Kwan-Hee Yoo
Chungbuk National University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Kwan-Hee Yoo.
Optics Express | 2012
Ki-Chul Kwon; Munkh-Uchral Erdenebat; Ji-Seong Jeong; Jeong-Hun Choi; Nam Kim; Jae-Hyeung Park; Young-Tae Lim; Kwan-Hee Yoo
In an integral imaging display, the computer-generated integral imaging method has been widely used to create the elemental images from a given three-dimensional object data. Long processing time, however, has been problematic especially when the three-dimensional object data set or the number of the elemental lenses are large. In this paper, we propose an image space parallel processing method, which is implemented by using Open Computer Language (OpenCL) for rapid generation of the elemental images sets from large three-dimensional volume data. Using the proposed technique, it is possible to realize a real-time interactive integral imaging display system for 3D volume data constructed from computational tomography (CT) or magnetic resonance imaging (MRI) data.
Journal of The Optical Society of Korea | 2012
Gang Li; Ki-Chul Kwon; Gwan-Ho Shin; Ji-Seong Jeong; Kwan-Hee Yoo; Nam Kim
In this paper, we present a novel integral imaging pickup method. We extract each pixels actual depth data from a real objects surface using a depth camera, then generate elemental images based on the depth map. Since the proposed method generates elemental images without a lens array, it has simplified the pickup process and overcome some disadvantages caused by a conventional optical pickup process using a lens array. As a result, we can display a three-dimensional (3D) image in integral imaging. To show the usefulness of the proposed method, an experiment is presented. Though the pickup process has been simplified in the proposed method, the experimental results reveal that it can also display a full motion parallax image the same as the image reconstructed by the conventional method. In addition, if we improve calculation speed, it will be useful in a real-time integral imaging display system.
Applied Optics | 2013
Do-Hyeong Kim; Munkh-Uchral Erdenebat; Ki-Chul Kwon; Ji-Seong Jeong; Jae-Won Lee; Kyung-Ah Kim; Nam Kim; Kwan-Hee Yoo
This paper proposes an open computer language (OpenCL) parallel processing method to generate the elemental image arrays (EIAs) for hexagonal lens array from a three-dimensional (3D) object such as a volume data. Hexagonal lens array has a higher fill factor compared to the rectangular lens array case; however, each pixel of an elemental image should be determined to belong to the single hexagonal lens. Therefore, generation for the entire EIA requires very large computations. The proposed method reduces processing time for the EIAs for a given hexagonal lens array. By using the proposed image space parallel processing (ISPP) method, it can enhance the processing speed that generates the 3D display of real-time interactive integral imaging for hexagonal lens array. In our experiment, we implemented the EIAs for hexagonal lens array in real-time and obtained a good processing time for a large of volume data for multiple cases of lens arrays.
Biomedical Optics Express | 2015
Ki-Chul Kwon; Ji-Seong Jeong; Munkh-Uchral Erdenebat; Yan-Ling Piao; Kwan-Hee Yoo; Nam Kim
Due to the limitations of micro lens arrays and camera sensors, images on display devices through the integral imaging microscope systems have been suffering for a low-resolution. In this paper, a resolution-enhanced orthographic-view image display method for integral imaging microscopy is proposed and demonstrated. Iterative intermediate-view reconstructions are performed based on bilinear interpolation using neighborhood elemental image information, and a graphics processing unit parallel processing algorithm is applied for fast image processing. The proposed method is verified experimentally and the effective results are presented in this paper.
Optical Engineering | 2014
Ji-Seong Jeong; Ki-Chul Kwon; Munkh-Uchral Erdenebat; Yan-Ling Piao; Nam Kim; Kwan-Hee Yoo
Abstract. A depth camera has been used to capture the depth data and color data for real-world objects. As an integral imaging display system is broadly used, the elemental image array for the captured data needs to be generated and displayed on liquid crystal display. We proposed a real-time integral imaging display system using image processing to simplify the optical arrangement and graphics processing unit parallel processing to reduce the time for computation. The proposed system provides elemental images generated at a rate of more than 30 fps with a resolution of 1204×1204 pixels, where the size of each display panel pixel was 0.1245 mm, and an array of 30×30 lenses, where each lens was 5×5 mm.
Applied Optics | 2014
Ki-Chul Kwon; Ji-Seong Jeong; Munkh-Uchral Erdenebat; Young-Tae Lim; Kwan-Hee Yoo; Nam Kim
A real-time interactive orthographic-view image display of integral imaging (II) microscopy that includes the generation of intermediate-view elemental images (IVEIs) for resolution enhancement is proposed. Unlike the conventional II microscopes, parallel processing through a graphics processing unit is required for real-time display that generates the IVEIs and interactive orthographic-view images in high speed, according to the user interactive input. The real-time directional-view display for the specimen for which 3D information is acquired through II microscopy is successfully demonstrated by using resolution-enhanced elemental image arrays. A user interactive feature is also satisfied in the proposed real-time interactive display for II microscopy.
Journal of The Optical Society of Korea | 2012
Munkh-Uchral Erdenebat; Ganbat Baasantseren; Nam Kim; Ki-Chul Kwon; Jina Byeon; Kwan-Hee Yoo; Jae-Hyeung Park
A three-dimensional integral-floating display with 360 degree horizontal viewing angle is proposed. A lens array integrates two-dimensional elemental images projected by a digital micro-mirror device, reconstructing three-dimensional images. The three-dimensional images are then relayed to a mirror via double floating lenses. The mirror rotates in synchronization with the digital micro-mirror device to direct the relayed three-dimensional images to corresponding horizontal directions. By combining integral imaging and the rotating mirror scheme, the proposed method displays full-parallax three-dimensional images with 360 degree horizontal viewing angle.
Eurasip Journal on Image and Video Processing | 2010
Ki-Chul Kwon; Young-Tae Lim; Nam Kim; Kwan-Hee Yoo; Jong-Myeon Hong; Gi-Chang Park
Biomedical research has been performed by using advanced information techniques, and micro-high-quality stereo images have been used by researchers and/or doctors for various aims in biomedical research and surgery. To visualize the stereo images, many related devices have been developed. However, the devices are difficult to learn for junior doctors and demanding to supervise for experienced surgeons. In this paper, we describe the development of a high-definition (HD) three-dimensional (3D) stereoscopic imaging display system for operating a microscope or experimenting on animals. The system consists of a stereoscopic camera part, image processing device for stereoscopic video recording, and stereoscopic display. In order to reduce eyestrain and viewer fatigue, we use a preexisting stereo microscope structure and polarized-light stereoscopic display method that does not reduce the quality of the stereo images. The developed system can overcome the discomfort of the eye piece and eyestrain caused by use over a long period of time.
Journal of Medical Systems | 2012
Ki-Chul Kwon; Young-Tae Lim; Chul-Ho Kim; Nam Kim; Kwan-Hee Yoo; Seong-Ho Son; Soon-Ik Jeon
In the breast-cancer image detection device field, remarkable advancements have been made in the breast cancer detection method using microwave radiation that satisfies the conditions required by Institute of Medicine (IOM). This paper is for embodying the microwave analysis breast tumor detection system that can analyze the permittivity and the conductivity of the breast inside, discover breast tumors, and easily check the various analytical information of the scatter and size of tumors inside breasts. The microwave breast tumor detection system is composed of an antenna array and the RF transceiver for the acquiring of microwave exposure information; the inverse scattering algorithm for searching the permitivity, conductivity and position of a material, and graphic user interface software that includes the visualization and various analyses of acquired data. The embodied system has shown the same-level function of tumor detection even in the type of heterogeneously dense material that is difficult to detect through mammography by experimentations with four kinds of classifications according to the distribution of lactiferous duct inside the breast.
Journal of The Optical Society of Korea | 2014
Munkh-Uchral Erdenebat; Ki-Chul Kwon; Erkhembaatar Dashdavaa; Yan-Ling Piao; Kwan-Hee Yoo; Ganbat Baasantseren; Young Min Kim; Nam Kim
An enhanced 360-degree integral-floating three-dimensional display system using a hexagonal lens array and a hidden point removal operator is proposed. Only the visible points of the chosen three-dimensional point cloud model are detected by the hidden point removal operator for each rotating step of the anamorphic optics system, and elemental image arrays are generated for the detected visible points from the corresponding viewpoint. Each elemental image of the elemental image array is generated by a hexagonal grid, due to being captured through a hexagonal lens array. The hidden point removal operator eliminates the overlap problem of points in front and behind, and the hexagonal lens array captures the elemental image arrays with more accurate approximation, so in the end the quality of the displayed image is improved. In an experiment, an anamorphic-optics-system-based 360-degree integral-floating display with improved image quality is demonstrated.