Dr. Sang Ho Kim Profile

Dr. Sang Ho Kim

at Samsung Electronics Co Ltd

SPIE Involvement:

Author

Publications (24)

Proceedings Article | 8 February 2015 Paper

Fast Algorithm for Visibility Enhancement of the Images with Low Local Contrast

Ilya Kurilin, Ilia Safonov, Michael Rychagov, Sergey Zavalishin, Dong Hyeop Han, Sang Ho Kim

Proceedings Volume 9395, 93950B (2015) https://doi.org/10.1117/12.2078975

KEYWORDS: Visibility, Image enhancement, RGB color model, Visualization, Image filtering, Image processing, Linear filtering, Optimization (mathematics), Image contrast enhancement, High dynamic range imaging

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Proceedings Article | 3 February 2014 Paper

High-performance automatic cropping and deskew of multiple objects on scanned images

Ilya Kurilin, Ilia Safonov, Michael Rychagov, Hokeun Lee, Sang Ho Kim

Proceedings Volume 9016, 90160B (2014) https://doi.org/10.1117/12.2037257

KEYWORDS: Image segmentation, Image processing algorithms and systems, Scanners, Image resolution, Image processing, Binary data, Detection and tracking algorithms, Image classification, Image quality, Algorithm development

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Proceedings Article | 4 February 2013 Paper

Generation of PDF with vector symbols from scanned document

Ilya Kurilin, Ilia Safonov, Michael Rychagov, Hokeun Lee, Sang Ho Kim, Donchul Choi

Proceedings Volume 8653, 86530R (2013) https://doi.org/10.1117/12.2000527

KEYWORDS: Raster graphics, Image segmentation, Resolution enhancement technologies, Visualization, Evolutionary algorithms, Corner detection, Image resolution, Electronics, Optical character recognition, Printing

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Proceedings Article | 25 January 2012 Paper

Bio-inspired color sketch for eco-friendly printing

Ilia Safonov, Ekaterina Tolstaya, Michael Rychagov, Hokeun Lee, Sang Ho Kim, Donchul Choi

Proceedings Volume 8292, 829218 (2012) https://doi.org/10.1117/12.906736

KEYWORDS: Printing, Biomimetics, Edge detection, Image enhancement, Visual process modeling, Human vision and color perception, Detection and tracking algorithms, Raster graphics, Image processing, Color printing

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Proceedings Article | 25 January 2011 Paper

Fast approach for toner saving

Ilia Safonov, Ilya Kurilin, Michael Rychagov, Hokeun Lee, Sangho Kim, Donchul Choi

Proceedings Volume 7866, 786618 (2011) https://doi.org/10.1117/12.872123

KEYWORDS: Raster graphics, Printing, Optical character recognition, Solids, Visualization, Absorbance, 3D printing, Patents, Image quality, Electronics

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Proceedings Article | 25 January 2011 Paper

A restoration method for distorted image scanned from a bound book

HyungSoo Ohk, HyunSeok Seo, KiMin Kang, Sangho Kim, DonChul Choi

Proceedings Volume 7866, 78661T (2011) https://doi.org/10.1117/12.876758

KEYWORDS: Distortion, Scanners, Glasses, Image sensors, Spine, Charge-coupled devices, Sensors, Feature extraction, Image processing, Image analysis

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Proceedings Article | 27 January 2010 Paper

Adaptive removal of show-through artifacts by histogram analysis

Jin-Kyung Hong, Ki-Min Kang, Sang-Ho Kim

Proceedings Volume 7533, 75330N (2010) https://doi.org/10.1117/12.838723

KEYWORDS: Image processing, Scanners, Analytical research, Detection and tracking algorithms, Image analysis, Algorithm development, Digital electronics, Printing, Electronics, Digital image processing

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Proceedings Article | 19 January 2010 Paper

Descreening of scanned images

Ilya Kurilin, Ilia Safonov, HoKeun Lee, Sang Ho Kim

Proceedings Volume 7528, 75280D (2010) https://doi.org/10.1117/12.838444

KEYWORDS: Halftones, Image filtering, Image processing, RGB color model, Linear filtering, Visualization, Optical filters, High dynamic range imaging, Detection and tracking algorithms, Printing

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Screen or halftone pattern appears on the majority of images printed on electrophotographic and ink-jet printers as well as offset machines. When such halftoned image is scanned, a noisy effect called a Moiré pattern often appears on the image. There are plenty of methods proposed for descreening of images. Common way is adaptive smoothing of scanned images. However the descreening techniques face the following dilemma: deep screen reduction and restoration of contone images leads to blurring of sharp edges of text and other graphics primitives, on the other hand insufficient smoothing keeps screen in halftoned areas. We propose novel descreening algorithm that is primarily intended for preservation of sharpness and contrast of text edges and for restoration contone images from halftone ones accurately. Proposed technique for descreening of scanned images comprises five steps. The first step is decrease of edge transition slope length via local tone mapping with ordering; it is carried out before adaptive smoothing, and it allows better preservation of edges. Adaptive low-pass filter applies simplified idea of Non-Local Means filter for area classification; similarity is calculated between central block of window and different adjacent block that is selected randomly. If similarity is high then current pixel relates to flat region, otherwise pixel relates to edge region. For prevention of edges blurring, flat regions are smoothed stronger than edge regions. By random selection of blocks we avoid the computational overhead related to excessive directional edge detection. Final three stages include additional decrease of edge transition slope length using local tone mapping, increase of local contrast via modified unsharp mask filter, that uses bilateral filter with special edge-stop function for modest smoothing of edges, and global contrast stretching. These stages are intended to compensate decreasing of sharpness and contrast due to low-pass filtering, it allows to enhance visual quality of scanned image. For parameters adjusting for different scanning resolutions and comparison with existing techniques test target and criteria were proposed. Also the quality of proposed approach is evaluated by surveying observer's opinions. According to obtained outcomes the proposed algorithm demonstrates good descreening capabilities.

Proceedings Article | 19 January 2010 Paper

Removal of blocking and ringing artifacts in JPEG-coded images

Ekaterina Tolstaya, Michael Rychagov, Sang Kim, Don Choi

Proceedings Volume 7537, 75370O (2010) https://doi.org/10.1117/12.838447

KEYWORDS: Image processing, Image filtering, Image compression, Image quality, Quantization, Image enhancement, Edge detection, Digital filtering, Cameras, Algorithms

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Proceedings Article | 18 January 2010 Paper

Development of ISO/IEC 29112: test charts and methods for measuring monochrome printer resolution

Eric Zeise, Sang Ho Kim, Franz Sigg

Proceedings Volume 7529, 75290F (2010) https://doi.org/10.1117/12.845965

KEYWORDS: Printing, Modulation transfer functions, Scanners, Spatial frequencies, Visualization, Modulation, Standards development, Reflectivity, Imaging systems, Image resolution

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Proceedings Article | 19 January 2009 Paper

Measurement of contributing attributes of perceived printer resolution.

Eric Zeise, Sang Ho Kim, Brian Cooper, Franz Sigg

Proceedings Volume 7242, 724205 (2009) https://doi.org/10.1117/12.806882

KEYWORDS: Modulation transfer functions, Printing, Spatial frequencies, Scanners, Stochastic processes, Imaging systems, Modulation, Standards development, Resolution enhancement technologies, Image resolution

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Proceedings Article | 19 January 2009 Paper

Fusion of high dynamic range scene photos

Ekaterina Tolstaya, Michael Rychagov, KiMin Kang, Sang Ho Kim

Proceedings Volume 7250, 72500Y (2009) https://doi.org/10.1117/12.811530

KEYWORDS: High dynamic range imaging, Image fusion, Cameras, Image processing, Image compression, Image filtering, Sensors, Signal attenuation, Photography, Printing

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Proceedings Article | 19 January 2009 Paper

Retargeting of digital photos and documents

V. Bucha, I Safonov, M. Rychagov, J.K. Hong, S.H. Kim

Proceedings Volume 7250, 72500Z (2009) https://doi.org/10.1117/12.811832

KEYWORDS: Image processing, Video, Printing, Digital photography, Computer programming, Image segmentation, Skin, Sensors, Video acceleration, Video compression

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Proceedings Article | 28 January 2008 Paper

Adaptive sharpening of photos

Ilia Safonov, Michael Rychagov, KiMin Kang, Sang Ho Kim

Proceedings Volume 6807, 68070U (2008) https://doi.org/10.1117/12.758613

KEYWORDS: Image filtering, Printing, Linear filtering, Molybdenum, Edge detection, Decision support systems, Convolution, Photography, Gaussian filters, Image processing

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Proceedings Article | 28 January 2008 Paper

Printer resolution measurement based on slanted edge method

Yousun Bang, Sang Ho Kim, Don Chul Choi

Proceedings Volume 6808, 680807 (2008) https://doi.org/10.1117/12.764776

KEYWORDS: Printing, Scanners, Spatial frequencies, Visualization, Optical resolution, Halftones, Nonimpact printing, Resolution enhancement technologies, Image resolution, Cameras

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Proceedings Article | 28 January 2008 Paper

Automatic red eye correction and its quality metric

Ilia Safonov, Michael Rychagov, KiMin Kang, Sang Ho Kim

Proceedings Volume 6807, 68070W (2008) https://doi.org/10.1117/12.758603

KEYWORDS: Eye, Skin, Image segmentation, Image filtering, Edge detection, Chromium, Printing, 3D image processing, Image processing, Machine learning

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Proceedings Article | 29 January 2007 Paper

A novel color mapping method for preferred color reproduction

Kyeong Man Kim, Hyun Soo Oh, Sang Ho Kim, Don Chul Choi

Proceedings Volume 6493, 64930J (2007) https://doi.org/10.1117/12.705501

KEYWORDS: Printing, RGB color model, Calibration, 3D acquisition, CMYK color model, 3D printing, Detection and tracking algorithms, Color reproduction, Visualization, Inkjet technology

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Proceedings Article | 29 January 2007 Paper

Resolution enhancement techniques for halftoned images

Byong Tae Ryu, Jong Ok Lee, Choon-Woo Kim, Ho Keun Lee, Sang Ho Kim

Proceedings Volume 6493, 64931C (2007) https://doi.org/10.1117/12.705494

KEYWORDS: Binary data, Printing, Resolution enhancement technologies, Spatial resolution, Halftones, Genetic algorithms, Image resolution, Image processing, Image quality, Computer programming

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Proceedings Article | 16 January 2006 Paper

AM-FM hybrid color screen design to reduce brightness variation

Byong Min Kang, Byong Tae Ryu, Choon-Woo Kim, Sang Ho Kim

Proceedings Volume 6058, 60580T (2006) https://doi.org/10.1117/12.643690

KEYWORDS: Printing, Distance measurement, Halftones, Fermium, Frequency modulation, Optical filters, Amplitude modulation, Diffusion, Gaussian filters, Convolution

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Proceedings Article | 16 January 2006 Paper

Model-based clustered-dot screening

Sang Ho Kim

Proceedings Volume 6058, 60580S (2006) https://doi.org/10.1117/12.642829

KEYWORDS: Model-based design, Halftones, Printing, Binary data, Visual system, Visual process modeling, Visualization, Image processing, Digital image processing, Diffusion

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SPIE Journal Paper | 1 April 2005

Optimal unsharp mask for image sharpening and noise removal

Sang Ho Kim, Jan Allebach

JEI, Vol. 14, Issue 02, 023005, (April 2005) https://doi.org/10.1117/12.10.1117/1.1924510

KEYWORDS: Linear filtering, Photography, Modulation transfer functions, Image restoration, Scanners, Cameras, Image filtering, Digital imaging, Image processing, Point spread functions

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Proceedings Article | 21 May 2004 Paper

Optimal unsharp mask for image sharpening and noise removal

Sang Ho Kim, Jan Allebach

Proceedings Volume 5299, (2004) https://doi.org/10.1117/12.538366

KEYWORDS: Image filtering, Digital filtering, Photography, Nonlinear filtering, Cameras, Linear filtering, Imaging systems, Modulation transfer functions, Analog electronics, Image processing

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Proceedings Article | 21 December 2000 Paper

Impact of HVS models on model-based halftoning

Sang Ho Kim, Jan Allebach

Proceedings Volume 4300, (2000) https://doi.org/10.1117/12.410817

KEYWORDS: Halftones, Visual process modeling, Printing, Model-based design, Point spread functions, Convolution, Visual system, Algorithm development, Performance modeling, Contrast sensitivity

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