복합 잡음 환경에서 변형된 퍼지 가중치 기반의 스위칭 필터 알고리즘

천봉원,김남호 한국정보통신학회 2023 한국정보통신학회논문지 Vol.27 No.8

With the recent development of AI technology, image processing technology is being used in various fields, such as a smart farms, medical X-ray images, computer tomography(CT), intelligent CCTV, and others. In particular, image separation and object recognition play an important role in AI technology and image analysis but are affected by noise, so the algorithm to remove noise using Type-1 fuzzy function and Type-2 fuzzy function is being studied. In this thesis, for the removal of noise and the preservation of the edge element in a complex noise environment, a switching filter algorithm based on the weighted value of the Type-2 fuzzy algorithm was proposed. In the suggested algorithm, the filtering process was switched by judging noise, and noise in an image was removed by setting a weighted fuzzy value which had been transformed by the features of noise and the characteristics of the pixel value of a local mask. To assess the proposed algorithm's performance, a simulation was conducted in comparison with the existing method. 최근 인공지능 기술의 발전에 따라 스마트 농장, 의료용 X선 영상 및 컴퓨터 단층촬영(CT) 및 지능형 CCTV와 같이 다양한 분야에서 영상처리 기술이 사용되고 있다. 특히 이미지 분할과 객체 인식은 AI 기술과 영상의 분석에서 중요한 역할을 하지만 잡음의 영향을 받기 때문에 Type-1 퍼지 함수 및 Type-2 퍼지 함수를 사용한 잡음제거 알고리즘이 연구되고 있다. 본 논문은 복합잡음 환경에서 잡음제거 및 에지성분의 보존을 위해 Type-2 퍼지 가중치에 기반한 스위칭 필터 알고리즘을 제안한다. 제안한 알고리즘은 잡음 판단을 실행하여 필터링 과정을 스위칭하였으며, 잡음 특성과 국부 마스크의 화소값 특징에 따라 변형된 퍼지 가중치를 설정하여 영상의 잡음을 제거한다. 제안한 알고리즘의 성능을 평가하기 위해 기존 방법과 비교하여 시뮬레이션을 진행하였다.

AWGN 환경에서 퍼지 멤버십 함수에 기반한 잡음 제거 알고리즘

천봉원,김남호,Cheon, Bong-Won,Kim, Nam-Ho 한국정보통신학회 2020 한국정보통신학회논문지 Vol.24 No.12

With the development of IoT technology, various digital equipment is being spread, and accordingly, the importance of data processing is increasing. The importance of data processing is increasing as it greatly affects the reliability of equipment, and various studies are being conducted. In this paper, we propose an algorithm to remove AWGN according to the characteristics of the fuzzy membership function. The proposed algorithm calculates the estimated value according to the correlation between the value of the fuzzy membership function between the input image and the pixel value inside the filtering mask, and obtains the final output by adding or subtracting the output of the spatial weight filter. In order to evaluate the proposed algorithm, it was simulated with existing AWGN removal algorithms, and analyzed using difference image and PSNR comparison. The proposed algorithm minimizes the effect of noise, preserves the important characteristics of the image, and shows the performance of efficiently removing noise.

랜덤 임펄스 잡음 환경에서 에지 성분을 보존하기 위한 스위칭 필터

천봉원,김남호,Cheon, Bong-Won,Kim, Nam-Ho 한국정보통신학회 2020 한국정보통신학회논문지 Vol.24 No.6

Digital image processing has been applied in a wide range of fields due to the development of IoT technology and plays an important role in data processing. Various techniques have been proposed to remove such noise, but the conventional impulse noise canceling methods are insufficient to remove noise of edge components of an image, and have a disadvantage of being greatly affected by random impulse noise. Therefore, in this paper, we propose an algorithm that effectively removes edge component noise in random impulse noise environment. The proposed algorithm calculates the threshold value by determining the noise level and switches the filtering process by comparing the reference value with the input pixel value. The proposed algorithm shows good performance in the existing method, and the simulation results show that the noise is effectively removed from the edge of the image.

랜덤 임펄스 잡음을 제거하기 위한 가중치 스위칭 필터를 이용한 영상 복원 알고리즘

천봉원,김남호,Cheon, Bong-Won,Kim, Nam-Ho 한국정보통신학회 2020 한국정보통신학회논문지 Vol.24 No.5

In the modern society, the use of digital equipment is increasing along with the 4th industrial revolution, and the importance of image and signal processing is increasing. At the same time, research on noise reduction is being actively conducted. In this paper, we propose a switching filter algorithm for random-valued impulse noise cancellation. The proposed algorithm obtains the threshold value by determining the noise level present in the image, and threshold value is compared with the difference between the input pixel value and the reference value, and is used in the weight switching process of the filter. The final output of the filter is estimated by applying a pixel weight and a modified weight median filter according to the switching, and obtains a final output by comparing the estimated value with the input pixel value. To evaluate the performance of the proposed algorithm, we compared it with the existing methods using simulation and PSNR.

유효 화소를 이용한 고밀도 임펄스 잡음 제거 필터 알고리즘

천봉원,김남호,Cheon, Bong-Won,Kim, Nam-Ho 한국정보통신학회 2018 한국정보통신학회논문지 Vol.22 No.10

Digital video equipment is important in the 4th industrial revolution and is widely used in different fields for various purpose. Data of digital video equipment is exposed to noise due to different reasons including user environment and processing and such noise affect output and processing method. This can even cause error, resulting in decreased reliability of the equipment. In this research, it offers algorithm to effectively recover video by removing noise and impulse noise occurring during the process of channel delivery. This proposed algorithm recovers video by exploring valid pixel using directional local mask and noise determination. Then, valid pixel calculated goes through the final output calculation through comparative analysis on estimation. For comparing suggested method and algorithm, simulation is carried out. For checking the function of it, PSNR and profile are analyzed.

AWGN 환경에서 표준편차 및 추정치를 통한 잡음 제거 알고리즘

천봉원,김남호 한국정보통신학회 2018 한국정보통신학회논문지 Vol.22 No.11

The importance of communication and data processing is increasing with the advance of the Fourth IndustrialRevolution. Hence, the importance of video and data processing technologies, which directly influence the accuracy andreliability of equipment, is also increasing. In this research report we propose an algorithm for calculating the final outputby estimating the standard deviation and estimate required for removing AWGN while adapting to changes in thefrequency factors of video. This algorithm calculates the final output by checking an estimated value against the effectivepixel range, which is obtained from the standard deviation of mask factors. Subsequently, the weighted value is computed,taking into account the filter output. To evaluate the functionality of this algorithm, it is compared with themost-commonly used present method through simulation. The simulation results show that the important features of theimage are preserved and efficient noise cancellation performance is demonstrated. 4차 산업혁명의 발전에 따라 통신 및 데이터 처리의 중요성이 높아지고 있으며, 이에 따라 장비의 정확성과 신뢰성에 직접적인 영향을 미치는 영상 및 데이터 처리의 중요성 또한 증가하고 있다. 본 논문에서는 영상의 주파수 성분의 변화에 적응하며 AWGN을 제거하기 위해 표준편차와 추정치의 유추를 통해 최종 출력을 산출하는 알고리즘을제안하였다. 제안한 알고리즘은 마스크 성분의 표준편차를 통해 유효 화소 범위를 설정하여 추정치를 구하며, 가중치를 적용한 후 필터의 출력에 가감하여 최종 출력을 계산한다. 그리고 제안하는 알고리즘의 성능 평가를 위해 시뮬레이션을 통해 기존 방법과 비교 분석하였으며, 시뮬레이션 결과 영상의 중요 특성을 보존하며 효율적인 잡음 제거성능을 보였다.

AWGN 환경에서 고주파 성분을 고려한 잡음 제거 알고리즘

천봉원,김남호,Cheon, Bong-Won,Kim, Nam-Ho 한국정보통신학회 2018 한국정보통신학회논문지 Vol.22 No.6

Recently, interests in the field of image processing have increased with the increased demand for digital imaging devices. However, digital images are damaged by the noise generated by various causes during image processing. Generally in digital imaging devices, noise such as AWGN, etc. is generated and performance and reliability are deteriorated, and various researches are in progress to remove it. Accordingly in the present paper, an algorithm to protect the high frequency components of the images and to efficiently remove AWGN is proposed. The proposed algorithm calculates the final output by adjusting estimate values applied with Gaussian mask and weight values applied according to the local mask distribution. And for performance evaluation of the proposed algorithm, simulations were performed with the existing methods, and the characteristics were compared through PSNR and the processed, enlarged images.

복합 잡음 환경에서 영상의 잡음 성분을 이용한 필터 알고리즘

천봉원,김남호,Cheon, Bong-Won,Kim, Nam-Ho 한국정보통신학회 2019 한국정보통신학회논문지 Vol.23 No.8

최근 다양한 분야에서 디지털 장비의 사용이 증가함에 따라 영상 및 신호처리의 중요성이 높아지고 있다. 하지만 신호의 송수신 과정에서 다양한 이유로 잡음이 발생하며, 이러한 잡음은 시스템의 최종 출력에 큰 영향을 미친다. 본 논문은 S&P 잡음과 AWGN이 혼합된 잡음 환경에서 영상의 잡음 특성을 고려하여 효과적으로 영상을 복원하는 알고리즘을 제안하였다. 제안한 알고리즘은 영상의 잡음 성분 유추와 필터링 마스크 내부의 화소 특성을 고려하여 영상의 특징을 보존하였으며, 입력 화소의 성질에 따라 기준치를 설정하여 이와 유사한 화소들을 선별하여 잡음을 제거하였다. 시뮬레이션 결과 제안한 알고리즘은 우수한 잡음제거 특성을 나타내었으며, 기존 방법들과 비교하기 위해 PSNR 등을 이용하여 비교 및 분석하였다.

AWGN 환경에서 가우시안 분포와 표준편차를 이용한 잡음 제거

천봉원,김남호,Cheon, Bong-Won,Kim, Nam-Ho 한국정보통신학회 2019 한국정보통신학회논문지 Vol.23 No.6

Noise removal is a pre-requisite procedure in image processing, and various methods have been studied depending on the type of noise and the environment of the image. However, for image processing with high-frequency components, conventional additive white Gaussian noise (AWGN) removal techniques are rather lacking in performance because of the blurring phenomenon induced thereby. In this paper, we propose an algorithm to minimize the blurring in AWGN removal processes. The proposed algorithm sets the high-frequency and the low-frequency component filters, respectively, depending on the pixel properties in the mask, consequently calculating the output of each filter with the addition or subtraction of the input image to the reference. The final output image is obtained by adding the weighted data calculated using the standard deviations and the Gaussian distribution with the output of the two filters. The proposed algorithm shows improved AWGN removal performance compared to the existing method, which was verified by simulation.

임펄스 잡음 환경에서 고주파 성분을 보존하기 위한 영상 복원 필터

천봉원,김남호 한국정보통신학회 2019 한국정보통신학회논문지 Vol.23 No.4

Noise removal is one of the required step in processing digital video and there are many researches to develop algorithm that fits with its purpose and environment. However, present impulse noise removal methods are lacking in its function in terms of removing noise in edge and high frequency factors. Therefore, this research has Extended range of masks depending on density to determine noise so that high frequency factors can be preserved. The range of resolution is set based on median and standard deviation of inside resolution after removing impulse noise. afterwards, those resolution within the range are calculated by adding weight to have the final output value. The suggested algorithm has an enhanced function in removing noise in various areas with many edge and high frequency factors than present methods and their functions are compared through simulation. 잡음 제거는 디지털 영상처리 과정에서 필수적으로 이루어지며, 다양한 분야에서 그 목적과 환경에 맞는 알고리즘을 개발하기 위해 많은 연구가 진행되고 있다. 그러나 기존 임펄스 잡음 제거 방법들은 영상의 에지 성분 및 고주파 성분의 잡음 제거에 다소 미흡한 성능을 보이고 있다. 따라서 본 논문에서는 고주파 성분을 보존하기 위해 잡음 판단에 따른 잡음 밀도에 따라 마스크의 범위를 확장하였다. 선택된 마스크는 임펄스 잡음을 제외한 내부 화소의 메디안 값과 표준편차를 기준으로 화소 범위가 설정된다. 그리고 화소 범위에 존재하는 화소는 거리에 따른 가중치를 적용하여 최종 출력 계산에 사용하였다. 제안한 알고리즘은 기존 방법에 비해 영상의 에지 부분 및 고주파 성분이 많은 영역에서 잡음 제거성능이 우수하였으며, 시뮬레이션을 통해 성능을 비교하였다.