• 제목/요약/키워드: Image improve

검색결과 3,564건 처리시간 0.033초

프레임 차와 톤 매핑을 이용한 저조도 영상 향상 (Low-light Image Enhancement Based on Frame Difference and Tone Mapping)

  • 정윤주;이영학;심재창;정순기
    • 한국멀티미디어학회논문지
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    • 제21권9호
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    • pp.1044-1051
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    • 2018
  • In this paper, we propose a new method to improve low light image. In order to improve the image quality of a night image with a moving object as much as the quality of a daytime image, the following tasks were performed. Firstly, we reduce the noisy of the input night image and improve the night image by the tone mapping method. Secondly, we segment the input night image into a foreground with motion and a background without motion. The motion is detected using both the difference between the current frame and the previous frame and the difference between the current frame and the night background image. The background region of the night image takes pixels from corresponding positions in the daytime image. The foreground regions of the night image take the pixels from the corresponding positions of the image which is improved by the tone mapping method. Experimental results show that the proposed method can improve the visual quality more clearly than the existing methods.

식생지수 분석의 정확도 향상을 위한 영상융합의 가능성 평가 (Estimation of Probability of Image Fusion to Improve Accuracy of NDVI Analysis)

  • 송영선;손흥규;박정환
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2006년도 춘계학술발표회 논문집
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    • pp.297-304
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    • 2006
  • This paper estimates the probability of image fusion to improve accuracy of NDVl analysis. NDVI has been utilized in monitoring extensive forest or forest fire, and image fusion is a method to improve the resolution of multi-spectra image same resolution as high resolution panchromatic image. In this paper wavelet, PCA, IHS, Brovey and multiplicative method was applied to improve spatial resolution of SPOT-4 satellite image. NDVI images were generated from original and fused images and the correlation coefficient of fused and original image was calculated. The results of their comparison, PCA method showed best performance.

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확대 영상의 몽롱화 현상을 제거하기 위한 보간 알고리즘 연구 (A Study on the Interpolation Algorithm to Improve the Blurring of Magnified Image)

  • 이준호
    • 한국생산제조학회지
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    • 제19권4호
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    • pp.562-569
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    • 2010
  • This paper analyzes the problems that occurred in the magnification process for a fine input image and investigates a method to improve the blurring of magnified image. This paper applies a curve interpolation algorithm in CAD/CAM for the same test images with the existing image algorithm in order to improve the blurring of magnified image. As a result, the nearest neighbor interpolation, which is the most frequently applied algorithm for the existing image interpolation algorithm, shows that the identification of a magnified image is not possible. Therefore, this study examines an interpolation of gray-level data by applying a low-pass spatial filter and verifies that a bilinear interpolation presents a lack of property that accentuates the boundary of the image where the image is largely changed. The periodic B-spline interpolation algorithm used for curve interpolation in CAD/CAM can remove the blurring but shows a problem of obscuration, and the Ferguson' curve interpolation algorithm shows a more sharpened image than that of the periodic B-spline algorithm. For the future study, hereafter, this study will develop an interpolation algorithm that has an excellent improvement for the boundary of the image and continuous and flexible property by using the NURBS, Ferguson' complex surface, and Bezier surface used in CAD/CAM engineering based on the results of this study.

DCT 및 DWT 기반의 손상된 기상레이더 영상 복원 기법 (DCT and DWT based Damaged Weather Radar Image Retrieval)

  • 장봉주;임상훈;김원;노희성
    • 한국멀티미디어학회논문지
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    • 제20권2호
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    • pp.153-162
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    • 2017
  • Today, weather radar is used as a key tool for modern high-tech weather observations and forecasts, along with a wide variety of ground gauges and weather satellites. In this paper, we propose a frequency transform based weather radar image processing technique to improve the weather radar image damaged by beam blocking and clutter removal in order to minimize the uncertainty of the weather radar observation. In the proposed method, DCT based mean energy correction is performed to improve damage caused by beam shielding, and DWT based morphological image processing and high frequency cancellation are performed to improve damage caused by clutter removal. Experimental results show that the application of the proposed method to the damaged original weather radar image improves the quality of weather radar image adaptively to the weather echo feature around the damaged area. In addition, radar QPE calculated from the improved weather radar image was also qualitatively confirmed to be improved by the damage. In the future, we will develop quantitative evaluation scales through continuous research and develop an improved algorithm of the proposed method through numerical comparison.

청소년 대상 신체상 증진 프로그램의 효과에 대한 체계적 문헌 고찰 및 메타분석 (The Effects of Programs on Body-Image Improvement in Adolescents: A Systematic Review and Meta-Analysis)

  • 윤현정;서경산;한달롱
    • 대한간호학회지
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    • 제51권5호
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    • pp.597-616
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    • 2021
  • Purpose: This study's objective was to investigate the effects of programs that improve adolescents' body image, using a systematic review and meta-analysis. Methods: A literature search was performed in eleven electronic databases, using preferred reporting items for systematic reviews and meta-analysis guidelines. Population characteristics, contents of the programs, and measured outcomes were systematically reviewed from 21 selected studies. To estimate the size of the effects, meta-analysis was conducted using Comprehensive Meta-Analysis software. Results: The contents of the programs that aimed to improve body image included physical, psychological, interpersonal, and sociocultural interventions. Sixteen studies were meta-analyzed to estimate the effect size of body-image improvement programs. Results showed that the program for body-image improvement had significant effects on body satisfaction (effect size [ES] = 0.56, 95% confidence interval [CI] = 0.23 to 0.89), and body dissatisfaction (ES = - 0.15, 95% CI = - 0.23 to - 0.08). Conclusion: The program for body image improvement in adolescents includes a combination of physical, psychological, interpersonal relationship, and socio-cultural dimensions. The program that seeks to improve body image appears to be effective at increasing body satisfaction, and at reducing body dissatisfaction in adolescents. Thus, it is necessary to develop and apply multidimensional programs for adolescents to have a positive body image.

Single Low-Light Ghost-Free Image Enhancement via Deep Retinex Model

  • Liu, Yan;Lv, Bingxue;Wang, Jingwen;Huang, Wei;Qiu, Tiantian;Chen, Yunzhong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권5호
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    • pp.1814-1828
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    • 2021
  • Low-light image enhancement is a key technique to overcome the quality degradation of photos taken under scotopic vision illumination conditions. The degradation includes low brightness, low contrast, and outstanding noise, which would seriously affect the vision of the human eye recognition ability and subsequent image processing. In this paper, we propose an approach based on deep learning and Retinex theory to enhance the low-light image, which includes image decomposition, illumination prediction, image reconstruction, and image optimization. The first three parts can reconstruct the enhanced image that suffers from low-resolution. To reduce the noise of the enhanced image and improve the image quality, a super-resolution algorithm based on the Laplacian pyramid network is introduced to optimize the image. The Laplacian pyramid network can improve the resolution of the enhanced image through multiple feature extraction and deconvolution operations. Furthermore, a combination loss function is explored in the network training stage to improve the efficiency of the algorithm. Extensive experiments and comprehensive evaluations demonstrate the strength of the proposed method, the result is closer to the real-world scene in lightness, color, and details. Besides, experiments also demonstrate that the proposed method with the single low-light image can achieve the same effect as multi-exposure image fusion algorithm and no ghost is introduced.

Image Dehazing Enhancement Algorithm Based on Mean Guided Filtering

  • Weimin Zhou
    • Journal of Information Processing Systems
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    • 제19권4호
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    • pp.417-426
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    • 2023
  • To improve the effect of image restoration and solve the image detail loss, an image dehazing enhancement algorithm based on mean guided filtering is proposed. The superpixel calculation method is used to pre-segment the original foggy image to obtain different sub-regions. The Ncut algorithm is used to segment the original image, and it outputs the segmented image until there is no more region merging in the image. By means of the mean-guided filtering method, the minimum value is selected as the value of the current pixel point in the local small block of the dark image, and the dark primary color image is obtained, and its transmittance is calculated to obtain the image edge detection result. According to the prior law of dark channel, a classic image dehazing enhancement model is established, and the model is combined with a median filter with low computational complexity to denoise the image in real time and maintain the jump of the mutation area to achieve image dehazing enhancement. The experimental results show that the image dehazing and enhancement effect of the proposed algorithm has obvious advantages, can retain a large amount of image detail information, and the values of information entropy, peak signal-to-noise ratio, and structural similarity are high. The research innovatively combines a variety of methods to achieve image dehazing and improve the quality effect. Through segmentation, filtering, denoising and other operations, the image quality is effectively improved, which provides an important reference for the improvement of image processing technology.

A Versatile Medical Image Enhancement Algorithm Based on Wavelet Transform

  • Sharma, Renu;Jain, Madhu
    • Journal of Information Processing Systems
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    • 제17권6호
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    • pp.1170-1178
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    • 2021
  • This paper proposed a versatile algorithm based on a dual-tree complex wavelet transform for intensifying the visual aspect of medical images. First, the decomposition of the input image into a high sub-band and low-sub-band image is done. Further, to improve the resolution of the resulting image, the high sub-band image is interpolated using Lanczos interpolation. Also, contrast enhancement is performed by singular value decomposition (SVD). Finally, the image reconstruction is achieved by using an inverse wavelet transform. Then, the Gaussian filter will improve the visual quality of the image. We have collected images from the hospital and the internet for quantitative and qualitative analysis. These images act as a reference image for comparing the effectiveness of the proposed algorithm with the existing state-of-the-art. We have divided the proposed algorithm into several stages: preprocessing, contrast enhancement, resolution enhancement, and visual quality enhancement. Both analyses show the proposed algorithm's effectiveness compared to existing methods.

히스토그램 평형 기법을 이용한 자기 공명 두뇌 영상 콘트라스트 향상 (Magnetic Resonance Brain Image Contrast Enhancement Using Histogram Equalization Techniques)

  • ;이수현
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2019년도 제59차 동계학술대회논문집 27권1호
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    • pp.83-86
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    • 2019
  • Histogram equalization is extensively used for image contrast enhancement in various applications due to its effectiveness and its modest functions. In image research, image enhancement is one of the most significant and arduous technique. The image enhancement aim is to improve the visual appearance of an image. Different kinds of images such as satellite images, medical images, aerial images are affected from noise and poor contrast. So it is important to remove the noise and improve the contrast of the image. Therefore, for this purpose, we apply a median filter on MR image as the median filter remove the noise and preserve the edges effectively. After applying median filter on MR image we have used intensity transformation function on the filtered image to increase the contrast of the image. Than applied the histogram equalization (HE) technique on the filtered image. The simple histogram equalization technique over enhances the brightness of the image due to which the important information can be lost. Therefore, adaptive histogram equalization (AHE) and contrast limited histogram equalization (CLAHE) techniques are used to enhance the image without losing any information.

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모바일 폰 카메라의 이미지 선명도 향상을 위한 적응적 윤곽선 강조 알고리즘 (Algorithm of adaptive edge enhancement to improve image visibility at mobile phone camera)

  • 김경린;최원태;강봉순
    • 융합신호처리학회논문지
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    • 제9권4호
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    • pp.288-294
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    • 2008
  • 본 논문은 모바일 폰 카메라의 이미지 선명도 향상을 위한 윤곽선 강조 알고리즘 개발에 관한 것이다 자연스러운 윤곽선 강조를 위해 이미지 내부의 윤곽선의 특성을 파악하고 각각의 특성에 대하여 가장 적절한 강조 값을 적응적으로 적용할 수 있도록 하였다. 즉, 1차로 2D High Pass Filter를 윤곽선의 특성에 따라 독립적으로 적용하고 2차로 더욱 세분화된 윤곽선 판단 조건에 의해 윤곽선에 따라 적응적으로 윤곽선을 향상시킬 수 있는 과정을 추가하여 이미지의 선명도 향상 효과를 더욱 높일 수 있도록 하였다. 더불어 적응적 윤곽선 강조로 인하여 기존 알고리즘인 이미지 전체에 동일한 2D HPF를 적용해서 나타나는 ringing 현상 등의 부작용들을 상당히 개선할 수 있었다. 개발된 알고리즘의 하드웨어로의 설계 시 하드웨어 자원의 효율성을 고려하여 알고리즘을 최대한 간략하게 개발하였으며 제안된 알고리즘의 simulation을 통하여 기존의 알고리즘과 비교하여 개선된 결과를 확인하였다.

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