• Title/Summary/Keyword: digital low pass filtering

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Real-Time Continuous-Scale Image Interpolation with Directional Smoothing

  • Yoo, Yoonjong;Shin, Jeongho;Paik, Joonki
    • IEIE Transactions on Smart Processing and Computing
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    • v.3 no.3
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    • pp.128-134
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    • 2014
  • A real-time, continuous-scale image interpolation method is proposed based on a bilinear interpolation with directionally adaptive low-pass filtering. The proposed algorithm was optimized for hardware implementation. The ordinary bi-linear interpolation method has blocking artifacts. The proposed algorithm solves this problem using directionally adaptive low-pass filtering. The algorithm can also solve the severe blurring problem by selectively choosing low-pass filter coefficients. Therefore, the proposed interpolation algorithm can realize a high-quality image scaler for a range of imaging systems, such as digital cameras, CCTV and digital flat panel displays.

The Calculation of the Amount of Wear using Digital Filtering (디지털 필터링을 이용한 마멸량 계산)

  • 전종하;구영필;조용주
    • Tribology and Lubricants
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    • v.16 no.2
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    • pp.133-137
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    • 2000
  • A new method to calculate the wear amount using surface profile signal was suggested. It takes advantage of filtering technic to estimate the original surface profile of wear track precisely. The original profile of wear track was estimated by comparing with outside of wear track. The estimated surface profile was well fitted to the original profile assumed unknown.

A Study on the Edge Detection for Road Information based on the IKONOS (IKONOS 영상에서 도로정보추출을 위한 경계검출에 관한 연구)

  • Choi, Hyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.3
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    • pp.593-598
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    • 2006
  • High-resolution satellite imagery has many benefits, compared to aerial photo in the wide area as well as multi-spectral character. So, it can be used well for constructing GIS data when making digital map. This study analysed the possibilities that road information derived automatically from IKONOS can be used for making ITS system or updating digital map of the urban areas where change frequently and producing satellite image map. In this study, Sobel was applied for road edge dectection after low pass filtering. As the results, it's possible for low pass filtering and high pass filtering to be used as the basic data for ITS construction when extracting edge roads and constructs according to the characteristic of high-resolution satellite imagery.

The Characteristics of Computer-Generated Holographic Optical Low-Pass Filter (컴퓨터로 설계한 홀로그램 광 저대역 필터의 특성 분석)

  • 김인길;고춘수;임성우;오용호;이재철
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.12S
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    • pp.1261-1267
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    • 2003
  • Since the grating optical low-pass fillet degrades the resolution of images, we developed a hologram optical low-pass filter that show low degradation of the image and studied its characteristics. We designed the hologram that divides input beam into circular shaped 21 beams with a Monte-Carlo based hologram generation program and calculated its MTE characteristics to compare it with that of a grating filter. The hologram was manufactured through the optical lithography process and attached to a digital imaging device (Zoran 732212) for measurement. The moirfiltering is compared with zone plate images and the resolution loss is measured with USAF resolution chart. The hologram optical low-pass filter showed better characteristics in both moly filtering and resolution.

Real-Time Continuous-Scale Image Interpolation with Directional Smoothing (방향적응적인 연속 비율 실시간 영상 보간 방식 -방향별 가우시안 필터를 사용한 연속 비율 지원 영상 보간 필터-)

  • Yoo, Yoon-Jong;Jun, Sin-Young;Maik, Vivek;Paik, Joon-Ki
    • 한국HCI학회:학술대회논문집
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    • 2009.02a
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    • pp.615-619
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    • 2009
  • A real-time, continuous-scale image interpolation method is proposed based on bi-linear interpolation with directionally adaptive low-pass filtering. The proposed algorithm has been optimized for hardware implementation. The original bi-linear interpolation method has blocking artifact. The proposed algorithm solves this problem using directionally adaptive low-pass filtering. It can also solve the severely problem by selection choosing low-pass filter coefficients. Therefore the proposed interpolation algorithm can realize a high-quality image scaler for various imaging systems, such as digital camera, CCTV and digital flat panel display, to name a few.

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The Calculation of the amount of wear using digital filtering (디지털 필터링을 이용한 마멸량 계산)

  • 전종하;유응대;구영필;조용주
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1999.11a
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    • pp.200-207
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    • 1999
  • A new method for the calculation of a wear amount was suggested. The amount of wear was calculated by the comparison of worn out profile with an estimated original profile. An original profile of wear track was estimated by comparing with outside of wear track. An estimated surface profile was well fitted to the original profile assumed unknown.

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DIGITAL IMAGE PROCESSING AND CLINICAL APPLICATION OF VIDEODENSITOMETER (실험적으로 제작한 Videodensitometer의 디지털 영상처리와 임상적 적용에 관한 연구)

  • Park Kwan-Soo;Lee Sang-Rae
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.22 no.2
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    • pp.273-282
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    • 1992
  • The purpose of this study was to propose the utility which was evaluated the digital image processing and clinical application of the videodensitomery. The experiments were performed with IBM-PC/16bit-AT compatible, video camera(CCdtr55, Sony Co., Japan), an color monitor(MultiSync 3D, NEC, Japan) providing the resolution of 512×480 and 64 levels of gray. Sylvia Image Capture Board for the ADC(analog to digital converter) was used, composed of digitized image from digital signal and the radiographic density was measured by 256 level of gray. The periapical radiograph(Ektaspeed EP-21, Kodak Co., U. S. A) which was radiographed dried human mandible by exposure condition of 70 kVp and 48 impulses, was used for primary X-ray detector. And them evaluated for digitzed image by low and high pass filtering, correlations between aluminum equivalent values and the thickness of aluminum step wedge, aluminum equivalent values of sound enamel, dentin, and alveolar bone, the range of diffuse density for gray level ranging from 0 to 255. The obtained results were as follows: 1. The edge between aluminum steps of digitized image were somewhat blurred by low pass filtering, but edge enhancement could be resulted by high pass filtering. Expecially, edge enhancement between distal root of lower left 2nd molar and alveolar lamina dura was observed. 2. The correlation between aluminum equivalent values and the thickness of aluminum step wedge was intimated, yielding the coefficient of correlation r=0.9997(p<0.00l), the regression line was described by Y=0.9699X+0.456, and coefficient of variation amounting to 1.5%. 3. The aluminum equivalent values of sound enamel, dentin, and alvolar bone were 15.41㎜, 12.48㎜, 10.35㎜, respectively. 4. The range of diffuse density for gray level ranging from 0 to 255 was wider enough than that of photodenstiometer to be within the range of 1-4.9.

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Noise Reduction Methods for the EMG Median Frequency Data in Fatiguing Isotonic Exercise (등장성 운동 시 근전도 중앙주파수 데이터의 잡음 제거 방법)

  • Cho, Sang-Hyun
    • Physical Therapy Korea
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    • v.8 no.4
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    • pp.31-43
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    • 2001
  • 19명의 건강한 성인 남자의 우세팔쪽 위팔두갈래근에서 피로가 생길 때까지 2.4초를 하나의 주기로 팔꿉을 반복적 등장성으로 굽히고 펴서 표면근전도 신호를 얻었다. 처리과정 A 중앙주파수(MDF )는 이 신호의 0.5초 구간을 power spectrum analy sis (PSA)로 계산하였는데 상당량의 잡음이 있었다. 중앙주파수의 잡음 양을 비교하기 위해, 동일한 표면근전도에서 3번까지 신호를 받았다 (2.4초 구간을 PSA로 계산한 처리과정 B, 13 point 로 moving averages한 처리과정 C, digital low pass filter한 처리과정 D). 그리고 나서 그 신호의 주요 주파수 성분을 뽑아내었다. 위의 중앙주파수 자료와 시간간의 회귀직선을 분석하면 초기 중앙주파수, 회귀기울기, 그리고 피로지수와 같은 모수를 얻을 수 있다. 비모수 검정의 하나인 Kendall 기법으로 네 개의 처리과정간의 모수를 비교하였다. 통계결과 잡음이 처리과정 A보다 B, C, D에서 적었고, D에서 가장 적게 나타났다. 중앙주파수를 digital low pass로 여과(filtering)함으로써 앞으로 있게 될 동적 운동 시 근피로 모니터기의 신뢰도를 높일 수 있다.

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Copyright Protection of Digital Image Information based on Multiresolution and Adaptive Spectral Watermark (다중 해상도와 적응성 스펙트럼 워터마크를 기반으로 한 디지털 영상 정보의 소유권 보호)

  • 서정희
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.10 no.4
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    • pp.13-19
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    • 2000
  • With the rapid development of the information communication technology, more and more distribution multimedia data and electronic publishing in the web, has created a need for the copyright protection with authentication of digital information. In this paper, we propose a multi-watermarking adding and adaptive spectral watermark algorithm well adaptive frequency domain of each hierarchical using orthogonal forward wavelet transform(FWT. Numerical test results, created watermarking image robustness not only image transform such as low-pass filtering, bluring, sharpen filtering, wavelet compression but also brightness, contrast gamma correction, histogram equalization, cropping.