• Journal of Korea Multimedia Society
• /
• v.17 no.7
• /
• pp.818-828
• /
• 2014

After emerging of Microsoft Kinect, the interest in three-dimensional (3D) depth image was significantly increased. Depth image data of an object can be converted to 3D coordinates by simple arithmetic calculation and then can be reconstructed as a 3D model on computer. However, because the surface coordinates can be acquired only from the front area facing Kinect, total solid which has a closed surface cannot be reconstructed. In this paper, 3D registration method for multiple Kinects was suggested, in which surface information from each Kinect was simultaneously collected and registered in real time to build 3D total solid. To unify relative coordinate system used by each Kinect, 3D perspective transform was adopted. Also, to detect control points which are necessary to generate transformation matrix, 3D randomized Hough transform was used. Once transform matrices were generated, real time 3D reconstruction of various objects was possible. To verify the usefulness of suggested method, human arms were 3D reconstructed and the volumes of them were measured by using four Kinects. This volume measuring system was developed to monitor the level of lymphedema of patients after cancer treatment and the measurement difference with medical CT was lower than 5%, expected CT reconstruction error.

• The KIPS Transactions:PartB
• /
• v.16B no.5
• /
• pp.377-384
• /
• 2009

A new algorithm in order to classify various contents in the image documents, such as text, figure, graph, table, etc. is proposed in this paper by classifying contents using texture-based PCA, and by segmenting document images using local entropy-based histogram. Local entropy and histogram made the binarization of image document not only robust to various transformation and noise, but also easy and less time-consuming. And texture-based PCA algorithm for each segmented region was taken notice of each content in the image documents having different texture information. Through this, it was not necessary to establish any pre-defined structural information, and advantages were found from the fact of fast and efficient classification. The result demonstrated that the proposed method had shown better performances of segmentation and classification for various images, and is also found superior to previous methods by its efficiency.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.27 no.1
• /
• pp.73-86
• /
• 1997

This study was performed to assess the analyzing methods developed to detect clinically and quantitatively longitudinal bone changes. Through preliminary experiment, accuracy of Cu-Eq value conversion to the mass of HA was examined. For main experiment, 15 intraoral radiograms taken at soon, 1st, 2nd, 4th, and 6th week after implantation of mixture in extracted sites of 3 cases were used. We took the radiograms with copper step wedge as test object and HA phantom X -ray taking was standardized by using Rinn XCP device customized directly to the individual dentition with resin bite block. The images inputted by Quick scanner into computer were digitized and analyzed by NIH image program. The stability of the copper equivalent transformation and the usefulness of two analyzing methods by ROI and Reslice were examined. Obtained results as follows: 1) On the Cu equivalent images, the coefficient of variation in the measurement of Cu-Eq. value of ROI ranged from 0.05 to 0.24 and showed high reproducibility. 2) All results obtained by resliced contiguous image were coincident with those obtained from the assessment by ROI and formation of plot profile. 3) On the stacked and resliced image at the line of interest, we could analyze directly and quantitatively the longitudinal changes at several portions by plot profile and qualitatively by surface plot. 4) Implant area showed marked resorption till 2 weeks after implantation and showed significant increase in Cu-Eq. value at 6th week(p<0.01) and periapical area showed increase in Cu-Eq. value at 6th week compared to after-operation's.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.15 no.5
• /
• pp.163-168
• /
• 2015

Recent exhibition's paradigm is changing from the existing unidirectional oriented exhibition form to a form of interactive hands-on exhibits that viewers can get and realistically feel a variety of information. Hands-on exhibit embodies the human interface by utilizing light, sound, pressure, etc. in time and space. In this paper, we have studied the creation of fractal image by the Mandelbrot technique and proposed the interaction method for it to be converted into a variety of forms. By using the proposed method, a variety of image transformation such as printmaking effect, sketch effect, Pop Art effect can be performed, according to clicking a certain fraction on the created fractal image screen by a user mouse. Interactive image generated in this study are expected to be used for trade shows, promotional products, media art design.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.10
• /
• pp.2091-2101
• /
• 1997

Conventional method for fractal image decoding requires high-degree computational complexity in decoding propocess, because of iterated contractive transformations applied to whole range blocks. In this paper, we propose a fast decoding algorithm of fractal image using data depence in order to reduce computational complexity for iterated contractive transformations. Range of reconstruction image is divided into a region referenced with domain, called referenced range, and a region without reference to domain, called unreferenced range. The referenced range is converged with iterated contractive transformations, and the unreferenced range can be decoded by convergence of the referenced range. Thus the unreferenced range is called data dependence region. We show that the data dependence region can be deconded by one transformation when the referenced range is converged. Consequently, the proposed method reduces computational complexity in decoding process by executing iterated contractive transformations for the referenced range only.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.3
• /
• pp.261-266
• /
• 2020

As pioneers of the early video art, Steina Vasulka(1940-) and Woody Vasulka(1937-2019) had lead not only their own experimental arts, but also entire changes of contemporary avant-garde performance, music, and visual art. Two artists invented and developed electronic machines for video image-processing by collaborating with engineers, and performed creative experiment on transformation of digital image. For them, video art is not just a means of documentation. The Vasulkas' artistic practices were not bounded by conventional canons and rules in art world, and preferably were parts of active aesthetic strategies for coexistence of vision of human and vision of machine. Particularly, their video art recognized the video as the key medium in an era where media technology began to dominate the system of communication, and established artist's authority over manipulation of moving image electronically without depending on video camera. In that regard, we can value on their video art. Therefore, the paper reflects on the Vasulkas' art and life which have not yet been studied, and suggests academic interests in the context of their artistic activities and aesthetic strategies.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.35 no.2
• /
• pp.128-133
• /
• 2015

This paper describes the construction of a static 3D ultrasonography image by tracking the radiation beam position during the handy operation of a 1D array probe to enable point-of-care use. The theoretical model of the transformation from the translational and rotational information of the sensor mounted on the probe to the reference Cartesian coordinate system was given. The signal amplification and serial communication interface module was made using a commercially available sensor. A test phantom was also made using silicone putty in a donut shape. During the movement of the hand-held probe, B-mode movie and sensor signals were recorded. B-mode images were periodically selected from the movie, and the gray levels of the pixels for each image were converted to the gray levels of 3D voxels. 3D and 2D images of arbitrary cross-section of the B-mode type were also constructed from the voxel data, and agreed well with the shape of the test phantom.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.40 no.6
• /
• pp.400-407
• /
• 2003

In this paper an optical encryption system, which can decrypt the original image by using the autocorrelation terms of a JTC, is proposed. Unlike the classical JTC, the joint input plane of the proposed system is composed in a frequency domain not a spatial domain, thus it needs only one Fourier transformation. To use like this, the phase component appeared in the output plane of JTC should be considered. We presents the effect of phase and provides the solution. An original image is encrypted to a complex-valued random image. The original image is reconstructed using the autocorrelation terms which is the main drawback of JTC, therefore the proposed system is more suitable for JTC and real time processing. By computer simulation and optical experiment, the analysis for the phase effect and the performance of the proposed system are confirmed.

• Journal of Korea Multimedia Society
• /
• v.7 no.7
• /
• pp.956-966
• /
• 2004

The Korean animation has enjoyed the brisk formation and establishment of its world-class infra for the last several years without unified titles or concepts, under the name of a national strategic project in the age of digital image. It also enjoys its new evaluation as digital animation that it's one of the greatest money making business in the non-education and frivolous culture and has the closest relations with the modern time. A great portion of popular image media has been taken by animation for the last 30 years. In this paper we propose a motion algorithm using an animation technology. It was developed for education purposed and accessible through the internet. For instance, in Cyber Clam Museum, 1000 gesture contents, the visual processes were used to design a screen with a realistic image and create an animation that makes possible show at 360 and every such transformation as translation, rotation, and scaling can be applied in the image interactively for the convenient and effective viewing.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.10
• /
• pp.2441-2449
• /
• 2015

In this digital information era, utilization of images are essential for various media, and the edge is an important characteristical information of an object in images that includes the size, location, direction and etc. Many domestic and international studies are being conducted in order to detect these edge. Existing edge detection methods include Sobel, Prewitt, Roberts, Laplacian, LoG and etc. which apply fixed weight value. As these existing edge detection methods apply fixed weight mask to the image, edge detection characteristic appears slightly insufficient. Accordingly, in order to supplement these problems, this study used bottom-hat transformation from mathematical morphology and opening operation in improving the image and proposed an algorithm that detects for the edge after calculating mask-based gradient. And to evaluate the performance of the proposed algorithm, a comparison was made against the existing Sobel, Roberts, Prewitt, Laplacian, LoG edge detection methods, in illustrating visual images, and similarities were compared by calculating the MSE value based on the standard of each image.