• Proceedings of the Korea Information Processing Society Conference
• /
• 2013.05a
• /
• pp.215-218
• /
• 2013

In this paper, we proposed a method for enhancement of color images with sky regions. The input image is converted into HSV space and then sky and non-sky regions are separated. For sky region, saturation enhancement is performed for each pixel based on the enhancement factor calculated from the average saturation of its local neighborhood. On the other hand, for the non-sky region, the enhancement is applied only on the luminance value (V) component of the HSV color image, which is performed in two steps. The luminance enhancement, which is also called as dynamic range compression, is carried out using nonlinear transfer function. Again, each pixel is further enhanced for the adjustment of the image contrast depending upon the center pixel and its neighborhood pixel values. At last, the original H and V component image and enhanced S component image for the sky region, and original H and S component image and enhanced V component image for the non-sky region are converted back to RGB image.

• Korean Journal of Organic Agriculture
• /
• v.22 no.4
• /
• pp.629-643
• /
• 2014

This study analyzed how the brand image elements influenced upon forming the brand trust and the brand loyalty of the 'Sky Green' the joint agricultural product brand Cheonan, Chungnam. The brand image was classified into functional image, symbolical image and origin - associated image. And what element of the brand image element influences upon forming the brand image loyalty by the consumers who are using 'Sky Green'. In the analysis results, the functional image, symbolical image and the image associated with the origin have influenced on forming the brand trust and the brand loyalty. All variables composing the brand image have positive influences on both brand trust and brand loyalty. It means that brand image influences on brand loyalty directly but the greater influence can be exerted through the effects of the parameter of brand trust.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.30 no.1
• /
• pp.14-20
• /
• 2016

The accurate analysis of the outside sky conditions is necessary to increase the efficiency of blind PV system. To conduct the accurate analysis, this paper suggested a method to analyze the sky condition using a specific image processing technique. While a fisheye lens has a wide field-of-views, it causes a large distortion to the sky images. Therefore, this paper calculated the exchange ratio of sky images to consider a lens distortion. As results of the study, there was a difference of 7% to cloud area ratio F4 and F11. Also, it had a different result depending on the position of the cloud.

• Aerospace Engineering and Technology
• /
• v.10 no.2
• /
• pp.163-169
• /
• 2011

This paper introduces a method about water line detection using SAR image. The method includes pre-processing of the SAR image with the threshold of the histogram to recognize the boundary between the water and the landmass area. Finally we applied the image differentiation to detect the water line in the SAR image. The TerraSAR-X and the Cosmo-SkyMed images, which are the high spatial resolution X-band SAR data, are used for the evaluation of our algorithm. The accuracy is verified over the stream line in urban area with the result from the Cosmo-SkyMed.

• Journal of the Institute of Convergence Signal Processing
• /
• v.12 no.1
• /
• pp.7-12
• /
• 2011

In this paper, we propose the technique detecting interest object region effectively in the images from periscope of submarine based on self-generated template. First, we extract the sea-sky line, and divide it into sky and sea area from background region based on the sea-sky line. In each divided background region, the blocks which can be represented in each background region are set as a reference template. After dividing an image into several same size of blocks, we apply multi template matching to the divided search blocks and histogram template to divide the image into object region and background region. Proposed algorithm is adapted to various images in which objects exist in the background of sea and sky. We verified that proposed algorithm performed properly without given informmed prby prior learning.ropso, regardless of the slope of sea-sky line and the locmed p of object based on sea-sky line, we verified that the objects region was segmented effectively from the input image.

• International Journal of Internet, Broadcasting and Communication
• /
• v.15 no.1
• /
• pp.113-119
• /
• 2023

This research analyzed the importance and influence of color expression on psychological and emotional changes of visual perception in the creation of art works. This research takes the element of the sky in the works of Vincent William Van Gogh, a Dutch post-Impressionist representative painter, as the basic research objective to prove the influence of color expression of the same thing on the inner emotional communication of the creator. After synthesizing the contents of previous research and investigation on Van Gogh, this research will summarize the works containing sky elements in Van Gogh's works according to his four creative stages, and select representative works for color analysis and comparison. In this paper, by comparing the colors of the same elements of the sky, we can find Van Gogh's guidance of psychological and emotional changes through the expression of colors in his works, which will play a certain inspiring role in the creation of painting art.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.35 no.4
• /
• pp.319-326
• /
• 2017

SAR (Synthetic aperture radar) images are less affected by the weather compared to optical images and can be obtained at any time of the day. Therefore, SAR images are being actively utilized for military applications and natural disasters. However, because SAR data are in grayscale, it is difficult to perform visual analysis and to decipher details. In this study, we propose a color mapping method using RF (random forest) regression for enhancing the visual decipherability of SAR images. COSMO-SkyMed 2 and WorldView-3 images were obtained for the same area and RF regression was used to establish color configurations for performing color mapping. The results were compared with image fusion, a traditional color mapping method. The UIQI (universal image quality index), the SSIM (structural similarity) index, and CC (correlation coefficients) were used to evaluate the image quality. The color-mapped image based on the RF regression had a significantly higher quality than the images derived from the other methods. From the experimental result, the use of color mapping based on the RF regression for SAR images was confirmed.

• Journal of information and communication convergence engineering
• /
• v.22 no.1
• /
• pp.70-79
• /
• 2024

Bad weather conditions such as haze lead to a significant lack of visibility in images, which can affect the functioning and reliability of image processing systems. Accordingly, various single-image dehazing (SID) methods have recently been proposed. Existing SID methods have introduced effective visibility improvement algorithms, but they do not reflect the image's perspective, and thus have limitations that distort the sky area and nearby objects. This study proposes a new SID method that reflects the sense of space by defining the correlation between image brightness and haze. The proposed method defines the haze intensity by calculating the airlight brightness deviation and sets the weight factor of the depth map by classifying images based on the defined haze intensity into images with a large sense of space, images with high intensity, and general images. Consequently, it emphasizes the contrast of nearby images where haze is present and naturally smooths the sky region to preserve the image's perspective.

• Atmosphere
• /
• v.18 no.1
• /
• pp.1-14
• /
• 2008

The cloud amount, one of the basic parameter in atmospheric observation, have been observed by naked eyes of observers, which is affected by the subjective view. In order to ensure reliable and objective observation, a new algorithm to retrieve cloud amount was constructed using true color images composed of red, green and blue (RGB). The true color image is obtained by the Skyview, an all-sky imager taking pictures of sky, at the Science Building of Yonsei University, Seoul for a year in 2006. The principle of distinguishing clear sky from cloudy sky lies in the fact that the spectral characteristics of light scattering is different for air molecules and cloud. The result of Skyview's algorithm showed about 77% agreement between the observed cloud amount and the calculated, for the error range, the difference between calculated and observed cloudiness, within ${\pm}2$. Seasonally, the best accuracy of about 83% was obtained within ${\pm}2$ range in summer when the cloud amounts are higher, thus better signal-to-noise ratio. Furthermore, as the sky turbidity increased, the error also increased because of increased scattering which can explain the large error in spring. The algorithm still need to be improved in classifying sky condition more systematically with other complimentary instruments to discriminate thin cloud from haze to reduce errors in detecting clouds.

• Korean Institute of Interior Design Journal
• /
• no.37
• /
• pp.110-118
• /
• 2003

Computer simulation is one of the most useful techniques to predict daylighting performance and present visual image. In architectural and interior design practice, the Lightscape is commonly used often to produce persuasive images rather than physically accurate results. Therefore, this study is to validity the Lightscape as daylighting evaluation tool, in particularly performance and realistically visualization. For the purpose, an evaluation test model (12.0m$\times$7.2m$\times$3.0m) of side lighting window with lightshelf was selected. A 1:6 scale plywood physical model was made. Under clear sky condition, illuminance of 84 Interior point were measured. Lightscape was run on a 750 MHz Pentium PC running Windows 2000 under the same sky condition. And a photography image was compared to rendering image. The physical results of interior illuminance were within 8% between the scale model and Lightscape simulation. There were no differences between the photograph image and rendering image by Lightscape in the sight. Lightscape as visualization tool for daylighting performance was validated.