• Title/Summary/Keyword: Image Edge

Search Result 2,465, Processing Time 0.028 seconds

Observer Preferable Sharpness Enhancement Considering Distributions of Edge Characteristics (경계선 특성을 고려한 관측자 선호 선예도 개선 방법)

  • 홍상기;정재영;김대희;조맹섭
    • Proceedings of the IEEK Conference
    • /
    • 2002.06d
    • /
    • pp.275-278
    • /
    • 2002
  • Sharpness enhancement, which strengthen the edge(high frequency) of image, is widely studied for image processing research area. In this paper, psychophysical experiment is conducted by the 20 observers with simple linear unsharp masking for sharpness enhancement. The experimental results extracted using z-score analysis and linear regression suggests observer preferable sharpness enhancement method for digital television.

  • PDF

A Depth Estimation Using Infocused and Defocused Images (인포커스 및 디포커스 영상으로부터 깊이맵 생성)

  • Mahmoudpour, Seed;Kim, Manbae
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2013.11a
    • /
    • pp.114-115
    • /
    • 2013
  • The blur amount of an image changes proportional to scene depth. Depth from Defocus (DFD) is an approach in which a depth map can be obtained using blur amount calculation. In this paper, a novel DFD method is proposed in which depth is measured using an infocused and a defocused image. Subbaro's algorithm is used as a preliminary depth estimation method and edge blur estimation is provided to overcome drawbacks in edge.

  • PDF

Application of An Adaptive Self Organizing Feature Map to X-Ray Image Segmentation

  • Kim, Byung-Man;Cho, Hyung-Suck
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2003.10a
    • /
    • pp.1315-1318
    • /
    • 2003
  • In this paper, a neural network based approach using a self-organizing feature map is proposed for the segmentation of X ray images. A number of algorithms based on such approaches as histogram analysis, region growing, edge detection and pixel classification have been proposed for segmentation of general images. However, few approaches have been applied to X ray image segmentation because of blur of the X ray image and vagueness of its edge, which are inherent properties of X ray images. To this end, we develop a new model based on the neural network to detect objects in a given X ray image. The new model utilizes Mumford-Shah functional incorporating with a modified adaptive SOFM. Although Mumford-Shah model is an active contour model not based on the gradient of the image for finding edges in image, it has some limitation to accurately represent object images. To avoid this criticism, we utilize an adaptive self organizing feature map developed earlier by the authors.[1] It's learning rule is derived from Mumford-Shah energy function and the boundary of blurred and vague X ray image. The evolution of the neural network is shown to well segment and represent. To demonstrate the performance of the proposed method, segmentation of an industrial part is solved and the experimental results are discussed in detail.

  • PDF

Invader Detection System Using the Morphological Filtering and Difference Images Based on the Max-Valued Edge Detection Algorithm

  • Lee, Jae-Hyun;Kim, Sung-Shin;Kim, Jung-Min
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.36 no.5
    • /
    • pp.645-661
    • /
    • 2012
  • Recently, pirates are infesting on the sea and they have been hijacking the several vessels for example Samho Dream and Samho Jewelry of Korea. One of the items to reduce the risk is to adopt the invader detection system. If the pirates break in to the ship, the detection system can monitor the pirates and then call the security alarm. The crew can gain time to hide to the safe room and the report can be automatically sent to the control room to cope with the situation. For the invader detection, an unmanned observation system was proposed using the image detection algorithm that extracts the invader image from the recording image. To detect the motion area, the difference value was calculated between the current image and the prior image of the invader, and the 'AND' operator was used in calculated image and edge line. The image noise was reduced based on the morphology operation and then the image was transformed into morphological information. Finally, a neural network model was applied to recognize the invader. In the experimental results, it was confirmed that the proposed approach can improve the performance of the recognition in the invader monitoring system.

Design and Performance Analysis of Adaptive Pseudomedian Filter for Digital Image Enlargement (디지털 영상 확대를 위한 적응형 Pseudomedian 필터의 설계 및 성능 분석)

  • Gwak, No-Yun;Hwang, Byeong-Won
    • The Transactions of the Korea Information Processing Society
    • /
    • v.7 no.4
    • /
    • pp.1305-1315
    • /
    • 2000
  • It is known that a digital image enlargement technique can increase the size of he image but the practical enhancement of resolution is trifle because the frequency bandwidth of the original image is basically limited. To solve this problem, this paper proposes the digital image enlargement technique which interpolates the interpolation points of horizontal and vertical direction by weighting according to the direction of edge information with the component of FOI(First Order Interpolation)and output of the pseudomedian filter for image enlargement and interpolates the interpolation points of diagonal direction by selectively transposing the direction of the subwindows of the pseudomedian filter according to the distribution of neighbored pixels thereto in the extended image. According to the proposed methods, the digital image enlargement which preserves the characteristic of the pseudomedian filter capable of keeping the reconstruction of edge information and reflects the advantage of FOI can be performed. Therefore, visual artifacts could be effectively suppressed, and most characteristics and shape of the original image can be reconstructed as well.

  • PDF

Expert system for segmentation of 2.5-D image

  • Ahn, Hongyoung
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1992.10b
    • /
    • pp.376-381
    • /
    • 1992
  • This paper presents an expert system for the segmentation of a 2.5-D image. The results of two segmentation approaches, edge-based and region-based, are combined to produce a consistent and reliable segmentation. Rich information embedded in the 2.5-D image is utilized to obtain a view independent surface patch description of the image, which can facilitate object recognition considerably.

  • PDF

A Study on the Edge Detection using Modified Expansion Mask (변형된 확장 마스크를 이용한 에지 검출에 관한 연구)

  • Lee, Chang-Young;Hwang, Yeong-Yeun;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2012.05a
    • /
    • pp.630-632
    • /
    • 2012
  • Contemporary society has evolved in the digital information age. Because of this, use of various digital images has been increased. To process these images, various digital image processing methods are used. Edge detection methods, one of those, are utilized to various areas of application such as object recognition, line detection. To detect edge, there are many methods such as Sobel, Prewitt, Laplacian. Because images which are dealt with existing methods are processed in same methods regardless the distribution of gray-level in image, edge detection property is insufficient. Therefore, In this study, to improve shortcomings of existing methods an algorithm using modified expansion mask is proposed.

  • PDF

Image Compression with Edge Directions based on DCT-VQ (DCT-VQ를 기반으로 한 에지의 방향성을 갖는 영상압축)

  • 김진태;김동욱;임한규
    • Journal of Korea Multimedia Society
    • /
    • v.1 no.2
    • /
    • pp.194-203
    • /
    • 1998
  • In this paper, a new DCT-VQ method is proposed which can solve the problems of VQ such as the degradation of edge and enormous calculations. VQ is carried in DCT domain but spatial domain in order to protect the degradation of edge. DCT makes high correlated image data decorrelated and the energy concentrated on a few coefficients. In DCT domain, the DC coefficient is quantized with 8 bits uniform scalar quantizer and the AC coefficients are divided to three regions and coded with vector qiantizer for considering edge components. For the decrease of the calculation and memory, the vectors for three region have small dimension of $1{\times}7$ and use the same codebook. Thus, the proposed method can fully express the edge components by considering AC coefficients in DCT domain and decrease the calculation and memory be reducing the dimension of vectors.

  • PDF

Extraction of Car Number Plate Based on Edge Projection (에지투영 기반의 자동차 번호판 영역 추출)

  • Kim, Dong-Wook;Kang, Jeong-Hyuck
    • Journal of the Korea Society of Computer and Information
    • /
    • v.12 no.6
    • /
    • pp.261-268
    • /
    • 2007
  • In this paper, We propose a new technique extract efficiently a car number plate based on edge projection. In order to obtain the region of car number plate, we use a motive that the luminance differences between the number plate background and characters. And, we introduce a projection technique to obtain character parts based on edge image. In vertical direction. we propose a shape matching method. Specially the new number plate standard has more characters than the old one in horizontal direction and, it is efficiently used to extract the number plate. Therefore, the proposed technique is useful to the new number plate standard. In simulation results. We have illustrated that our algorithm can recognize different number plates with a success ration of 90%.

  • PDF