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Fast code enhancement with local search for fractal image compression

R. Hamzaoui, D. Saupe, M. Hiller
2000 Proceedings 2000 International Conference on Image Processing (Cat. No.00CH37101)  
Optimal fractal coding consists of finding in a finite set of contractive affine mappings one whose unique fixed point is closest to the original image.  ...  In a previous study, we proposed a local search algorithm that significantly improves on collage coding.  ...  In fractal image compression, the code is a representation of a contractive affine mapping in a complete metric space of digital images [5] .  ... 
doi:10.1109/icip.2000.899251 dblp:conf/icip/HamzaouiSH00 fatcat:3gtn645tjngn5mvbb6luyb6bw4

SDALA: Simultaneous dynamic range compression and local contrast enhancement algorithm

Chi-Yi Tsai
2011 2011 18th IEEE International Conference on Image Processing  
Index Terms-Low dynamic range image enhancement, dynamic range compression, local contrast enhancement  ...  This paper presents a novel simultaneous dynamic range compression and local contrast enhancement algorithm, termed as SDALA, to resolve low dynamic range (LDR) image enhancement problem.  ...  range compression with local contrast preservation/enhancement for LDR images.  ... 
doi:10.1109/icip.2011.6115681 dblp:conf/icip/Tsai11 fatcat:pbdpitb3rjfw7k47kdtjpuvili

A fast dynamic range compression with local contrast preservation algorithm for low dynamic range image enhancement

Chi-Yi Tsai
2012 2012 IEEE International Conference on Signal Processing, Communication and Computing (ICSPCC 2012)  
Index Terms-Low dynamic range image enhancement, color image enhancement, dynamic range compression, local contrast preservation 978-1-4673-2193-8/12/$31.00 ©2012 IEEE  ...  In combination with the FDRCLCP algorithm, a new intensity-transfer function that achieves satisfactory dynamic-range compression while preventing over enhancement in dark regions of the image is proposed  ...  The former compresses dynamic range of the input image, and the latter restores local contrast after range compression.  ... 
doi:10.1109/icspcc.2012.6335585 fatcat:ceiogzizyfanffp3nuy5hiftze

Image enhancement using a contrast measure in the compressed domain

Jinshan Tang, E. Peli, S. Acton
2003 IEEE Signal Processing Letters  
The advantages of the psychophysically motivated algorithm are 1) the algorithm does not affect the compressibility of the original image because it enhances the images in the decompression stage and 2  ...  Index Terms-Compressed domain, contrast measure, discrete cosine transform (DCT), human vision system, image enhancement, JPEG/MPEG.  ...  Image Enhancement in JPEG Domain There are three ways to enhance the JPEG compressed images. The first is to enhance the image before compression.  ... 
doi:10.1109/lsp.2003.817178 fatcat:oaje5trmazfufdmtfodqcu7hse

Image enhancement for improving face detection under non-uniform lighting conditions

Numan Unaldi, Praveen Sankaran, Vijayan K. Asari, Zia-ur Rahman
2008 2008 15th IEEE International Conference on Image Processing  
Index Terms-Image Enhancement, dynamic range compression, local contrast enhancement, face detection.  ...  A new wavelet-based image enhancement algorithm is proposed to improve performance of face detection in non-uniform lighting environment with high dynamic range.  ...  compression preserving the local contrast and tonal rendition has been developed to improve the visual quality of the digital images.  ... 
doi:10.1109/icip.2008.4712009 dblp:conf/icip/UnaldiSAR08 fatcat:moi7vgt3vndypljrvfyykha7aa

Learning-Based Image Restoration for Compressed Image through Neighboring Embedding [chapter]

Lin Ma, Feng Wu, Debin Zhao, Wen Gao, Siwei Ma
2008 Lecture Notes in Computer Science  
Furthermore, with the assumption that small image patches in the enhanced and real high frequency images form manifolds with similar local geometry in the corresponding image feature spaces, a neighboring  ...  a training set of natural images.  ...  In the Enhancing step, local consistency of enhanced differential image E I is preserved by blending the predictive HF image P I into D I .  ... 
doi:10.1007/978-3-540-89796-5_29 fatcat:kier4y2s7vhv5bh7mabaqbh3ru

Fast and robust wavelet-based dynamic range compression with local contrast enhancement

Numan Unaldi, Vijayan K. Asari, Zia-ur Rahman, Zia-ur Rahman, Stephen E. Reichenbach, Mark A. Neifeld
2008 Visual Information Processing XVII  
Wavelet transform is used especially for dimension reduction such that a dynamic range compression with local contrast enhancement algorithm is applied only to the approximation coefficients which are  ...  A color restoration process based on relationship between spectral bands and the luminance of the original image is applied to convert the enhanced intensity image back to a color image.  ...  Fig. 2 . 2 Raised hyperbolic sine function ' 4 Fig. 3 . 43 Results of the proposed algorithm at each step Top, left: Original image; right: Range compressed image; bottom left: Local contrast enhanced  ... 
doi:10.1117/12.778025 dblp:conf/spieVIP/UnaldiAR08 fatcat:lqet3ujsynh2jex4wxnijxaaee

Real-time content adaptive contrast enhancement for see-through fog and rain

Zhen Jia, Hongcheng Wang, Rodrigo Caballero, Ziyou Xiong, Jianwei Zhao, Alan Finn
2010 2010 IEEE International Conference on Acoustics, Speech and Signal Processing  
The proposed algorithm adaptively enhances the global and local contrast of a surveillance video.  ...  The algorithm is inspired on the human visual system, and accounts for the perceptual sensitivity to noise, compression artifacts, and the texture of image content.  ...  enhancement for each region of the image is determined by local image statistics.  ... 
doi:10.1109/icassp.2010.5495454 dblp:conf/icassp/JiaWCXZF10 fatcat:mzezllx7cvhstdjjjzgm4boghe

Nonlinear Image Enhancement to Improve Face Detection in Complex Lighting Environment

Vijayan K. Asari, Ming-Jung Seow, Li Tao
2006 International Journal of Computational Intelligence Research  
A neighborhood dependent local contrast enhancement method is used to enhance the images contrast following the dynamic range compression.  ...  The proposed technique processes images in two separate steps: dynamic range compression and local contrast enhancement.  ...  In order to improve the visual quality of images produced by the dynamic range compression, a contrast enhancement method is used to enhance the local contrast of these images.  ... 
doi:10.5019/j.ijcir.2006.70 fatcat:u43gvc42evc3li2ebzynjawagu

Nonlinear image enhancement to improve face detection in complex lighting environment

Li Tao, Ming-Jung Seow, Vijayan K. Asari, Edward R. Dougherty, Jaakko T. Astola, Karen O. Egiazarian, Nasser M. Nasrabadi, Syed A. Rizvi
2006 Image Processing: Algorithms and Systems, Neural Networks, and Machine Learning  
A neighborhood dependent local contrast enhancement method is used to enhance the images contrast following the dynamic range compression.  ...  The proposed technique processes images in two separate steps: dynamic range compression and local contrast enhancement.  ...  In order to improve the visual quality of images produced by the dynamic range compression, a contrast enhancement method is used to enhance the local contrast of these images.  ... 
doi:10.1117/12.643262 fatcat:6h7pvuopfzdihcw6bvv7gczffi

Nonlinear Transfer Function-Based Image Detail Preserving Dynamic Range Compression for Color Image Enhancement [chapter]

Deepak Ghimire, Joonwhoan Lee
2011 Lecture Notes in Computer Science  
By applying image dependent nonlinear transfer function the local image contrast preserving dynamic range compression as well as contrast enhancement is performed simultaneously on the V channel image.  ...  Finally, the enhanced V channel image and original H and S channel images are converted back to RGB image to obtain enhanced RGB image.  ...  [12] for dynamic range compression with preserving local image contrast. This algorithm automatically and adaptively enhances the local image contrast in the highlighted regions.  ... 
doi:10.1007/978-3-642-25367-6_1 fatcat:7bznsduoafb4bpx467c5llxany

Observer Evaluations of Wavelet Methods for the Enhancement and Compression of Digitized Mammograms [chapter]

Maria Kallergi, John J. Heine, Bradley J. Lucier
2006 Lecture Notes in Computer Science  
Two observer experiments were performed to evaluate the performance of wavelet enhancement and compression methodologies for digitized mammography.  ...  An important outcome of this work was that lossy wavelet compression was as successful in improving the quality of digitized mammograms as the wavelet enhancement technique.  ...  Applications range from image compression to image enhancement, feature extraction and segmentation to image reconstruction.  ... 
doi:10.1007/11783237_65 fatcat:ze2cev65dfbevjda2adz7w54my

Bas-Relief Modeling with Detail Preservation and Local Significance Enhancement

Zhongping Ji, Qiankan Zhang, Mingqiang Wei
2020 IEEE Access  
More than that, the watershed algorithm is used to segment the height map of bas-relief, and local detail enhancement or local depth constraint is implemented through mask operation to improve the local  ...  each region of the input image to receive the same level of smoothing.  ...  Then, the significance of local features can be enhanced by local detail enhancement or local depth constraint of the bas-relief. II.  ... 
doi:10.1109/access.2020.2977228 fatcat:ymf4sdvbe5eavnqhsvpik22tda

A novel simultaneous dynamic range compression and local contrast enhancement algorithm for digital video cameras

Chi-Yi Tsai, Chien-Hsing Chou
2011 EURASIP Journal on Image and Video Processing  
Keywords: low dynamic range image enhancement, dynamic range compression, local contrast enhancement, statistics of visual representation, quantitative evaluation.  ...  Experimental results show that the performance of the proposed method outperforms three state-of-the-art methods in terms of dynamic range compression and local contrast enhancement.  ...  Acknowledgements This study was supported by the National Science Council of Taiwan, ROC, under the grant nos. NSC 99-2218-E-032-004 and NSC 100-2221-E-032-011.  ... 
doi:10.1186/1687-5281-2011-6 fatcat:ebrs3kg7cje5jhb2onc6wjkgpu

An Automatic Wavelet based non-linear Image Enhancement for both Grayscale & Color Images

Prof. Arjun Nichal, Ms.Vasudha Patil, Ms.Nehali Pawar, Ms.Ashwini Shinde
2015 IJIREEICE  
The fast image enhancement algorithm which provides dynamic range compression preserving the local contrast and tonal rendition is a very good candidate in aerial imagery applications such as image interpretation  ...  In this paper the latest version of the proposed algorithm which is able to enhance images so that the enhanced images are better than direct human observation, is presented.  ...  The compressed coefficients at level J can be obtained by Local Contrast Enhancement The local contrast enhancement which employs a center/surround approach is carried out as follows: The surrounding  ... 
doi:10.17148/ijireeice.2015.3405 fatcat:gz277p3apbds3hvzgvl4dt6jyi
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