• Title/Summary/Keyword: Illumination compensation

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Vision based MLGA Chip Mounting System (Vision을 이용한 MLGA Chip 장착시스템 개발)

  • No, Byeong-Ok;Yu, Yeong-Gi;Kim, An-Sik;Kim, Yeong-Su
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.11
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    • pp.161-167
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    • 2001
  • In this study, the control of mounting system for MLGA package was developed using machine vision for the control of rotation position compensation and mounting position of X-Y table. Two types of materials, polymer and alumina, were used for the dielectric insulator of the MLGA. The illumination system and the algorithm of position compensation which is suitable for these materials was developed. We found that the mounting accuracy enough to the degree of${\pm}10{\mu}m$ when MLGA was mounted on the PCB.

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Normalization of Face Images Subject to Directional Illumination using Linear Model (선형모델을 이용한 방향성 조명하의 얼굴영상 정규화)

  • 고재필;김은주;변혜란
    • Journal of KIISE:Software and Applications
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    • v.31 no.1
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    • pp.54-60
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    • 2004
  • Face recognition is one of the problems to be solved by appearance based matching technique. However, the appearance of face image is very sensitive to variation in illumination. One of the easiest ways for better performance is to collect more training samples acquired under variable lightings but it is not practical in real world. ]:n object recognition, it is desirable to focus on feature extraction or normalization technique rather than focus on classifier. This paper presents a simple approach to normalization of faces subject to directional illumination. This is one of the significant issues that cause error in the face recognition process. The proposed method, ICR(illumination Compensation based on Multiple Linear Regression), is to find the plane that best fits the intensity distribution of the face image using the multiple linear regression, then use this plane to normalize the face image. The advantages of our method are simple and practical. The planar approximation of a face image is mathematically defined by the simple linear model. We provide experimental results to demonstrate the performance of the proposed ICR method on public face databases and our database. The experimental results show a significant improvement of the recognition accuracy.

RECOGNITION ALGORITHM OF DRIED OAK MUSHROOM GRADINGS USING GRAY LEVEL IMAGES

  • Lee, C.H.;Hwang, H.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1996.06c
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    • pp.773-779
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    • 1996
  • Dried oak mushroom have complex and various visual features. Grading and sorting of dried oak mushrooms has been done by the human expert. Though actions involved in human grading looked simple, a decision making underneath the simple action comes from the result of the complex neural processing of the visual image. Through processing details involved in human visual recognition has not been fully investigated yet, it might say human can recognize objects via one of three ways such as extracting specific features or just image itself without extracting those features or in a combined manner. In most cases, extracting some special quantitative features from the camera image requires complex algorithms and processing of the gray level image requires the heavy computing load. This fact can be worse especially in dealing with nonuniform, irregular and fuzzy shaped agricultural products, resulting in poor performance because of the sensitiveness to the crisp criteria or specific ules set up by algorithms. Also restriction of the real time processing often forces to use binary segmentation but in that case some important information of the object can be lost. In this paper, the neuro net based real time recognition algorithm was proposed without extracting any visual feature but using only the directly captured raw gray images. Specially formated adaptable size of grids was proposed for the network input. The compensation of illumination was also done to accomodate the variable lighting environment. The proposed grading scheme showed very successful results.

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Face Detection based on Pupil Color Distribution Maps with the Frequency under the Illumination Variance (빈도수를 고려한 눈동자색 분포맵에 기반한 조명 변화에 강건한 얼굴 검출 방법)

  • Cho, Han-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.5
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    • pp.225-232
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    • 2009
  • In this paper, a new face detection method based on pupil color distribution maps with the frequency under the illumination variance is proposed. Face-like regions are first extracted by applying skin color distribution maps to a color image and then, they are reduced by using the standard deviation of chrominance components. In order to search for eye candidates effectively, the proposed method extracts eye-like regions from face-like regions by using pupil color distribution maps. Furthermore, the proposed method is able to detect eyes very well by segmenting the eye-like regions, based on a lighting compensation technique and a segmentation algorithm even though face regions are changed into dark-tone due to varying illumination conditions. Eye candidates are then detected by means of template matching method. Finally, face regions are detected by using the evaluation values of two eye candidates and a mouth. Experimental results show that the proposed method can achieve a high performance.

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An Illumination-Robust Driver Monitoring System Based on Eyelid Movement Measurement (조명에 강인한 눈꺼풀 움직임 측정기반 운전자 감시 시스템)

  • Park, Il-Kwon;Kim, Kwang-Soo;Park, Sangcheol;Byun, Hye-Ran
    • Journal of KIISE:Software and Applications
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    • v.34 no.3
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    • pp.255-265
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    • 2007
  • In this paper, we propose a new illumination-robust drowsy driver monitoring system with single CCD(Charge Coupled Device) camera for intelligent vehicle in the day and night. For this system that is monitoring driver's eyes during a driving, the eye detection and the measure of eyelid movement are the important preprocesses. Therefore, we propose efficient illumination compensation algorithm to improve the performance of eye detection and also eyelid movement measuring method for efficient drowsy detection in various illumination. For real-time application, Cascaded SVM (Cascaded Support Vector Machine) is applied as an efficient eye verification method in this system. Furthermore, in order to estimate the performance of the proposed algorithm, we collect video data about drivers under various illuminations in the day and night. Finally, we acquired average eye detection rate of over 98% about these own data, and PERCLOS(The percentage of eye-closed time during a period) are represented as drowsy detection results of the proposed system for the collected video data.

Hybrid Neural Classifier Combined with H-ART2 and F-LVQ for Face Recognition

  • Kim, Do-Hyeon;Cha, Eui-Young;Kim, Kwang-Baek
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1287-1292
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    • 2005
  • This paper presents an effective pattern classification model by designing an artificial neural network based pattern classifiers for face recognition. First, a RGB image inputted from a frame grabber is converted into a HSV image which is similar to the human beings' vision system. Then, the coarse facial region is extracted using the hue(H) and saturation(S) components except intensity(V) component which is sensitive to the environmental illumination. Next, the fine facial region extraction process is performed by matching with the edge and gray based templates. To make a light-invariant and qualified facial image, histogram equalization and intensity compensation processing using illumination plane are performed. The finally extracted and enhanced facial images are used for training the pattern classification models. The proposed H-ART2 model which has the hierarchical ART2 layers and F-LVQ model which is optimized by fuzzy membership make it possible to classify facial patterns by optimizing relations of clusters and searching clustered reference patterns effectively. Experimental results show that the proposed face recognition system is as good as the SVM model which is famous for face recognition field in recognition rate and even better in classification speed. Moreover high recognition rate could be acquired by combining the proposed neural classification models.

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Defect Detection of Flat Panel Display Using Wavelet Transform (웨이블릿 변환을 이용한 FPD 결함 검출)

  • Kim, Sang-Ji;Lee, Youn-Ju;Yoon, Jeong-Ho;You, Hun;Lee, Byung-Gook;Lee, Joon-Jae
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.10 no.1
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    • pp.47-60
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    • 2006
  • Due to the uneven illumination of FPD panel surface, it is difficult to detect the defects. The paper proposes a method to find the uneven illumination compensation using wavelets, which are done based on multi-resolution structure. The first step is to decompose the image into multi-resolution levels. Second, elimination of lowest smooth sub-image with highest frequency band removes the high frequency noise and low varying illumination. In particular, the main algorithm was implemented by lifting scheme for realtime inline process.

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Anomaly Sewing Pattern Detection for AIoT System using Deep Learning and Decision Tree

  • Nguyen Quoc Toan;Seongwon Cho
    • Smart Media Journal
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    • v.13 no.2
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    • pp.85-94
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    • 2024
  • Artificial Intelligence of Things (AIoT), which combines AI and the Internet of Things (IoT), has recently gained popularity. Deep neural networks (DNNs) have achieved great success in many applications. Deploying complex AI models on embedded boards, nevertheless, may be challenging due to computational limitations or intelligent model complexity. This paper focuses on an AIoT-based system for smart sewing automation using edge devices. Our technique included developing a detection model and a decision tree for a sufficient testing scenario. YOLOv5 set the stage for our defective sewing stitches detection model, to detect anomalies and classify the sewing patterns. According to the experimental testing, the proposed approach achieved a perfect score with accuracy and F1score of 1.0, False Positive Rate (FPR), False Negative Rate (FNR) of 0, and a speed of 0.07 seconds with file size 2.43MB.

Design of Fuzzy Controller for Vision-based Arm Robot (비전기반 암 로봇의 퍼지제어기 설계)

  • Shin, Hwa-Young;Kim, Young-Joong;Lim, Myo-Taeg
    • Proceedings of the KIEE Conference
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    • 2002.11c
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    • pp.485-488
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    • 2002
  • In this paper, fuzzy logic controllers are designed for compensation of distance errors. Because we can't know information of the depth in a mono camera, these errors are occurred. Also, they are increased as a target object is to keep away from a center of image. Therefore, the errors for each position of joints of an arm robot should be modeled, but accurate models can't be obtained because of no information of the depth, uncertain feature points of image, parameter uncertainties, and illumination. Hence, fuzzy logic controllers for each error are designed for compensation. This paper consists of color image processing, error modeling, and the controller design. Experimental results are given to verify the effectiveness of our proposed method.

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New Illumination compensation algorithm improving a multi-view video coding performance by advancing its temporal and inter-view correlation (다시점 비디오의 시공간적 중복도를 높여 부호화 성능을 향상시키는 새로운 조명 불일치 보상 기법)

  • Lee, Dong-Seok;Yoo, Ji-Sang
    • Journal of Broadcast Engineering
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    • v.15 no.6
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    • pp.768-782
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    • 2010
  • Because of the different shooting position between multi-view cameras and the imperfect camera calibration, Illumination mismatches of multi-view video can happen. This variation can bring about the performance decrease of multi-view video coding(MVC) algorithm. A histogram matching algorithm can be applied to recompensate these inconsistencies in a prefiltering step. Once all camera frames of a multi-view sequence are adjusted to a predefined reference through the histogram matching, the coding efficiency of MVC is improved. However the histogram distribution can be different not only between neighboring views but also between sequential views on account of movements of camera angle and some objects, especially human. Therefore the histogram matching algorithm which references all frames in chose view is not appropriate for compensating the illumination differences of these sequence. Thus we propose new algorithms both the image classification algorithm which is applied two criteria to improve the correlation between inter-view frames and the histogram matching which references and matches with a group of pictures(GOP) as a unit to advance the correlation between successive frames. Experimental results show that the compression ratio for the proposed algorithm is improved comparing with the conventional algorithms.