• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.2
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• pp.157-163
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• 1991

The author has evaluated the panoramic image of the maxillary sinus according to the skull position. The lead foils were attached to the five walls of the maxillary sinus and the inferior turbinate individually. The skull was located in three positions; standard position, 20㎜ forward position and chin-down position. The obtained results were as follows: 1. In standard position, the medial wall was superimposed upon most of the panoramic antral image. The anterior wall and the posterolateral wall were superimposed upon the medial half and the lateral third respectively. 2. In forward position, the width of the panoramic antral image was diminished generally. The anterior wall was superimposed upon most of the panoramic antral image and the posterolateral wall appeared narrowly at the most lateral portion of the panoramic antral image. 3. In chin-down position, there was no significant difference in comparison to the standard position. 4. Inferior turbinate was not superimposed upon the panoramic antral image.

• Imaging Science in Dentistry
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• v.54 no.1
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• pp.57-62
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• 2024

Purpose: This report presents a unique case featuring real, ghost, and pseudo-ghost images on the panoramic radiograph of a patient wearing earrings. It also explains the formation of these images in an easy-to-understand manner. Materials and Methods: One real image and two ghost images appeared on each side of a panoramic radiograph of a patient wearing earrings on both sides. Of the two ghost images on each side, one was considered a typical ghost image and the other was considered a ghost-like real image (pseudo-ghost image). The formation zones of the real, double, and ghost images were examined based on the path and angles of the X-ray beam from the Planmeca ProMax. To simulate the pseudo-ghost and typical ghost images on panoramic radiography, a radiopaque marker was affixed to the right mandibular condyle of a dry mandible, and the position of the mandible was adjusted accordingly. Results: The center of rotation of the Planmeca ProMax extended beyond the jaw area, and the area of double image formation also reached beyond the jaw. The radiopaque-marked mandibular condyle, situated in the outwardly extending area of double image formation, exhibited triple images consisting of real, double (pseudo-ghost), and ghost images. These findings helped to explain the image formation associated with the patient's earrings observed in the panoramic radiograph. Conclusion: Dentists must understand the characteristics and principles of the panoramic equipment they use and apply this understanding to taking and interpreting panoramic radiographs.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.355-356
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• 2007

This paper proposes a new panoramic image synthesis method using flash and no-flash image pairs, which reduces undesirable artifacts. Generally, in panoramic images, it is difficult to determine to use a flash in indoor environment. A flash image has unwanted artifacts such as hot spots and tunnel effect whereas a no-flash image also has artifacts like glass reflection. We derive cross projection tensors using flash and no-flash image pairs and transform the gradient field of a no-flash image using them. The image reconstructed from the modified gradient provides enhanced results, which are applied to synthesis of panoramic images. The proposed method can provide a better panoramic image than the conventional method. Experimental results show the effectiveness of the proposed method.

• Journal of the Korea Society of Computer and Information
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• v.12 no.3
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• pp.67-73
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• 2007

This paper presents a panoramic reference image generation based automatic algorithm for moving objects detection robust to illumination variations under moving camera. Background image is generated by rotating the fixed the camera on the tripod horizontally. aligning and reorganizing this images. In generation of the cylindrical panoramic image, most of previous works assume the static environment. We propose the method to generating the panoramic reference image from dynamic environments in this paper. We develop an efficient approach for panoramic reference image generation by using accumulated edge map as well as method of edge matching between input image and background image. We applied the proposed algorithm to real image sequences. The experimental results show that panoramic reference image generation robust to illumination variations can be possible using the proposed method.

• Journal of information and communication convergence engineering
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• v.10 no.4
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• pp.411-419
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• 2012

This paper proposes a semi-automatic image-based approach for 3-dimensional (3D) modeling of buildings along streets. Image-based urban 3D modeling techniques are typically based on the use of aerial and ground-level images. The aerial image of the relevant area is extracted from publically available sources in Google Maps by stitching together different patches of the map. Panoramic images are common for ground-level recording because they have advantages for 3D modeling. A panoramic video recorder is used in the proposed approach for recording sequences of ground-level spherical panoramic images. The proposed approach has two advantages. First, detected camera trajectories are more accurate and stable (compared to methods using multi-view planar images only) due to the use of spherical panoramic images. Second, we extract the texture of a facade of a building from a single panoramic image. Thus, there is no need to deal with color blending problems that typically occur when using overlapping textures.

• Proceedings of the Korea Contents Association Conference
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• 2006.05a
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• pp.431-435
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• 2006

Panoramic Image provides wider field of view than image from acquisition equipment such as a camera and provides realism and immersion to users compared with single image. Cubic panoramic image provides three dimensional access zooming and rotating in top, bottom, left and right directions. But we require commercial softwares to make a panoramic image and can see distorted images in top and bottom direction. This paper presents a method that constructs cubic panoramic virtual reality image using Apple QuickTimeVR's cubic data structure without any commercial software to make realistic image of top and bottom direction in cubic panoramic virtual reality space.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.155-156
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• 2010

`Panoramic image' is called generally 'mosaic image', to create a new image by matching the number of relevant images. In this paper, we are entering data through the camera. Therefore, perspective model was used for recognition of camera parameters, minimizing the discrepancies by proposing measure of discrepancy between the frames. In addition, how to create panoramic images is proposed by fixed reference and time-varying reference in order to create panoramic images.

• Journal of the Institute of Convergence Signal Processing
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• v.3 no.3
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• pp.41-46
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• 2002

We generally used electric optical sensors in order to detect and identify sea objects efficiently. However due to the limitation of view-angle, the region acquired from the sense is restricted. So it is necessary to generate panoramic image from sea images acquired from pan-tilt camera. Previous mosaicing method is not able to generate panoramic image for sea environment because intensity is similar to all region and time varying. In this paper, we proposed new algorithm for generating high-resolution panoramic image on sea environment. Proposed algorithm use single-view point model, applying mosaicing result in feature environment to in sea environment, we overcame the limitation of previous method. In the result of virtual and real experiment, we showed that proposed algorithm is efficient for generating sea panoramic image.

• Journal of Korea Game Society
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• v.17 no.6
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• pp.153-164
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• 2017

In spherical panoramic images, SURF, a feature description method for planar patterns, does not work correctly due to heavy spherical distortion. Since a plane pattern is distorted in a spherical image, the pattern search and replacement in a spherical panoramic image should be treated differently from the case of the planar image. This paper proposes a planar texture replacement method, which transforms a spherical panoramic image into a cubemap panoramic image, searches a pattern using SURF, replaces a plane pattern, and then converts it into a spherical panoramic image.

• Journal of the Optical Society of Korea
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• v.14 no.3
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• pp.245-259
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• 2010

We have developed mathematically precise image-processing algorithms for extracting panoramic images from fisheye images. Furthermore, we have successfully built a DSP-based panoramic camera employing single fisheye lens.