• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.7
• /
• pp.1393-1398
• /
• 2004

Image is degraded by several causes such as the process of acquisition, storage and transmission. To restore those images, many researches have been continued. Centrally methods to restore degraded image by AWGN(additive white gaussian noise) a.e mean filter and wiener filter. Especially, mean filter is superior in noise reduction of area that is a small change of luminosity. But mean filter brings about the effect smoothing edge components of the image, because it does'nt consider characteristics of the image. So in this paper we propose an image restoration method compounding respective images adding established weights, after filtering with mean filter and powerful wiener filter in both improvement of contrast and preservation of edge components.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.5
• /
• pp.1064-1070
• /
• 2012

Nowadays, image processing has been applied in a variety of fields. In order to preserve the high quality of visual the degradation phenomenon for images should be removed. Noise is one of the representative elements cause of the degradation phenomenon and AWGN(additive white Gaussian noise) always damages images. In this paper, an mixed filter algorithm, which is based on parallel denoising method, is proposed to suppress AWGN. This algorithm parallels the spatial domain wiener filter and the wavelet domain thresholding method which thresholding function is selected based on scale level. The proposed modified thresholding function which considers the dependency between parent and child coefficient performs well on suppressing noise.

• Korean Institute of Interior Design Journal
• /
• v.25 no.3
• /
• pp.82-89
• /
• 2016

This study investigated the preservation status of wooden architectural heritages, designated as Chungcheongbuk-do designated heritage in Jecheon. The purpose of this paper is to find the damage cause and the preservation method of wooden architectural heritages. It was conducted using the research methods of the existing literature and field survey to compare a current status of wooden architectural heritages. The result are as followings. Firstly, it was found the problems of a break, a damage, etc. in the platform and the problems of a cracking, an exfoliation, a corrosion, a warp, etc. in the wall. And, it was found a cracking of the beam(梁) and a roof tile(瓦), a falling of Angto(仰土), a sagging roof, etc. in the roof. Secondly, the damage causes of wooden architectural heritages were mostly caused by the physical limitations of the materials. And, it was caused by a rainwater, a subsidence of ground settlement, a destruction of waterproof membrane, etc. Lastly, the repair methods are making a quicklime layer in the soil mound on a cracking and an exfoliation part, a resin treatment or strut operation on a corrosion part of column, etc.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.05a
• /
• pp.577-580
• /
• 2010

This paper proposes a new algorithm for flicker reduction. Flicker is defined as unwanted luminance fluctuation in the image sequences. As the flicker degrades the performance of motion estimation or segmentation of the objects, it should be corrected before further processing. In this paper, we model the flicker effects as a linear system with gain and offset parameter and propose the new algorithm for flicker reduction. The proposed algorithm considers gain and offset parameter separately, and stabilizes the luminance fluctuation based on these parameters. We show the performance of the proposed method by testing on the sequence with artificially added luminance flicker and real sequence with object motion.

• 보존과학연구
• /
• s.34
• /
• pp.64-81
• /
• 2013

It is not easy to define the priority criteria of the need of conservation treatment for stone cultural heritage, although many of them have been treated and restored over the past decade. This study approached the correlation between damage grade and the need of conservation treatment based on damage diagnosis of stone cultural heritage carried out from 2001 to 2005. The number of Third-graded (from First to Fifth-grade) stone heritage in deterioration was the highest among state-designated stone cultural heritage. The Fourth-graded stone cultural heritage (143 in total) was mostly influenced by high physiochemical deterioration, whereas the Fifth-graded ones (61 in total) was dominantly affected by biological colonization. It was estimated that total 211 stone cultural heritage were treated for conservation and restoration from 2002 to 2011. They were usually cleaned (total 134, 26.1%), joined and consolidated, and maintenance works as shelter construction, drainage installation and surrounding cleaning were carried out for some of them. The number of conservation intervention increased with the high deterioration grade, and the case number of metamorphic and sedimentary rocks. By age, the stone cultural heritage in Three-kingdom Period were treated the most, and other heritage in Unified Shilla, Goryeo and Joseon showed an approximate ratio. The stone cultural heritage fallen in the fifth-grade in deterioration demonstrated the highest ratio, approximately 80% of conservation intervention. These results can be used as preliminary data to define the emergency criteria for conservation intervention policy.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.05a
• /
• pp.932-935
• /
• 2015

Recently, the image system is utilized in several fields due to the development of multimedia technology. However, the noise occurs according to various causes in the process of image data processing. The noises added to the image include several types according to the cause and shape, and the salt and pepper noise is one of the typical noise types. Thus, this paper proposed the median filter algorithm using the estimated mask in order to remove the salt and pepper noise effectively and also compared this algorithm with the current methods using PSNR(peak signal to noise ratio) as a criterion of judgment.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.4
• /
• pp.949-956
• /
• 2014

Recently, with the development of hardware and software technology related with image information delivery, the demand for various multimedia service has increased. But, the process of treating, sending, and storing image signals generates image degradation by various external causes. The main cause of image degradation is noise. image is mostly damaged by AWGN (additive white Gaussian noise). Therefore, there have been active researches on noise elimination. This paper, to reduce the effects of AWGN added to the image, suggests a noise-eliminating algorithm which is excellent in low-frequency and high-frequency characteristics in space. And, this paper, through simulation techniques, compared the result of the suggested algorithm with those of the existing methods. And, to evaluate the performance of it, PSNR (peak signal to noise ratio) was used.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2012.10a
• /
• pp.959-962
• /
• 2012

In the process of image acquisition, transmission and storage, image degradation occurs due to various reason, the mainly reason is noise. To restore basic methods used images of impulse noise pollution by SM, AF, CWMF. In this paper, using the modified filter to remove impulse noise. The method consists of detection and noise filtering of the noise signal. For a non-noise signal is intact, the noise signal is filtered according to the algorithm. And then through the simulation is compared with known basic methods, with PSNR as judged by reference.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.05a
• /
• pp.671-673
• /
• 2016

In image data, noise occurs due to various external factors in the process of obtaining and transmitting. There are various types of noise according to the cause and form and research to remove this noise is being continued. Therefore the study suggested a way to filter to restore images damaged by salt and pepper noise which preserves non-noise signal and processes noise signal by expanding mask size according to the local mask noise density. In addition, as an objective evaluation standard of improvements, the study used PSNR(peak signal to noise ratio) to compare with previous methods.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.5
• /
• pp.1251-1256
• /
• 2010

In the transmitting process of image signal processing system, there are several different causes of degradation that have been occuring. The main cause of degradation is attributed to the noise. The most representive method of removing noise of image, which is caused by impulse noise environment, is using the SM filter. At edge, the filter has a special feature which has a tendency to decrease. As a result, we proposed a nonlinear filter using the form of mask and the probability of the impulse noise to restore the image considering edge quality in the impulse noise environment. And through the simulation, we compared with the existings and capabilities.