• Title/Summary/Keyword: Edge extraction

Search Result 502, Processing Time 0.02 seconds

Refinement of Building Boundary using Airborne LiDAR and Airphoto (항공 LiDAR와 항공사진을 이용한 건물 경계 정교화)

  • Kim, Hyung-Tae;Han, Dong-Yeob
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.11 no.3
    • /
    • pp.136-150
    • /
    • 2008
  • Many studies have been carried out for automatic extraction of building by LiDAR data or airphoto. Combining the benefits of 3D location information data and shape information data of image can improve the accuracy. So, in this research building recognition algorithm based on contour was used to improve accuracy of building recognition by LiDAR data and elaborate building boundary recognition by airphoto. Building recognition algorithm based on contour can generate building boundary and roof structure information. Also it shows better accuracy of building detection than the existing recognition methods based on TIN or NDSM. Out of creating buffers in regular size on the building boundary which is presumed by contour, this research limits the boundary area of airphoto and elaborate building boundary to fit into edge of airphoto by double active contour. From the result of this research, 3D building boundary will be able to be detected by optimal matching on the constant range of extracted boundary in the future.

  • PDF

Edge Extraction Method Based on Color Image Model (컬러 영상 모델에 기반한 에지 추출기법)

  • Kim Tae-Eun
    • Journal of Digital Contents Society
    • /
    • v.4 no.1
    • /
    • pp.11-21
    • /
    • 2003
  • In computer vision, the goal of stereopsis is to determine the surface structure of real world form two or more perspective views of scene. It is similar to human visual system. We can avoid obstacles, recognize objects, and manipulate machine using three-dimensional information. Until recently, only gray-level images have been used as input to computation for depth determination, but the availability of color can further enhance the performance of computational stereopsis. There are many models to provide efficient color system. The simplest model, RGB model treats color as if it were composed of separate entities. Each color channel is processed individually by the same stereopsis module as used in the gray-level model. His Model decouples intensity component from color information. So it can deal with color properties without defect intensity information. Opponent color model is based on human visual system. In this model, the red-green-blue colors are combined into three opponent channels before further processing.

  • PDF

One-Dimensional Radar Scattering Center for Target Recognition of Ground Target in W-Band Millimeter Wave Seeker Considering Missile Flight-Path Scenario (유도탄 조우 시나리오를 고려한 W-대역 밀리미터파 탐색기의 지상 표적 식별을 위한 1차원 산란점 추출에 관한 연구)

  • Park, Sungho;Kim, Jihyun;Woo, Seon-Keol;Kwon, Jun-Beom;Kim, Hong-Rak
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.28 no.12
    • /
    • pp.982-992
    • /
    • 2017
  • In this paper, we introduce a method of selection for the optimal transmission polarization of a W-band seeker through the extraction of the one-dimensional scattering center of a ground tank target. We calculated the surface scattering and edge scattering using the shooting and bouncing ray tracing method of the CST A-solver. Based on 4-channel RCS data, using the one-dimensional RELAX algorithm, which is a kind of spectral estimation technique, scattering centers of ground targets were extracted. According to the changes in the polarization state and look angle, we compared and analyzed the scattering center results. Through simulation, we verified that the scattering center results can be applied when feature vectors are used for target recognition.

A Study on Scratch Detection of Semiconductor Package using Mask Image (마스크 이미지를 이용한 반도체 패키지 스크래치 검출 연구)

  • Lee, Tae-Hi;Park, Koo-Rack;Kim, Dong-Hyun
    • Journal of the Korea Convergence Society
    • /
    • v.8 no.11
    • /
    • pp.43-48
    • /
    • 2017
  • Semiconductors are leading the development of industrial technology, leading to miniaturization and weight reduction of electronic products as a leading technology, we are dragging the electronic industry market Especially, the semiconductor manufacturing process is composed of highly accurate and complicated processes, and effective production is required Recently, a vision system combining a computer and a camera is utilized for defect detection In addition, the demand for a system for measuring the shape of a fine pattern processed by a special process is rapidly increasing. In this paper, we propose a vision algorithm using mask image to detect scratch defect of semiconductor pockage. When applied to the manufacturing process of semiconductor packages via the proposed system, it is expected that production management can be facilitated, and efficiency of production will be enhanced by failure judgment of high-speed packages.

An Iris Detection Algorithm for Disease Prediction based Iridology (홍채학기반이 질병예측을 위한 홍채인식 알고리즘)

  • Cho, Young-bok;Woo, Sung-Hee;Lee, Sang-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.21 no.1
    • /
    • pp.107-114
    • /
    • 2017
  • Iris diagnosis is an alternative medicine to diagnose the disease of the patient by using different of the iris pattern, color and other characteristics. This paper proposed a disease prediction algorithm that using the iris regions that analyze iris change to using differential image of iris image. this method utilize as patient's health examination according to iris change. Because most of previous studies only find a sign pattern in a iris image, it's not enough to be used for a iris diagnosis system. We're developed an iris diagnosis system based on a iris images processing approach, It's presents the extraction algorithms of 8 major iris signs and correction manually for improving the accuracy of analysis. As a result, PNSR of applied edge detection image is about 132, and pattern matching area recognition presented practical use possibility by automatic diagnostic that presume situation of human body by iris about 91%.

Content-Based Image Retrieval using Region Feature Vector (영역 특징벡터를 이용한 내용기반 영상검색)

  • Kim Dong-Woo;Song Young-Jun;Kim Young-Gil;Ah Jae-Hyeong
    • The KIPS Transactions:PartB
    • /
    • v.13B no.1 s.104
    • /
    • pp.47-52
    • /
    • 2006
  • This paper proposes a method of content-based image retrieval using region feature vector in order to overcome disadvantages of existing color histogram methods. The color histogram methods have a weak point that reduces accuracy because of quantization error, and more. In order to solve this, we convert color information to HSV space and quantize hue factor being purecolor information and calculate histogram and then use thus for retrieval feature that is robust in brightness, movement, and rotation. Also we solve an insufficient part that is the most serious problem in color histogram methods by dividing an image into sixteen regions and then comparing each region. We improve accuracy by edge and DC of DCT transformation. As a result of experimenting with 1,000 color images, the proposed method has showed better precision than the existing methods.

An Implementation of Pattern Recognition Algorithm for Fast Paper Currency Counting (고속 지폐 계수를 위한 패턴 인식 알고리즘 구현)

  • Kim, Seon-Gu;Kang, Byeong-Gwon
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.39B no.7
    • /
    • pp.459-466
    • /
    • 2014
  • In this paper, we suggest an efficient image processing method for fast paper currency counting with pattern recognition. The patterns are consisted of feature data in each note object extracted from full reflection image of notes and a general contact image sensor(CIS) is used to aggregate the feature images. The proposed pattern recognition algorithm can endure image variation when the paper currency is scanned because it is not sensitive to changes of image resulting in successful note recognition. We tested 100 notes per denomination and currency of several countries including Korea, U.S., China, EU, Britain and Turkey. To ensure the reliability of the result, we tested a total of 10 times per each direction of notes. We can conclude that this algorithm will be applicable to commercial product because of its successful recognition rates. The 100% recognition rates are obtained in almost cases with exceptional case of 99.9% in Euro and 99.8% in Turkish Lira.

Skew correction of face image using eye components extraction (눈 영역 추출에 의한 얼굴 기울기 교정)

  • Yoon, Ho-Sub;Wang, Min;Min, Byung-Woo
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.33B no.12
    • /
    • pp.71-83
    • /
    • 1996
  • This paper describes facial component detection and skew correction algorithm for face recognition. We use a priori knowledge and models about isolated regions to detect eye location from the face image captured in natural office environments. The relations between human face components are represented by several rules. We adopt an edge detection algorithm using sobel mask and 8-connected labelling algorith using array pointers. A labeled image has many isolated components. initially, the eye size rules are used. Eye size rules are not affected much by irregular input image conditions. Eye size rules size, and limited in the ratio between gorizontal and vertical sizes. By the eye size rule, 2 ~ 16 candidate eye components can be detected. Next, candidate eye parirs are verified by the information of location and shape, and one eye pair location is decided using face models about eye and eyebrow. Once we extract eye regions, we connect the center points of the two eyes and calculate the angle between them. Then we rotate the face to compensate for the angle so that the two eyes on a horizontal line. We tested 120 input images form 40 people, and achieved 91.7% success rate using eye size rules and face model. The main reasons of the 8.3% failure are due to components adjacent to eyes such as eyebrows. To detect facial components from the failed images, we are developing a mouth region processing module.

  • PDF

Development of a Lane Detect Algorithm from Road-Facing Cameras on a Vehicle (차량에 부착된 측하방 CCD카메라를 이용한 차선추출 알고리즘 개발)

  • Rhee, Soo-Ahm;Lee, Tae-Yoon;Kim, Tae-Jung;Sung, Jung-Gon
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.13 no.3 s.33
    • /
    • pp.87-94
    • /
    • 2005
  • 3D positional information of lane can be automatically calculated tv combining GPS data, IMU data if coordinates of lane centers are given. The Road Safety Survey and Analysis Vehicle(RoSSAV) is currently under development to analyze three dimensional safety and stability of roads. RoSSAV has GPS and IMU sensors to get positional information of the vehicle and two road-facing CCD cameras for extraction of lane coordinates. In this paper, we develop technology that automatically detects centers of lanes from the road-facing cameras of RoSSAV. The proposed algorithm defines line-support regions by grouping pixels with similar edge orientation and magnitude together and extracts a line from each line support region by planar fitting. Then if extracted lines and the region in-between satisfy the criteria of brightness and width, we decide this region as lane. The proposed algorithm was more precise and stable than the previously proposed algorithm based on brightness threshold method. Experiments with real road scenes confirmed that lane was effectively extracted by the proposed algorithm.

  • PDF

Selective Histogram Matching of Multi-temporal High Resolution Satellite Images Considering Shadow Effects in Urban Area (도심지역의 그림자 영향을 고려한 다시기 고해상도 위성영상의 선택적 히스토그램 매칭)

  • Yeom, Jun-Ho;Kim, Yong-Il
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.20 no.2
    • /
    • pp.47-54
    • /
    • 2012
  • Additional high resolution satellite images, other period or site, are essential for efficient city modeling and analysis. However, the same ground objects have a radiometric inconsistency in different satellite images and it debase the quality of image processing and analysis. Moreover, in an urban area, buildings, trees, bridges, and other artificial objects cause shadow effects, which lower the performance of relative radiometric normalization. Therefore, in this study, we exclude shadow areas and suggest the selective histogram matching methods for image based application without supplementary digital elevation model or geometric informations of sun and sensor. We extract the shadow objects first using adjacency informations with the building edge buffer and spatial and spectral attributes derived from the image segmentation. And, Outlier objects like a asphalt roads are removed. Finally, selective histogram matching is performed from the shadow masked multi-temporal Quickbird-2 images.