The Experts below are selected from a list of 2400 Experts worldwide ranked by ideXlab platform
Giovanni Ramponi - One of the best experts on this subject based on the ideXlab platform.
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hsv domain enhancement of high contrast images power laws and Unsharp Masking for bounded and circular signals
International Conference on Computer Vision Theory and Applications, 2018Co-Authors: Alfredo Restrepo Palacios, Stefano Marsi, Giovanni RamponiAbstract:DEEI, University of Trieste, Via Valerio 10, Trieste, Italyarestrepo@units.it, marsi@units.it, ramponi@units.itKeywords: Tone mappings, gamma correction, Unsharp Masking, circular processing, color enhancement.Abstract: We present techniques for performing luminance mapping and Unsharp-Masking-like processing on digitalimages; they are specifically designed for their application on bounded and on circular signals. We studythe effect of gamma correction on contrast and develop an adaptive technique for luminance and contrastcorrection. We use the proposed tools for the enhancement of high contrast color images.
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VISAPP (2) - HSV-DOMAIN ENHANCEMENT OF HIGH-CONTRAST IMAGES - Power Laws and Unsharp Masking for Bounded and Circular Signals
2018Co-Authors: Alfredo Restrepo Palacios, Stefano Marsi, Giovanni RamponiAbstract:DEEI, University of Trieste, Via Valerio 10, Trieste, Italyarestrepo@units.it, marsi@units.it, ramponi@units.itKeywords: Tone mappings, gamma correction, Unsharp Masking, circular processing, color enhancement.Abstract: We present techniques for performing luminance mapping and Unsharp-Masking-like processing on digitalimages; they are specifically designed for their application on bounded and on circular signals. We studythe effect of gamma correction on contrast and develop an adaptive technique for luminance and contrastcorrection. We use the proposed tools for the enhancement of high contrast color images.
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Image enhancement via adaptive Unsharp Masking
IEEE transactions on image processing : a publication of the IEEE Signal Processing Society, 2000Co-Authors: A. Polesel, Giovanni Ramponi, V.j. MathewsAbstract:This paper presents a new method for Unsharp Masking for contrast enhancement of images. The approach employs an adaptive filter that controls the contribution of the sharpening path in such a way that contrast enhancement occurs in high detail areas and little or no image sharpening occurs in smooth areas.
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a rational Unsharp Masking method for tv applications
International Conference on Image Processing, 1999Co-Authors: G Scognamiglio, Giovanni Ramponi, A Rizzi, L AlbaniAbstract:In this paper, we present an Unsharp Masking-based approach for edge enhancing for TV application. The proposed scheme enhances the true details, limits the overshoot near sharp edges and attenuates the temporal artifacts which are visible in an image sequence. Simulations show that the processed sequence presents sharp edges which make it more pleasant to the human eye. Moreover, the amount of noise and nonhomogeneities in the sequence are clearly reduced.
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A cubic Unsharp Masking technique for contrast enhancement
Signal Processing, 1998Co-Authors: Giovanni RamponiAbstract:Abstract The cubic Unsharp Masking method is introduced in this paper. It is demonstrated, through both a statistical study and some computer simulations, that the proposed method has a much reduced noise sensitivity with respect to the linear Unsharp Masking technique and it permits to obtain perceptually pleasant results. The proposed operator also compares favourably with other algorithms which recently have been studied to improve the behaviour of the Unsharp Masking approach.
Moncef Gabbouj - One of the best experts on this subject based on the ideXlab platform.
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Unsharp Masking based approach for color image processing
European Signal Processing Conference, 1998Co-Authors: Faouzi Alaya Cheikh, Lazhar Khriji, Moncef GabboujAbstract:In this paper, we present an Unsharp Masking-based approach for noise smoothing and edge enhancing. And apply it to color image processing. The proposed structure is similar to the conventional Unsharp Masking structure, however, a nonlinear function is added to control the behavior of the operator. The proposed scheme enhances the true details, limits the overshoot near sharp edges and attenuates the noise in flat areas. Moreover the use of the control function eliminates the need for the subjective coefficient λ used in the conventional Unsharp Masking technique. Simulations show that the processed image presents sharp edges which makes it more pleasant to the human eye. Moreover, the amount of noise in the image is clearly reduced.
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EUSIPCO - Unsharp Masking-based approach for color image processing
1998Co-Authors: Faouzi Alaya Cheikh, Lazhar Khriji, Moncef GabboujAbstract:In this paper, we present an Unsharp Masking-based approach for noise smoothing and edge enhancing. And apply it to color image processing. The proposed structure is similar to the conventional Unsharp Masking structure, however, a nonlinear function is added to control the behavior of the operator. The proposed scheme enhances the true details, limits the overshoot near sharp edges and attenuates the noise in flat areas. Moreover the use of the control function eliminates the need for the subjective coefficient λ used in the conventional Unsharp Masking technique. Simulations show that the processed image presents sharp edges which makes it more pleasant to the human eye. Moreover, the amount of noise in the image is clearly reduced.
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directional Unsharp Masking based approach for color image enhancement
NMBIA, 1998Co-Authors: Faouzi Alaya Cheikh, Moncef GabboujAbstract:In this paper, we present an Unsharp Masking-based approach for noise smoothing and edge enhancing in multichannel images. The proposed structure is similar to the conventional Unsharp Masking structure, however, the enhancement is allowed only in the direction of maximal change and the enhancement parameter is computed as a nonlinear function of the rate of change. The proposed scheme enhances the true details, limits the overshoot near sharp edges and attenuates noise in flat areas. Moreover the use of the control function eliminates the need for the subjective coefficient λ used in the conventional Unsharp Masking technique.
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NMBIA - Directional Unsharp Masking-Based Approach for Color Image Enhancement
Noblesse Workshop on Non-Linear Model Based Image Analysis, 1998Co-Authors: Faouzi Alaya Cheikh, Moncef GabboujAbstract:In this paper, we present an Unsharp Masking-based approach for noise smoothing and edge enhancing in multichannel images. The proposed structure is similar to the conventional Unsharp Masking structure, however, the enhancement is allowed only in the direction of maximal change and the enhancement parameter is computed as a nonlinear function of the rate of change. The proposed scheme enhances the true details, limits the overshoot near sharp edges and attenuates noise in flat areas. Moreover the use of the control function eliminates the need for the subjective coefficient λ used in the conventional Unsharp Masking technique.
Hans-peter Seidel - One of the best experts on this subject based on the ideXlab platform.
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a perceptual evaluation of 3d Unsharp Masking
electronic imaging, 2009Co-Authors: Matthias Ihrke, Tobias Ritschel, Kaleigh Smith, Thorsten Grosch, Karol Myszkowski, Hans-peter SeidelAbstract:Much research has gone into developing methods for enhancing the contrast of displayed 3D scenes. In the current study, we investigated the perceptual impact of an algorithm recently proposed by Ritschel et al. 1 that provides a general technique for enhancing the perceived contrast in synthesized scenes. Their algorithm extends traditional image-based Unsharp Masking to a 3D scene, achieving a scene-coherent enhancement. We conducted a standardized perceptual experiment to test the proposition that a 3D Unsharp enhanced scene was superior to the original scene in terms of perceived contrast and preference. Furthermore, the impact of different settings of the algorithm's main parameters enhancement-strength (λ) and gradient size (σ) were studied in order to provide an estimate of a reasonable parameter space for the method. All participants preferred a clearly visible enhancement over the original, non-enhanced scenes and the setting for objectionable enhancement was far above the preferred settings. The effect of the gradient size σ was negligible. The general pattern found for the parameters provides a useful guideline for designers when making use of 3D Unsharp Masking: as a rule of thumb they can easily determine the strength for which they start to perceive an enhancement and use twice this value for a good effect. Since the value for objectionable results was twice as large again, artifacts should not impose restrictions on the applicability of this rule.
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3D Unsharp Masking for scene coherent enhancement
ACM Transactions on Graphics, 2008Co-Authors: Tobias Ritschel, Kaleigh Smith, Matthias Ihrke, Thorsten Grosch, Karol Myszkowski, Hans-peter SeidelAbstract:We present a new approach for enhancing local scene contrast by Unsharp Masking over arbitrary surfaces under any form of illumination. Our adaptation of a well-known 2D technique to 3D interactive scenarios is designed to aid viewers in tasks like understanding complex or detailed geometric models, medical visualization and navigation in virtual environments. Our holistic approach enhances the depiction of various visual cues, including gradients from surface shading, surface reflectance, shadows, and highlights, to ease estimation of viewpoint, lighting conditions, shapes of objects and their world-space organization. Motivated by recent perceptual findings on 3D aspects of the Cornsweet illusion, we create scene coherent enhancements by treating cues in terms of their 3D context; doing so has a stronger effect than approaches that operate in a 2D image context and also achieves temporal coherence. We validate our Unsharp Masking in 3D with psychophysical experiments showing that the enhanced images are perceived to have better contrast and are preferred over unenhanced originals. Our operator runs at real-time rates on a GPU and the effect is easily controlled interactively within the rendering pipeline.
Yicong Zhou - One of the best experts on this subject based on the ideXlab platform.
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plip based Unsharp Masking for medical image enhancement
International Conference on Acoustics Speech and Signal Processing, 2016Co-Authors: Zhou Zhao, Yicong ZhouAbstract:Medical image enhancement is an effective tool to improve visual quality of digital medical images. In this paper, we propose a new Unsharp Masking scheme for medical image enhancement. It embeds the PLIP multiplication into the Unsharp Masking framework. Experimental results demonstrate that the proposed method can effectively enhance the overall contrast and edges of medical images while suppressing background noise.
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ICASSP - PLIP based Unsharp Masking for medical image enhancement
2016 IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP), 2016Co-Authors: Zhou Zhao, Yicong ZhouAbstract:Medical image enhancement is an effective tool to improve visual quality of digital medical images. In this paper, we propose a new Unsharp Masking scheme for medical image enhancement. It embeds the PLIP multiplication into the Unsharp Masking framework. Experimental results demonstrate that the proposed method can effectively enhance the overall contrast and edges of medical images while suppressing background noise.
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parametric rational Unsharp Masking for image enhancement
Proceedings of SPIE, 2014Co-Authors: Changzhe Yin, Yicong Zhou, Sos S Agaian, C Philip L ChenAbstract:Unsharp Masking is an effective enhancement tool to improve the visual quality of fine details in images. However, it also amplifies noisy and over-enhances steep edges. To address this problem, this paper proposes a parametric rational Unsharp Masking. It utilizes the horizontal and vertical gain factors to enhance image details in two directions independently. Experiments and comparisons are provided to demonstrate its excellent enhancement performance.
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Image Processing: Algorithms and Systems - Parametric rational Unsharp Masking for image enhancement
Image Processing: Algorithms and Systems XII, 2014Co-Authors: Changzhe Yin, Yicong Zhou, Sos S Agaian, C. L. Philip ChenAbstract:Unsharp Masking is an effective enhancement tool to improve the visual quality of fine details in images. However, it also amplifies noisy and over-enhances steep edges. To address this problem, this paper proposes a parametric rational Unsharp Masking. It utilizes the horizontal and vertical gain factors to enhance image details in two directions independently. Experiments and comparisons are provided to demonstrate its excellent enhancement performance.
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Nonlinear Unsharp Masking for Mammogram Enhancement
IEEE Transactions on Information Technology in Biomedicine, 2011Co-Authors: Karen Panetta, Yicong Zhou, Sos S Agaian, Hongwei JiaAbstract:This paper introduces a new Unsharp Masking (UM) scheme, called nonlinear UM (NLUM), for mammogram enhancement. The NLUM offers users the flexibility 1) to embed different types of filters into the nonlinear filtering operator; 2) to choose different linear or nonlinear operations for the fusion processes that combines the enhanced filtered portion of the mammogram with the original mammogram; and 3) to allow the NLUM parameter selection to be performed manually or by using a quantitative enhancement measure to obtain the optimal enhancement parameters. We also introduce a new enhancement measure approach, called the second-derivative-like measure of enhancement, which is shown to have better performance than other measures in evaluating the visual quality of image enhancement. The comparison and evaluation of enhancement performance demonstrate that the NLUM can improve the disease diagnosis by enhancing the fine details in mammograms with no a priori knowledge of the image contents. The human-visual-system-based image decomposition is used for analysis and visualization of mammogram enhancement.
Faouzi Alaya Cheikh - One of the best experts on this subject based on the ideXlab platform.
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Unsharp Masking based approach for color image processing
European Signal Processing Conference, 1998Co-Authors: Faouzi Alaya Cheikh, Lazhar Khriji, Moncef GabboujAbstract:In this paper, we present an Unsharp Masking-based approach for noise smoothing and edge enhancing. And apply it to color image processing. The proposed structure is similar to the conventional Unsharp Masking structure, however, a nonlinear function is added to control the behavior of the operator. The proposed scheme enhances the true details, limits the overshoot near sharp edges and attenuates the noise in flat areas. Moreover the use of the control function eliminates the need for the subjective coefficient λ used in the conventional Unsharp Masking technique. Simulations show that the processed image presents sharp edges which makes it more pleasant to the human eye. Moreover, the amount of noise in the image is clearly reduced.
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EUSIPCO - Unsharp Masking-based approach for color image processing
1998Co-Authors: Faouzi Alaya Cheikh, Lazhar Khriji, Moncef GabboujAbstract:In this paper, we present an Unsharp Masking-based approach for noise smoothing and edge enhancing. And apply it to color image processing. The proposed structure is similar to the conventional Unsharp Masking structure, however, a nonlinear function is added to control the behavior of the operator. The proposed scheme enhances the true details, limits the overshoot near sharp edges and attenuates the noise in flat areas. Moreover the use of the control function eliminates the need for the subjective coefficient λ used in the conventional Unsharp Masking technique. Simulations show that the processed image presents sharp edges which makes it more pleasant to the human eye. Moreover, the amount of noise in the image is clearly reduced.
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directional Unsharp Masking based approach for color image enhancement
NMBIA, 1998Co-Authors: Faouzi Alaya Cheikh, Moncef GabboujAbstract:In this paper, we present an Unsharp Masking-based approach for noise smoothing and edge enhancing in multichannel images. The proposed structure is similar to the conventional Unsharp Masking structure, however, the enhancement is allowed only in the direction of maximal change and the enhancement parameter is computed as a nonlinear function of the rate of change. The proposed scheme enhances the true details, limits the overshoot near sharp edges and attenuates noise in flat areas. Moreover the use of the control function eliminates the need for the subjective coefficient λ used in the conventional Unsharp Masking technique.
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NMBIA - Directional Unsharp Masking-Based Approach for Color Image Enhancement
Noblesse Workshop on Non-Linear Model Based Image Analysis, 1998Co-Authors: Faouzi Alaya Cheikh, Moncef GabboujAbstract:In this paper, we present an Unsharp Masking-based approach for noise smoothing and edge enhancing in multichannel images. The proposed structure is similar to the conventional Unsharp Masking structure, however, the enhancement is allowed only in the direction of maximal change and the enhancement parameter is computed as a nonlinear function of the rate of change. The proposed scheme enhances the true details, limits the overshoot near sharp edges and attenuates noise in flat areas. Moreover the use of the control function eliminates the need for the subjective coefficient λ used in the conventional Unsharp Masking technique.
