Demo Data from EDBT 2026 / reviewers in the wild / expert
Hyun-Gyu Lee
dblp:129/3650
· DBLP profile ↗
7ranked-venue papers
4as first author
0since 2021 · last 2019
0000-0002-6123-2556ORCID · reported
Domains — the database's venue-derived domains; a paper can count in several
Graphics, computer vision, multimedia, augmented reality and games · 5 · 2 first-authorApplied, interdisciplinary, general and emerging computing · 2 · 2 first-author
Expertise — from the expertise taxonomy: the topics of the expert's papers under the CCF categories. A weight counts papers with recency: 1 for a paper about the topic, 0.3 when the topic is its context, halved every five years.
| Computer graphics and multimedia
1 paper |
Multimedia systems and quality of experience · 46% Image and video coding · 30% Image and video processing · 23% |
Topics — the 5 heaviest of 5, each with the papers that count most for it
| Topic | Weight | Papers | Last | Evidence papers |
|---|---|---|---|---|
Multimedia systems and quality of experience
adaptive bitrate streaming |
0.2 | 1 | 2016 | Adaptive Bitrate Selection for Video Encoding with Reduced Block Artifacts · ACM Multimedia 2016 |
Image and video processing › image restoration › compression artifact removal
blocking artifact reduction |
0.2 | 1 | 2016 | Adaptive Bitrate Selection for Video Encoding with Reduced Block Artifacts · ACM Multimedia 2016 |
Image and video coding › video compression › video codec
video encoding |
0.2 | 1 | 2016 | Adaptive Bitrate Selection for Video Encoding with Reduced Block Artifacts · ACM Multimedia 2016 |
Multimedia systems and quality of experience
video quality assessment |
0.2 | 1 | 2016 | Adaptive Bitrate Selection for Video Encoding with Reduced Block Artifacts · ACM Multimedia 2016 |
Image and video coding
perceptual quality optimization |
0.1 | 1 | 2016 | Adaptive Bitrate Selection for Video Encoding with Reduced Block Artifacts · ACM Multimedia 2016 |
Methods — techniques the papers use, named apart from their topics
objective function optimization · 0.2content-based image analysis · 0.2
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2019 | Cell Segmentation for Quantitative Analysis of Anodized TiO$_2$ FoilabstractWe propose a quantitative analysis method using cell segmentation to evaluate the coating quality of anodic oxide. In order to identify each cell in a titania surface, a boundary region is adaptively detected according to the regional intensity distribution, and a boundary distance map is projected onto the scanning electron microscope (SEM) image of the titania surface. Each cell in the projected image is divided via clustering centered on the local maximum point. The uniformities of the cell distribution, size, and thickness are measured using the angle difference, size difference, and brightness difference between adjacent cells to comprehensively evaluate the quantitative alignment of the titania surface. The proposed method demonstrates the best performance in both cell detection and cell segmentation for SEM images of the titania surface compared with the state-of-the-art methods. The quantitative analysis of the anodic oxide film alignment was verified using color coding, histogram, and quantification of uniformity. Hyun-Gyu Lee |
IEEE Trans. Ind. Informatics | 1 |
| 2018 | Nucleus Segmentation Using Gaussian Mixture based Shape ModelsabstractWe identify cells in microscopy images with stained nuclei, using the following process: Candidate seeds for nuclei are identified as extrema in a Laplacian-of-Gaussian space, and weak candidates are eliminated from clusters obtained by ellipse fitting; a region of interest for each nucleus is then defined by combining local and global thresholding; and these regions are repeatedly merged and split by modeling the shape of a nucleus and measuring the roughness of the shared boundaries connected nuclei. This method showed superior abilities to detect the nucleus regions and to split the boundaries of connected nuclei. Our experiments show higher scores in comparison with five other techniques in terms of eight evaluation metrics. Hyun-Gyu Lee |
IEEE J. Biomed. Health Informatics | 1 |
| 2017 | Modeling structural dissimilarity based on shape embodiment for cell segmentationabstractAccurate cell segmentation is one of the critical, yet challenging problems in microscopy images due to ambiguous boundaries as well as a wide variation of shapes and sizes of cells. Even though a number of existing methods have achieved decent results for cell segmentation, boundary vagueness between adjoining cells tended to cause generation of perceptually inaccurate segmentation of stained nuclei. We propose a segmentation method of cells based on structural dissimilarity between embodied and imaged cells. From assumption that the shape of the region of adjoining cells follows a 2D Gaussian mixture model, the cell region is divided by an expectation-maximization method. The lowest structural dissimilarity using embodied cells decides on the number of components of the 2D Gaussian mixture model. The region of interest is extracted by implementation of both global and local thresholdings, which performs binarization of the local image with a seed at the center, where the seed is obtained by the maximally stable extremal regions. Our approach presented considerably higher evaluation scores compared with other five existing methods in terms of both accuracies of region of interest (ROI) detection and boundary discrimination. Hyun-Gyu Lee, Adiba Orzikulova, Bo-Gyu Park |
ICIP | 1 |
| 2016 | Weighted SVM with classification uncertainty for small training samplesabstractExisting maximum-margin support vector machines (SVMs) generate a hyperplane which produces the clearest separation between positive and negative feature vectors. These SVMs are effective when datasets are large. However, when few training samples are available, the hyperplane is easily influenced by outliers that are geometrically located in the opposite class. We propose a modified SVM which weights feature vectors to reflect the local density of support vectors and quantifies classification uncertainty in terms of the local classification capability of each training sample. We derive a primal formulation of an SVM that incorporates those modifications, and implement an RC-margin SVM of the simplest form. We evaluated our model on the recognition of handwritten numerals, and obtained higher recognition rate than a standard maximum-margin SVM, a weighted SVM, or an SVM which accounts for classification uncertainty. Min-Kook Choi, Hyun-Gyu Lee |
ICIP | 2 |
| 2016 | Adaptive Bitrate Selection for Video Encoding with Reduced Block ArtifactsabstractBlocking artifacts, commonly introduced during video encoding, are one of the major causes of reduced perceptual video quality. The trade-off between these artifacts and bitrate can be improved by adaptively selecting frames from a set of video copies encoded at different bitrates, prior to actual video encoding. We propose a new direction of constructing mixed bitrate video based on content-based image analysis on each video frame, which was posed as a problem of pre-analysis for the final video encoding step. The proposed method consists of the following steps: First, we define a simple and fast impact metric in order to identify the blocking artifacts in each frame of multiple videos, encoded at different bitrates. Based on the impact metric, we generate a blocking artifact density functions for the available bitrates, on the whole video. Finally, we define and optimize our objective function from the blocking artifact density functions in order to select a bitrate with minimum perceptual blockiness and file size for each frame. We validated our method throughout multiple types of videos, showing improved visual quality for the same file size based on commonly used quality assessment measures, such as MSU blocking, MSU blurring, SSIM, 3SSIM, and stSSIM. The reduction rates of average file size and average blocking artifact were about 4.9% and 8.3% over maximum bitrate encoding, respectively. Min-Kook Choi, Hyun-Gyu Lee, Minseok Song 0002 |
ACM Multimedia | 2 |
| 2016 | A bag-of-regions representation for video classification
Min-Kook Choi, Ziyu Wang 0005, Hyun-Gyu Lee |
Multim. Tools Appl. | 3 |
| 2013 | Grain-oriented segmentation of scanning electron microscope imagesabstractQuantitative analysis of nanostructures from scanning electron microscope (SEM) images requires a clear segmentation of grains and their boundaries. This is not provided by active contour models, which also require user guidance. Our automatic technique creates a rough representation of grain boundaries by adaptive thresholding. It then performs raycasting from a rectangular grid of seed points to ensure that the grain shapes are convex, and selects the best result for each grain. The whole process can be repeated several times to improve the segmentation. We present results for images of titanium foil, which show that our approach compares favorably in terms of speed and segmentation quality with four competing techniques. Hyun-Gyu Lee, Min-Kook Choi |
ICIP | 1 |