• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.9
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• pp.76-83
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• 1993

A morphological filtering algorithm using directional information is presented. Directional filtering technique is effective in reducing noises and preserving edges. The proposed directional filtering is composed of two stage filtering processes. The opening and closing operations in the lst stage are performed for the pixels is aligned to the vertical, horizontal, and two diagonal directions, respectively. The opening operation supresses the positive impulse noises, while the closing operation the negative ones. Then, each directional result and their average value are filtered by the opening or closing operations in the 2nd stage. The averaging operation diminishes the effects of Gaussian noises in the homogeneous regions. Thus, the morphological operation in the 1 st stageremoves the impulse noises and in 2nd stage reduces. Gaussian ones. The experimental results show that the proposed filtering is superior to the existing nonlinear filtering in the aspects of the subjective quality. Also, the morphological filtering method reduces the computational loads.

• KIEE International Transaction on Systems and Control
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• v.2D no.2
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• pp.115-119
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• 2002

In this paper we present a generalized directional morphological filtering algorithm for the removal of impulse noise, which is based on a combination of impulse noise detection and a weighted rank-order morphological filtering technique. For salt (or pepper) noise suppression, the generalized directional opening (or closing) filtering of the input signal is selectively used. The detection of impulse noise can be done by the geometrical difference of opening and closing filtering. Simulations show that this new filter has better detail feature preservation with effective noise reduction compared to other nonlinear filtering techniques.

• Journal of information and communication convergence engineering
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• v.7 no.4
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• pp.535-538
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• 2009

Speckle noise reduction for ultrasound CT image using morphological adaptive median filtering based on edge preservation is presented in this paper. Speckle noise is multiplicative feature and causes ultrasound image to degrade widely from transducer. An input image is classified into edge region and homogeneous region in preprocessing. The speckle is reduced by morphological operation on the 2D gray scale by using convolution and correlation, and edges are preserved. The adaptive median is processed to reduce an impulse noise to preserve edges. As the result, MAM of the proposed method enhances the image to about 10% in comparison with Winner filter by Edge Preservation Index and PSNR, and 10% to only adaptive median filtering.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.329-332
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• 2009

Speckle noise reduction for ultrasound CT image using morphological adaptive median filtering based on edge preservation is presented in this paper. Speckle noise is multiplicative feature and causes ultrasound image to degrade widely from transducer. An input image is classified into edge region and homogeneous region in preprocessing. The speckle is reduced by morphological operation on the 2D gray scale by using convolution and correlation, and edges are preserved. The adaptive median is processed to reduce an impulse noise. As the result the proposed method enhances the image to about 20% in comparison with Winer filter by Edge Preservation Index and PSNR.

• Proceedings of the KSRS Conference
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• v.2
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• pp.736-739
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• 2006

While hyperspectral data are very rich in information, their processing poses several challenges such as computational requirements, noise removal and relevant information extraction. In this paper, the application of advanced scale-space filtering to selected hyperspectral bands was investigated. In particular, a pre-processing tool, consisting of anisotropic diffusion and morphological leveling filtering, has been developed, aiming to an edge-preserving smoothing and simplification of hyperspectral data, procedures which are of fundamental importance during feature extraction and object detection. Two scale space parameters define the extent of image smoothing (anisotropic diffusion iterations) and image simplification (scale of morphological levelings). Experimental results demonstrated the effectiveness of the developed scale space filtering for the enhancement and smoothing of hyperspectral remote sensing data and their advantage against watershed over-segmentation problems and edge detection.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.9 no.3
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• pp.172-177
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• 2009

In this paper, a new morphology-based homomorphic filtering technique is presented to enhance features in medical images. The homomorphic filtering is performed based on the morphological sub-bands, in which an image is morphologically decomposed. An evolutionary design is carried to find an optimal gain and structuring element of each sub-band. As a search algorithm, Differential Evolution scheme is utilized. Simulations show that the proposed filter improves the contrast of the interest feature in medical images.

• Journal of IKEEE
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• v.18 no.2
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• pp.234-239
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• 2014

This paper proposes a new automatic detection method to inspect mura defects on display film surface using morphological image processing and labeling. This automatic detection method for mura defects on display films comprises 3 phases of preprocessing with morphological image processing, Gabor filtering, and labeling. Since distorted results could be obtained with the presence of non-uniform illumination, preprocessing step reduces illumination components using morphological image processing. In Gabor filtering, mura images are created with binary coded mura components using Gabor filters. Subsequently, labeling is a final phase of finding the mura defect area using the difference between large mura defects and values in the periphery. To evaluate the accuracy of the proposed detection method, detection rate was assessed by applying the method in 200 display film samples. As a result, the detection rate was high at about 95.5%. Moreover, the study was able to acquire reliable results using the Semu index for luminance mura in image quality inspection.

• The KIPS Transactions:PartB
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• v.9B no.6
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• pp.727-734
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• 2002

Currently. people become interested in the development of measuring instrument related to eyesight. In this study, we developed software of electronic part in automatic refracto-keratometer. If an automatic system, which uses images from an optical instrument, can inform the in-spector of an accurate eyesight measured value after the internal process, the frequency of mistakenly observed value will be reduced considerably. This software is using morphological filtering and gray-level signal enhancing techniques. The morphological filtering is the first process, from images of the optical instrument, to transform an original image which is hard to process into manageable one. The second process is a signal enhancing technique to the first processed image using gray -level thresholding technique and is used to reduce an error caused by the variety in distribution of the gray value of image. Therefore, this software system in electronic part will make more effective eyesight measurement by reducing the error effectively when applied to the optical image which is difficult to get accurate measurement value.

• Journal of Korea Game Society
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• v.3 no.1
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• pp.86-93
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• 2003

In this paper, we propose a new antialiasing method using filtering technique which is base on morphological pixel structure Aliasing occurs along the edge of lines and polygons. This undesirable effect happens because there are not enough pixels available on a typical monitor to properly display mathematically smooth lines and polygon edges. Aliasing can be very distracting. In a typical graphic scene, aliasing artifact will be visible along the edges of all objects that greatly diminish of realism. The proposed antialiasing method attempts to smooth extreme jagged contour lines and edges by properly handling pixel's structure, surface type and adjusting the pixel color according to the amount of pixel coverage. Next, we use filtering technique considering morphological pixel structure. Experimental results have shown that the propose algorithm achieves better performance in reducing noise for antialiasing. The method will be widely applied to basic antialiasing technique for computer graphic applications.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.819-822
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• 2005

본 연구는 MDCT 영상을 이용하여 인체의 장기인 간을 추출하고 그 간 내부의 혈관을 추출하는 알고리즘을 제안하였다. 간에는 2개의 주요혈관이 있는데 생체 간 이식 수술시 필수적인 간의 절개 비율 및 간 내의 혈관 모습들을 제공하여 의료진에게 수술 전 혈관 형태에 대한 정확히 정보를 파악하도록 함으로써 혈관의 손상을 최대한으로 줄일 수 있도록 하여 수술 성공률을 높이는데 중요한 역할을 할 수 있다. 간을 이식 할 때 기증자와 수혜자가 동시에 생존하기 위해서는 기증자의 간으 크기가 중요하며 둘다 생존하기 위해서는 기증자는 자신의 간의 35% 이상을 남겨야 하며 수혜자 또한 생존을 위해 자신의 간의 40% 이상에 해당하는 간을 이식 받아야 하는데 간 이식에 있어서 절단 부분을 결정하는데 중요한 중간 정맥을 찾아내어 보여 줌으로써 중간 정맥을 중심으로 3가닥의 굵은 혈관과 주변혈관의 손상을 최소화하고 비율을 잘 맞추어 절단 할 수 있도록 수술하는데 도움을 줄 수 있다. 각 혈관은 원형성과 다양한 각도를 갖는 막대형의 형태를 가지고 있다는 특징을 이용해 morphological filtering을 통해 추출한 후 조합하여 재구성을 하여 혈관의 모습으로 생성해 낼 수 있었다.