• Title/Summary/Keyword: Image Mask

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Improving Image Fingerprint Matching Accuracy Based on a Power Mask (파워마스크를 이용한 영상 핑거프린트 정합 성능 개선)

  • Seo, Jin Soo
    • Journal of Korea Multimedia Society
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    • v.23 no.1
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    • pp.8-14
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    • 2020
  • For a reliable fingerprinting system, improving fingerprint matching accuracy is crucial. In this paper, we try to improve a binary image fingerprint matching performance by utilizing auxiliary information, power mask, which is obtained while constructing fingerprint DB. The power mask is an expected robustness of each fingerprint bit. A caveat of the power mask is the increased storage cost of the fingerprint DB. This paper mitigates the problem by reducing the size of the power mask utilizing spatial correlation of an image. Experiments on a publicly-available image dataset confirmed that the power mask is effective in improving fingerprint matching accuracy.

Design of Unsharp Mask Filter based on Retinex Theory for Image Enhancement

  • Kim, Ju-young;Kim, Jin-heon
    • Journal of Multimedia Information System
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    • v.4 no.2
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    • pp.65-73
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    • 2017
  • This paper proposes a method to improve the image quality by designing Unsharp Mask Filter (UMF) based on Retinex theory which controls the frequency pass characteristics adaptively. Conventional unsharp masking technique uses blurring image to emphasize sharpness of image. Unsharp Masking(UM) adjusts the original image and sigma to obtain a high frequency component to be emphasized by the difference between the blurred image and the high frequency component to the original image, thereby improving the contrast ratio of the image. In this paper, we design a Unsharp Mask Filter(UMF) that can process the contrast ratio improvement method of Unsharp Masking(UM) technique with one filtering. We adaptively process the contrast ratio improvement using Unsharp Mask Filter(UMF). We propose a method based on Retinex theory for adaptive processing. For adaptive filtering, we control the weights of Unsharp Mask Filter(UMF) based on the human visual system and output more effective results.

High performance γ-ray imager using dual anti-mask method for the investigation of high-energy nuclear materials

  • Lee, Taewoong;Lee, Wonho
    • Nuclear Engineering and Technology
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    • v.53 no.7
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    • pp.2371-2376
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    • 2021
  • As the γ-ray energy increases, a reconstructed image becomes noisy and blurred due to the penetration of the γ-ray through the coded mask. Therefore, the thickness of the coded mask was increased for high energy regions, resulting in severely decreased the performance of the detection efficiency due to self-collimation by the mask. In order to overcome the limitation, a modified uniformly redundant array γ-ray imaging system using dual anti-mask method was developed, and its performance was compared and evaluated in high-energy radiation region. In the dual anti-mask method, the two shadow images, including the subtraction of background events, can simultaneously contribute to the reconstructed image. Moreover, the reconstructed images using each shadow image were integrated using a hybrid update maximum likelihood expectation maximization (h-MLEM). Using the quantitative evaluation method, the performance of the dual anti-mask method was compared with the previously developed collimation methods. As the shadow image which was subtracted the background events leads to a higher-quality reconstructed image, the reconstructed image of the dual anti-mask method showed high performance among the three collimation methods. Finally, the quantitative evaluation method proves that the performance of the dual anti-mask method was better than that of the previously reconstruction methods.

A Study on Image Distortion Correction for Gobo Lighting Optical System (고보 조명 광학계의 이미지 왜곡 보정에 관한 연구)

  • Gyu-Ha Kim;Ji-Hwan Lee;Chang-Hun Lee;Mee-Suk Jung
    • Korean Journal of Optics and Photonics
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    • v.34 no.2
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    • pp.61-65
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    • 2023
  • This paper studies a method of applying pre-distortion to the image mask of the gobo illumination optical system to correct an irradiated image and irradiate a clear image. In the case of the gobo illumination optical system, since it is generally irradiated with a tilt, distortion in the upper and lower directions occurs severely in the image. To solve this problem, the correction coordinates of the image were derived using a proportional equation, and the distortion was corrected by applying them to the image mask. As a result, it was confirmed that the distortion was reduced by 64.5% compared to the case of using the existing image mask.

Hierarchical Correlation-based Anomaly Detection for Vision-based Mask Filter Inspection in Mask Production Lines (마스크 생산 라인에서 영상 기반 마스크 필터 검사를 위한 계층적 상관관계 기반 이상 현상 탐지)

  • Oh, Gunhee;Lee, Hyojin;Lee, Heoncheol
    • IEMEK Journal of Embedded Systems and Applications
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    • v.16 no.6
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    • pp.277-283
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    • 2021
  • This paper addresses the problem of vision-based mask filter inspection for mask production systems. Machine learning-based approaches can be considered to solve the problem, but they may not be applicable to mask filter inspection if normal and anomaly mask filter data are not sufficient. In such cases, handcrafted image processing methods have to be considered to solve the problem. In this paper, we propose a hierarchical correlation-based approach that combines handcrafted image processing methods to detect anomaly mask filters. The proposed approach combines image rotation, cropping and resizing, edge detection of mask filter parts, average blurring, and correlation-based decision. The proposed approach was tested and analyzed with real mask filters. The results showed that the proposed approach was able to successfully detect anomalies in mask filters.

Comparative Study on Sensibility Image to Develop Products of Hahae Mask (하회탈 제품 개발을 위한 소비자의 감성 이미지 비교 연구)

  • 김윤희
    • Science of Emotion and Sensibility
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    • v.7 no.2
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    • pp.123-131
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    • 2004
  • This study has an aim to find out sensible factors of hahae Mask and to be helpful in developing design of products related with cultural products. This study selected and analyzed 32 vocabularies about sensible adjective to evaluate image of hahae Mask. Firstly, this study investigated image of hahae Mask through 32 vocabularies about sensible adjective and categorized 5 factors including 'attractive', 'native', 'interesting', 'active', and 'elaborate'. Secondly, sense had significant differences in 'native' and, 'interesting' based on kinds. Especially yangban Mask has more powerful nativeness than choraengi Mask, and is more interesting than jung Mask, baekjeong Mask, and bune Mask. Thirdly, the materials used in the products of hahae Mask generated differences of sensibility in elaborateness. Especially, elaborate image was emphasized about materials of glass. Fourthly, sensible image of hahae Mask was dependent upon population-statistic characteristics (age, sex, education) and characteristics of products(materials, kinds of Mask). If development of cultural products related with hahae Mask considers five sensible factors based on this study, it will contribute to development of design which coincides with consumers' needs.

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Double Encryption of Binary Image using a Random Phase Mask and Two-step Phase-shifting Digital Holography (랜덤 위상 마스크와 2-단계 위상 천이 디지털 홀로그래피를 이용한 이진 영상 이중 암호화)

  • Kim, Cheolsu
    • Journal of Korea Multimedia Society
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    • v.19 no.6
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    • pp.1043-1051
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    • 2016
  • In this paper, double encryption technique of binary image using random phase mask and 2-step phase-shifting digital holography is proposed. After phase modulating of binary image, firstly, random phase mask to be used as key image is generated through the XOR operation with the binary phase image. And the first encrypted image is encrypted again through the fresnel transform and 2-step phase-shifting digital holography. In the decryption, simple arithmetic operation and inverse Fresnel transform are used to get the first decryption image, and second decryption image is generated through XOR operation between first decryption image and key image. Finally, the original binary image is recovered through phase modulation.

Tool Path Generation for Micro-Abrasive Jet Machining Process with Micro-Mask (마이크로 마스크를 가진 미세입자분사가공을 위한 가공경로의 생성)

  • Kim, Ho-Chan;Lee, In-Hwan;Ko, Tae-Jo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.6
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    • pp.95-101
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    • 2011
  • Micro-abrasive jet machining(${\mu}AJM$) using mask is a fine machining technology which can carve a figure on a material. The mask should have holes exactly same as the required figure. Abrasive particles are jetted into the holes of the mask and it collide with the material. The collision break off small portion of the material. And the ${\mu}AJM$ nozzle should move all over the machining area. However, in general the carving shape is modeled as in a bitmap figure, because it often contains characters. And the mask model is also often modeled from the bitmap image. Therefore, the machining path of the ${\mu}AJM$ also efficient if it can be generated from the bitmap image. This paper suggest an algorithm which can generate ${\mu}AJM$ tool path directly from the bitmap image of the carving figure. And shows some test results and applications.

Real Time Light Intensity Control Algorithm Using Digital Image Mask for the Holographic Data Storage System (홀로그래픽 정보저장장치에서 디지털 이미지 마스크를 이용한 실시간 광량 제어 알고리즘)

  • Kim, Sang-Hoon;Yang, Hyun-Seok;Park, Young-Pil
    • Transactions of the Society of Information Storage Systems
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    • v.6 no.1
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    • pp.1-5
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    • 2010
  • Holographic data storage system(HDSS) has many noise sources - crosstalk, scattering and inter pixel interference, etc. Generally the intensity of a light generated from the laser source has Gaussian distribution and this ununiformity of light also can make the data page to have a low SNR. A beam apodizer is used to make the laser as a flat-top beam but the intensity distribution is not strictly uniform. The intensity of light can be controlled using image mask. In this paper the intensity distribution of light used for HDSS is controlled by a digital image mask. The digital image mask is changed arbitrarily in real-time with suggested algorithm for the HDSS.

Enhanced image detail control using Multi Channel Unsharp Mask Technique (멀티채널 언샤프 마스크 기법을 이용한 영상 세부제어)

  • Cho, Hyun-Ji;Nam, Doohee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.1
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    • pp.165-170
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    • 2015
  • The unsharp mask technique emphasize the boundary of the image by adding the boundary of the original image. This technique improves quality by emphasize its boundaries but produce rough image from image noise. The multi channel unsharp mask is possible to enhance entire contrast of the image by applying at least two channels of unsharp mask. However, There is limitations to strengthen boundaries even if the scale strongly applies the multi channel unsharp mask technique. To solve this problem, linear scaling to nonlinear scaling by applying exponential function to existing multi channel unsharp mask technique. Experimental results show enhanced contrast for desired area because of control scaling in details compared with existing unsharp mask technique.