• Title/Summary/Keyword: 영상 전처리

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A Real-Time Hardware Architecture for Image Rectification Using Floating Point Processing (부동 소수점 연산을 이용한 실시간 영상 편위교정 FPGA 하드웨어 구조 설계)

  • Han, Dongil;Choi, Jeahoon;Shin, Ho Chul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.2
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    • pp.102-113
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    • 2014
  • This paper suggests a novel hardware architecture of a real-time rectification which is to remove vertical parallax of an image occurred in the pre-processing stage of stereo matching. As an off-line step, Matlab Toolbox which was designed by J.Y Bouguet, was used to calculate calibration parameter of the image. Then, based on the Heikkila and Silven's algorithm, rectification hardware was designed. At this point, to enhance the precision of the rectified image, floating-point unit was generated by using Xilinx Core Generator. And, we confirmed that proposed hardware design had higher precision compared to other designs while having the ability to do rectification in real-time.

Digital video watermarking using fingerprint data (동영상 스트리밍 인증을 위한 지문 기반 워터마킹)

  • Jung, Soo-Yeun;Lee, Dong-Eun;Lee, Seong-Won;Paik, Joon-Ki
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.44 no.6
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    • pp.43-50
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    • 2007
  • In this paper we propose a method that identifies users at H.264 streaming using watermarking with fingerprints. The watermark can efficiently reduce the potential danger of forgery or alteration. Especially a biometric watermark has various advantages. Among entire biometric characteristics, the fingerprint is the most convenient and economical. In this paper we propose a novel fingerprint-based watermarking technique that can survive under very low bit-rate compression. The proposed algorithm consists of enhancement of a fingerprint image, the watermark generation using the extracted feature coordinates, watermark insertion using discrete wavelet transform, and authentication. The proposed algorithm can achieve robust watermark extraction against 0.264 compressed videos.

The Character Area Extraction and the Character Segmentation on the Color Document (칼라 문서에서 문자 영역 추출믹 문자분리)

  • 김의정
    • Journal of the Korean Institute of Intelligent Systems
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    • v.9 no.4
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    • pp.444-450
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    • 1999
  • This paper deals with several methods: the clustering method that uses k-means algorithm to abstract the area of characters on the image document and the distance function that suits for the HIS coordinate system to cluster the image. For the prepossessing step to recognize this, or the method of characters segmentate, the algorithm to abstract a discrete character is also proposed, using the linking picture element. This algorithm provides the feature that separates any character such as the touching or overlapped character. The methods of projecting and tracking the edge have so far been used to segment them. However, with the new method proposed here, the picture element extracts a discrete character with only one-time projection after abstracting the character string. it is possible to pull out it. dividing the area into the character and the rest (non-character). This has great significance in terms of processing color documents, not the simple binary image, and already received verification that it is more advanced than the previous document processing system.

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Illumination estimation based on valid pixel selection from CCD camera response (CCD카메라 응답으로부터 유효 화소 선택에 기반한 광원 추정)

  • 권오설;조양호;김윤태;송근호;하영호
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.5
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    • pp.251-258
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    • 2004
  • This paper proposes a method for estimating the illuminant chromaticity using the distributions of the camera responses obtained by a CCD camera in a real-world scene. Illuminant estimation using a highlight method is based on the geometric relation between a body and its surface reflection. In general, the pixels in a highlight region are affected by an illuminant geometric difference, camera quantization errors, and the non-uniformity of the CCD sensor. As such, this leads to inaccurate results if an illuminant is estimated using the pixels of a CCD camera without any preprocessing. Accordingly, to solve this problem the proposed method analyzes the distribution of the CCD camera responses and selects pixels using the Mahalanobis distance in highlight regions. The use of the Mahalanobis distance based on the camera responses enables the adaptive selection of valid pixels among the pixels distributed in the highlight regions. Lines are then determined based on the selected pixels with r-g chromaticity coordinates using a principal component analysis(PCA). Thereafter, the illuminant chromaticity is estimated based on the intersection points of the lines. Experimental results using the proposed method demonstrated a reduced estimation error compared with the conventional method.

Generation of Digital Orthoimage using Direct Georeferencing (외부표정요소 직접결정에 의한 수치정사영상 생성)

  • Song Youn-Kyung
    • Spatial Information Research
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    • v.13 no.1 s.32
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    • pp.55-63
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    • 2005
  • Direct Georeferencing(DG) Is based on the direct measurement of the projection centers and rotation angle of sensor through loading the GPS and INS in aircraft. The methods can offer us to acquire the exterior orientation parameters with only minimum GCPs, even the ground control process could be completely skipped. Hence, as long as securing Digital Elevation Model (DEM), it is feasible to generate digital orthophotos without performing the aerial triangulation with Ground Control Point (GCP) surveying. In this study, the DEM is automatically generated by using a image matching technique based on aerial photos and exterior orientation parameters. This is followed by producing an orthophoto from these results. Finally, accuracy analysis of the georeferencing technique for generating orthoimage indicates that RMS errors of 62cm and 76cm occurred at the X and the Y axis, respectively. This means that the results fulfill the demanding accuracy of the 1:5000 digital map. Hence, it is possible to conclude from this study that the direct georeferencing based orthoimage generation method is able to effectively digital map update.

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Hardware Design of LBP Operation for Real-time Face Detection of HD Images (HD 영상의 실시간 얼굴 검출을 위한 LBP 연산의 하드웨어 설계)

  • Noh, Hyun-Jin;Kim, Tae-Wan;Chung, Yum-Mo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.48 no.10
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    • pp.67-71
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    • 2011
  • Existing face detection systems, which are used for digital door locks, digital cameras, video surveillance systems, and so on, are software-based implementation for relatively low level resolution images. Therefore, in this case, there are difficulties in detecting faces in a real-time fashion due to the increasing amount of operational processing as well as in allowing the requirements of face detections for HD(High Definition) resolutions. A hardware approach is necessary to efficiently find faces for HD images in real-time embedded systems. This paper proposes and implements a hardware architecture for an LBP(Local Binary Pattern) operation which is a time-consuming part as one of preprocessing steps for face detection. The hardware architecture proposed in this research has been implemented and tested with a FPGA(Field Programmable Gate Array) chip, and shown that the approach guarantees efficient face detection for HD images.

Semi-automatic Building Area Extraction based on Improved Snake Model (개선된 스네이크 모텔에 기반한 반자동 건물 영역 추출)

  • Park, Hyun-Ju;Gwun, Ou-Bong
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.48 no.1
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    • pp.1-7
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    • 2011
  • Terrain, building location and area, and building shape information is in need of implementing 3D map. This paper proposes a method of extracting a building area by an improved semi-automatic snake algorithm. The method consists of 3-stage: pre-processing, initializing control points, and applying an improved snake algorithm. In the first stage, after transforming a satellite image to a gray image and detecting the approximate edge of the gray image, the method combines the gray image and the edge. In the second stage, the user looks for the center point of a building and the system sets the circular or rectangular initial control points by an procedural method. In the third stage, the enhanced snake algorithm extracts the building area. In particular, this paper sets the one tenn of the snake in a new way in order to use the proposed method for specializing building area extraction. Finally, this paper evaluated the performance of the proposed method using sky view satellite image and it showed that the matching percentage to the exact building area is 75%.

The Amur starfishes recognition using the adaptive filter (적응형 필터를 이용한 아무르 불가사리 인식)

  • Kim, Jong Ik;Shim, Hyun Bo;Kim, Sung Rak
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.4
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    • pp.922-934
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    • 2013
  • The Amur Starfishes, known as give huge damages to shellfish farms, are being removed by only divers and fish net in the wide areas. Therefore, increasing recognition rates of starfishes are desperately required to remove high amounts of Amur Starfishes effectively. Meanwhile, current technology of obtaining the images of starfish distribution has limitation of obtaining color images due to using visible light in the darkness seabed area. In this research, we have used infrared ray, which is very penetrated, and strong against noise that comes from floating objects under the water, in order to solve current problems. As a result, we have acquired better images to analyze recognition rates of starfishes, and also able to received much satisfied recognition rate results for 88.7% of Amur Starfishes by adopting the most suitable adaptive filter method.

Development of Identification Method of Rice Varieties Using Image Processing Technique (화상처리법에 의한 쌀 품종별 판별기술 개발)

  • Kwon, Young-Kil;Cho, Rae-Kwang
    • Applied Biological Chemistry
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    • v.41 no.2
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    • pp.160-165
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    • 1998
  • Current discriminating technique of rice variety is known to be not objective till this time because of depending on naked eye of well trained inspector. DNA finger print method based on genetic character of rice has been indicated inappropriate for on-site application, because the method need much labor and skilled expert. The purpose of this study was to develops the identification technique of polished rice varieties using CCD camera images. To minimize the noise of the captured image, thresholding and median filtering were carried out, and edge was extracted from the image data. Image data after pretreatment of normalize and FFT(fast fourier transform) were used for library model and feedforward backpropagation neural network model. Image processing technique using CCD camera could discriminate the variety of rice with high accuracy in case of quite different rice of shape, but the accuracy was reached at 85% in the similar shape of rice.

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Feature Extraction in an Aerial Photography of Gimnyeong Sand Dune Area by Texture Filtering (항공사진의 질감 분석을 통한 김녕사구지역의 지형지물 추출)

  • Chang Eun-Mi;Park Kyeong
    • Journal of the Korean Geographical Society
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    • v.41 no.2 s.113
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    • pp.139-149
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    • 2006
  • Earlier research works focused on the seasonal patterns and bio-geochemical processes in sand dunes, and the satellite data and aerial photographs have been used only as a backdrop or for the multi-temporal delineation of sand dune area. In order to find the optimal way to extract features' characteristics, Gimnyeong sand dune area was selected as a study site. Field works have been carried out three times to collect ground control points and sand samples for laboratory analyses. The texture of sand dune is classified as fine sand, which has been derived from shell fragments. The sand dune penetrated into the island from northwest to southeast direction. An aerial photograph was re-sampled into one-meter resolution and rectified with software including Erdas Imagine and ENVI. Sub-scenes were chosen as samples for sand dune, urban area and rural area. K-group non-parametric analysis had been done for the geometric and spectral values of enclosed texture patches. Urban areas proved to have significant smaller patches than the others.