• Journal of the Optical Society of Korea
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• v.5 no.3
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• pp.117-122
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• 2001

A three-dimensional (3D) display system based on computer-generated integral photography (CGIP) is proposed and its feasibility is discussed. Instead of the pickup process in conventional IP, the elemental images of imaginary objects are computer-generated. Using these images, we observed autostereoscopic 3D images in full color and full parallax. The lateral and depth resolutions of the integrated images are limited by some factors such as the image position, object thickness, the lens width, and the pixel size of display panel.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.1
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• pp.31-38
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• 2002

We measured a 3-dimensional images of the light emitted from plasma display panel(PDP) by using newly proposed scanned point detecting system. In the panel without phosphor, as we scan from the rear glass to the front glass, the detected light intensity increases and the light intensity detected in the inside edge of the ITO electrodes shows the stronger intensity than others. The light intensity detected between the barrier ribs shows the largest value of brightness. Also, as the sustain voltage increases, the detected light intensity increases. In the panel with phosphor, the intensity of light detected at barrier rib shows the stronger light intensity than rear plate. Therefore, the phosphor of barrier rib is very important. From these results the 3-dimensional measurement is necessary to understand exactly the discharge phenomenon in the PDP cell.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.16 no.2
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• pp.131-139
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• 2016

Recognition of human motions has become a main area of computer vision due to its potential human-computer interface (HCI) and surveillance. Among those existing recognition techniques for human motions, head detection and tracking is basis for all human motion recognitions. Various approaches have been tried to detect and trace the position of human head in two-dimensional (2D) images precisely. However, it is still a challenging problem because the human appearance is too changeable by pose, and images are affected by illumination change. To enhance the performance of head detection and tracking, the real-time three-dimensional (3D) data acquisition sensors such as time-of-flight and Kinect depth sensor are recently used. In this paper, we propose an effective feature extraction method, called adaptive local binary pattern (ALBP), for depth image based applications. Contrasting to well-known conventional local binary pattern (LBP), the proposed ALBP cannot only extract shape information without texture in depth images, but also is invariant distance change in range images. We apply the proposed ALBP for head detection and tracking in depth images to show its effectiveness and its usefulness.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1997.11a
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• pp.79-85
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• 1997

Virtual holography is a methodology of synthesizing apparent three-dimensional images from two-dimensional photographs. Since the input is photographic images of real objects, the degree of realism exceeds that offered by any computer-aided design software. The three-dimensional appearance is given in real-time by images from arbitrary viewing directions. If infinitely many photographs were taken and pasted together, virtual holography would have been trivial. But, the (infinite) storage requirement would prohibit such an attempt.

• Journal of Korean Dental Science
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• v.12 no.2
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• pp.39-47
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• 2019

Purpose: This study was aimed to evaluate whether the size of the changed area included in the registration area affects the validity of superimposition in three-dimensional (3D) images. Materials and Methods: Ten mannequin heads which were sectioned to simulate maxillary and mandibular setback surgery were used. A total of 30 images, including 10 initial images, 10 images after moving both middle and lower faces, and 10 images after moving only lower face, were obtained. The 9 landmarks which consisted of the bilateral and midline landmarks of the upper, middle, and lower faces respectively were used. Each 3D image obtained after simulation was superimposed 3 times according to the different 3 registration areas. The one-way ANOVA and posthoc analysis were performed. Result: In the case of moving middle and lower faces, there was no significant difference in all markers when superimposition was performed based on no changed area and forehead area. However, in the case of superimposition by the whole face, all measurements showed a significant difference (P<0.05) except for Pn (P>0.05). In the case of moving only lower face, all measurements did not show a significant difference regardless of the registration area. Conclusion: The validity of 3D superimposition in 3D images could be affected by the size of changed areas included in the registration area. In the postoperative evaluation of mandibular surgery, the registration area does not affect the accuracy of the 3D superposition. However, after the maxilla-mandibular surgery, the registration area should be set except for the changed soft tissue.

• Proceedings of the ESK Conference
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• 1996.04a
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• pp.168-185
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• 1996

In this research, an investigation of the eye movement was performed when the objects perceived by the eye are three-dimensional objects, two dimensional images, and three dimensional image. This investigation was done by observing the EOG(Electro-oculogram) waves which were achived from experiments. The observed waves were categorized into several groups. Differences among the waves were analyzed for each object and image perceived by the eye. In order to obtain waves to be analyzed, two kinds of experiments were performed. In each experiments, the saccadic eye movement and the smooth pusuit eye movement was considered as an independent variable individually. Waves obtained from the experiments were categorized into 4 types(Wave1, Wave2, Wave3, Wave4) depending on their characteristics. Unlike from the other images, three dimensional image was revealed as a key factor for the active movement of the eye. Futhermore, a unique eye movement was observed in the case of three dimensional image where the focus of the eye was achived in three steps.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.11
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• pp.2799-2804
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• 2014

In this paper, we suggest three-dimensional information extraction map system using integral imaging technique. Integral imaging can record multiple elemental images with different perspectives using a 2D image acquisition device with lenslet array. Using these images, integral imaging can obtain 3D information and display 3D image. In this paper, the position difference between elemental images can be obtained using summation of absolute difference (SAD), and then 3D information can be extracted. Therefore, this technique can find the height information of 3D objects.

• Imaging Science in Dentistry
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• v.42 no.1
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• pp.25-33
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• 2012

Purpose : This study was performed to determine the accuracy of linear measurements on three-dimensional (3D) images using multi-detector computed tomography (MDCT) and cone-beam computed tomography (CBCT). Materials and Methods : MDCT and CBCT were performed using 24 dry skulls. Twenty-one measurements were taken on the dry skulls using digital caliper. Both types of CT data were imported into OnDemand software and identification of landmarks on the 3D surface rendering images and calculation of linear measurements were performed. Reproducibility of the measurements was assessed using repeated measures ANOVA and ICC, and the measurements were statistically compared using a Student t-test. Results : All assessments under the direct measurement and image-based measurements on the 3D CT surface rendering images using MDCT and CBCT showed no statistically difference under the ICC examination. The measurements showed no differences between the direct measurements of dry skull and the image-based measurements on the 3D CT surface rendering images (P>.05). Conclusion : Three-dimensional reconstructed surface rendering images using MDCT and CBCT would be appropriate for 3D measurements.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.646-651
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• 2003

Quantitative performance test on the conventional 2D-PIV and the hybrid angular 3D-PIV (Stereoscopic PIV) was carried out. LES Data sets on an impinging jet which are provided on the webpage(http://www.vsj.or.jp/piv) for the PIV Standard Project were used for the generation of virtual images. The generated virtual images were used for the 2D-PIV and 3D-PIV measurements. The measurement results showed that the results obtained by 2D-PIV on average values are closer to the LES data than those obtained by 3D-PIV, but the turbulent properties obtained by 2D-PIV are largely underestimated than those obtained by 3D-PIV.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.11
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• pp.1315-1321
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• 2004

Quantitative performance test on the conventional 2D-PIV and the hybrid angular 3D-PIV(Stereoscopic PIV) was carried out. LES Data sets on an impinging jet which are provided on the webpage(http://www.vsj.or.jp/piv) for the PIV Standard Project were used for the generation of virtual images. The generated virtual images were used for the 2D-PIV and 3D-PIV measurements test. It has been shown that the results obtained by 2D-PIV on average values are slightly closer to the LES data than those obtained by 3D-PIV, but the turbulent properties obtained by 2D-PIV are largely underestimated than those obtained by 3D-PIV.