies ◽

Aspheric Iol ◽

Significant Difference ◽

Composite Scores ◽

Cataract Patients

Objective. To evaluate the postoperative visual quality of cataract patients with extreme myopia after implantation of aspheric intraocular lenses (IOLs). Methods. Thirty-three eyes were enrolled in this prospectivestudy. Eighteen eyes with an axial length longer than 28 mm were included in the extreme myopia group, and the other 15 eyes were included in the nonextreme myopia group. Phacoemulsification and aspheric IOL implantation were performed. Six months after cataract surgery, best-corrected visual acuity (BCVA), contrast sensitivity, and wavefront aberrations were measured, and subjective visual quality was assessed. Results. The BCVA improved significantly after surgery for both groups, and patients in the nonextreme myopia group achieved better postoperative BCVA due to better retinal status of the eyes. The evaluation of contrast sensitivity without glare was the same in both groups, whereas patients in the nonextreme myopia group performed better at intermediate spatial frequencies under glare conditions. The two groups did not show a significant difference in high-order aberrations. With regard to subjective visual quality, the composite scores of both groups did not differ significantly. Conclusions. Aspheric IOLs provided good visual outcomes in cataract patients with extreme myopia. These patients should undergo careful evaluation to determine the maculopathy severity level before surgery.

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