Tone Map Research Articles

Skin Tone Analysis Through Skin Tone Map Generation With Optical Approach and Deep Learning.

Skin tone assessment is critical in both cosmetic and medical fields, yet traditional methods like the individual typology angle (ITA) have limitations, such as sensitivity to illuminants and insensitivity to skinredness. This study introduces an automated image-based method for skin tone mapping by applying optical approaches and deep learning. The method generates skin tone maps by leveraging the illuminant spectrum, segments the skin region from face images, and identifies the corresponding skin tone on the map. The method was evaluated by generating skin tone maps under three standard illuminants (D45, D65, and D85) and comparing the results with those obtained using ITA on skin tone simulationimages. The results showed that skin tone maps generated under the same lighting conditions as the image acquisition (D65) provided the highest accuracy, with a color difference of around 6, which is more than twice as small as those observed under other illuminants. The mapping positions also demonstrated a clear correlation with pigment levels. Compared to ITA, the proposed approach was particularly effective in distinguishing skin tones related toredness. Despite the need to measure the illuminant spectrum and for further physiological validation, the proposed approach shows potential for enhancing skin tone assessment. Its ability to mitigate the effects of illuminants and distinguish between the two dominant pigments offers promising applications in both cosmetic and medicaldiagnostics.

TM-Net: A Neural Net Architecture for Tone Mapping.

Tone mapping functions are applied to images to compress the dynamic range of an image, to make image details more conspicuous, and most importantly, to produce a pleasing reproduction. Contrast Limited Histogram Equalization (CLHE) is one of the simplest and most widely deployed tone mapping algorithms. CLHE works by iteratively refining an input histogram (to meet certain conditions) until convergence, then the cumulative histogram of the result is used to define the tone map that is used to enhance the image. This paper makes three contributions. First, we show that CLHE can be exactly formulated as a deep tone mapping neural network (which we call the TM-Net). The TM-Net has as many layers as there are refinements in CLHE (i.e., 60+ layers since CLHE can take up to 60 refinements to converge). Second, we show that we can train a fixed 2-layer TM-Net to compute CLHE, thereby making CLHE up to 30× faster to compute. Thirdly, we take a more complex tone-mapper (that uses quadratic programming) and show that it too can also be implemented - without loss of visual accuracy-using a bespoke trained 2-layer TM-Net. Experiments on a large corpus of 40,000+ images validate our methods.

Tone mapping high dynamic range images based on region-adaptive self-supervised deep learning

This paper presents a region-adaptive self-supervised deep learning (RASSDL) technique for high dynamic range (HDR) image tone mapping. The RASSDL tone mapping operator (TMO) is a convolutional neural network (CNN) trained on local image regions that can seamlessly tone map images of arbitrary sizes. The training of RASSDL TMO is through the design of a self-supervising target that automatically adapts to the local image regions based on their information contents. The self-supervising target is designed to ensure the tone-mapped output achieves a balance between preserving the relative contrast of the original scene and the visibilities of the fine details to achieve faithful reproduction of the HDR scene. Distinguishing from many existing TMOs that require manual tuning of parameters, RASSDL is parameter-free and completely automatic. Experimental results demonstrate that RASSDL TMO can achieve state-of-the-art performance in terms of preserving overall contrasts, revealing fine details, and being free from visual artifacts.

Adversarial and adaptive tone mapping operator: multi-scheme generation and multi-metric evaluation

Tone mapping is one of the main techniques to convert high-dynamic range (HDR) images into low-dynamic range (LDR) images. We propose to use a variant of generative adversarial networks to adaptively tone map images. We designed a conditional adversarial generative network composed of a U-Net generator and patchGAN discriminator to adaptively convert HDR images into LDR images. We extended previous work to include additional metrics such as tone-mapped image quality index (TMQI), structural similarity index measure, Fréchet inception distance, and perceptual path length. In addition, we applied face detection on the Kalantari dataset and showed that our proposed adversarial tone mapping operator generates the best LDR image for the detection of faces. One of our training schemes, trained via 256 × 256 resolution HDR–LDR image pairs, results in a model that can generate high TMQI low-resolution 256 × 256 and high-resolution 1024 × 2048 LDR images. Given 1024 × 2048 resolution HDR images, the TMQI of the generated LDR images reaches a value of 0.90, which outperforms all other contemporary tone mapping operators.

TONE COMPRESSION ALGORITHM FOR HIGH DYNAMIC RANGE MEDICAL IMAGES

Abstract. We propose here an HDR compression method for medical images based on a windowing operator, an adaptive tone mapping operator, and the probabilistic normal-gamma model. First, we use the windowing operator based on a structural fidelity measure for optimal visualization of the input HDR medical image. Then, we transform the windowed image to the logarithm domain and split it into base and detail layers with the help of the probabilistic normal-gamma model. Base and detail layers are used to make the tone map with help the adaptive tone mapping operator. Finally, the tone mapping result is the LDR image. The proposed method has comparable quality and low computation time compared to other tone mapping operators.

Learning-Based Tone Mapping Operator for Efficient Image Matching

In this paper, we propose a new framework to optimally tone map the high dynamic range (HDR) content for image matching under drastic illumination variations. Since tone mapping operators (TMO) have traditionally been used for displaying HDR scenes, their design is suboptimal when used for computer vision tasks, such as image matching. We address this suboptimality by proposing a two-step framework, consisting of: first, a luminance-invariant guidance model based on a support vector regressor (SVR) to optimally adapt the tone mapping function for image matching; and second, an energy maximization model to generate appropriate training samples for learning the SVR. At each step, we collectively address both stages of keypoint detection and descriptor extraction in the feature matching framework. By locally altering the intrinsic characteristics of the tone mapping function, the learned guidance model facilitates the extraction of local invariant features in the presence of illumination variations. We demonstrate that the proposed TMO significantly outperforms perceptually driven state-of-the-art TMOs on a dataset of HDR scenes characterized by challenging lighting variations, such as day/night transitions.

Continuous Line Drawings and Designs

Continuous Line Drawing (CLD) is a drawing style where a picture consists of a single closed non-intersecting line. This paper presents an automatic algorithm for constructing CLDs, with tone and structural information obtained from input images. The connectivity of the line is maintained through a tree generated by path finding with consideration of the key features for a given image. A branching tree structure is grown incrementally by selecting pixels by a cost function, relating to both the tone map and an importance map. After labeling each branch, an artificial wall is then constructed through a two-stage labeling propagation process to produce a single boundary, interpreted as the final CLD. The presented CLD method is effective and automatic, and provides some opportunities for variations. The paper also shows how to design CLDs from scratch using three steps: building base structures, forming shapes by thickening, and extracting CLDs by tracing the boundary of the shapes.

AN IMPROVED HDR IMAGE PROCESSING USING FAST GLOBAL TONE MAPPING

People always try to reconstruct images that look like original scene. But it is not succeeded up to the expected level because the display devices cannot accommodate the actual r ange of illumination. The original scene is having high dynamic range (HDR) and the display devices are having low dynami c range (LDR) of values. Tone mapping can be used t o display HDR image in an LDR device. In this paper we are trying to de velop a better tone mapping method. A number of i mages with different exposure are fused to form an HDR image.. Here we u sed average method for this which is the simplest o ne. Then by using tone mapping the HDR image is converted into LDR. We tri ed Tone Reproduction Curve (TRC) based global tone mapping. TRC method results faster operation The global tone map ping operator algorithm is simple and does not int roduce ghosting. The image will also free from blur and halo like artifa cts. We took log average of the images to keep the pixel values within limit.

Zonal brightness coherency for video tone mapping

Tone Mapping Operators (TMOs) compress High Dynamic Range (HDR) contents to address Low Dynamic Range (LDR) displays. While many solutions have been designed over the last decade, only few of them can cope with video sequences. Indeed, these TMOs tone map each frame of a video sequence separately, which results in temporal incoherency. Two main types of temporal incoherency are usually considered: flickering artifacts and temporal brightness incoherency. While the reduction of flickering artifacts has been well studied, less work has been performed on brightness incoherency. In this paper, we propose a method that aims at preserving spatio-temporal brightness coherency when tone mapping video sequences. Our technique computes HDR video zones which are constant throughout a sequence, based on the luminance of each pixel. Our method aims at preserving the brightness coherency between the brightest zone of the video and each other zone. This technique adapts to any TMO and results show that it preserves well spatio-temporal brightness coherency. We validate our method using a subjective evaluation. In addition, unlike local TMOs, our method, when applied to still images, is capable of ensuring spatial brightness coherency. Finally, it also preserves video fade effects commonly used in post-production.

색채활용교육의 역량강화를 위한 단계별 표준색표집의 제작 연구

This research designed usable standard color chart which was planned by hue and tone color system. This research studied 5 types standard color chart by designed tone map and preceding research. "Basic Color Chart 14 Colors" was planned for kindergarteners. "Primary Color Chart 63 Colors" was planned for schoolboys. "Middle Grade Color Chart 114 Colors" was planned for junior high school students. "High Grade Color Chart 152 Colors" was planned for senior high school students. "Hue and Tone 205 Colors" was planned for university students and general publics. These 5 types standard color chart were produced the trial color coordinate card and attached the Munsell notation which could reappear the spare color paper when needed. These 5 types standard color chart would be offered the data base for efficient color coordinate education as school age.

Influence of Texture on Perception of Gray Tone Map Symbols

Various equal value gray scales have been employed by cartographers for choosing gray tone area symbols, but often without considering the possible effect of texture. This research questions whethe...

Tonality perception and comprehension: Pitch‐interval interactions

Two experiments investigated the influence of pitch and melodic interval on tonal comprehension and melodic expectation. The stimulus examples for both experiments were composed of a tonal context example followed by a two‐tone melodic fragment. The two‐way factorial design had 12 levels of ending pitch and 25 levels of melodic interval (all intervals within one octave of ending pitch). Subjects in experiment 1 rated how well the melodic fragment fit into the context example tonality. Ratings were three‐dimensional: (1) pitch‐interval interactions corresponding to a diatonic hierarchy, (2) perception of the dominant and tonic, and (3) perception of the three major diatonic triads. Subjects in experiment 2 sang their expected continuations to the melodic fragment. The continuations were influenced by factors similar to those of experiment 1. Continuation profiles could be reconstructed by multiplying corresponding entries from pitch and interval marginal mean profiles, implying that pitch and interval continuation production systems are functionally independent and produce a single response profile by means of a cross‐correlational decision mechanism. Ratings and continuations can be explained by a harmonic mapping model, where the harmonics of a response tone map onto those of the tonic and the first tone of the fragment.

Perceptions of Variable Similarity on Bivariate Choroplethic Maps

The major function of a two-variable map is to depict the spatial variation in the relationship between the two variables mapped. This research studies the methods by which map readers interpret this relationship within each choropleth zone. Using two different map designs, the United States Bureau of the Census colour-coded map, and the continuous tone map, subjects were to form regions of contiguous zones based on perceived relationships between the variables. Both map reading groups performed the task satisfactorily; their methods of solution were similar, and the regions selected were very similar. Each map design produced reasonable results, and each showed some limitations.

Application of Aerial Photographs and Surficial Geologic Maps to the Determination of Suitability of Land for Septic Tank Systems

Research Article| January 01, 1980 Application of Aerial Photographs and Surficial Geologic Maps to the Determination of Suitability of Land for Septic Tank Systems STEPHEN D. CONNORS STEPHEN D. CONNORS Stephen D. Connors is a geologist with the Federal Energy Regulatory Commission, Washington, D.C. Search for other works by this author on: GSW Google Scholar Author and Article Information STEPHEN D. CONNORS Stephen D. Connors is a geologist with the Federal Energy Regulatory Commission, Washington, D.C. Publisher: Association of Environmental & Engineering Geologists First Online: 02 Mar 2017 Online Issn: 1558-9161 Print Issn: 1078-7275 © 1980 Association of Engineering Geologists Environmental & Engineering Geoscience (1980) xvii (3): 153–162. https://doi.org/10.2113/gseegeosci.xvii.3.153 Article history First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation STEPHEN D. CONNORS; Application of Aerial Photographs and Surficial Geologic Maps to the Determination of Suitability of Land for Septic Tank Systems. Environmental & Engineering Geoscience 1980;; xvii (3): 153–162. doi: https://doi.org/10.2113/gseegeosci.xvii.3.153 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyEnvironmental & Engineering Geoscience Search Advanced Search Abstract The majority of homesites in the town of Arcade, Wyoming County, New York rely on individual septic tank systems. Proper construction and regulation of septic tank systems minimize disease transmission and ground water contamination. Appraisal of soil and site conditions is the most important step in determining suitability of land for septic tank systems.Aerial photographs, surficial geology, grain size analysis and permeability tests were utilized to determine the suitability of the area for septic tank systems. Criteria were established using aerial photographs and surficial geologic maps in glaciated areas to determine septic tank suitability without the use of an extensive laboratory program.Results indicate that the town of Arcade has generally unfavorable soil conditions for septic tank systems. Data from this study are presented in the form of a three tone map intended for use by planners. The described method should be applicable to other glaciated areas and land suitability studies. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Air and Bone Conduction Pure Tone Detection Thresholds for Squirrel Monkey

Probe microphone equivalents of monaural pure tone MAP thresholds were determined for seven squirrel monkeys trained to track thresholds by means of a shock avoidance conditioning procedure. Three animals were fitted with audiometric-type bone vibrators cemented permanently to stainless steel screws tapped into the parietal bones, and bone conduction thresholds were obtained. Stimuli were steady and pulsed pure tones from 125 Hz through 16 000 Hz. Head attenuation (cross hearing) and effective contralateral masking levels for broad-band noise were measured. Validity of bone conduction thresholds was checked under conditions of experimentally induced conductive and sensorineural deafness. [Work supported in part by U. S. Veterans Administration and by National Institute of Neurological Diseases and Stoke.] (This paper was originally scheduled for presentation at the Eightieth Meeting, but was not delivered.)