• 제목/요약/키워드: normalization method

검색결과 640건 처리시간 0.025초

블록 기반 밝기 표준화를 통한 이진영상의 고속 불균일 조명 보정 (Fast Correction of Nonuniform Illumination on Bi-level Images using Block Based Intensity Normalization)

  • 정지혜;김정태
    • 전기학회논문지
    • /
    • 제61권12호
    • /
    • pp.1926-1931
    • /
    • 2012
  • We investigated a novel fast non-uniform illumination correction method for bi-level images. The proposed method divides a bi-level image into sub-images and roughly estimates block-wise illumination by low pass filtered maximum values of sub-images. After that, we apply bilinear interpolation using the block-wise illumination to estimate non-uniform illumination, and compensate for the effect of non-uniform illumination using the estimated illumination. Since the proposed method is not based on computation intensive iterative optimization, the proposed method can be used effectively for applications that require fast correction of non-uniform illumination. In simulations, the proposed method showed more than 20 times faster speed than existing entropy minimization method. Moreover, in simulations and experiments, the restored images by the proposed method were more close to true images than images restored by conventional method.

수정 Starburst 알고리즘과 Homography Normalization을 이용한 시선추적 (Gaze Tracking Using a Modified Starburst Algorithm and Homography Normalization)

  • 조태훈;강현민
    • 한국정보통신학회논문지
    • /
    • 제18권5호
    • /
    • pp.1162-1170
    • /
    • 2014
  • 본 논문에서는 두 개의 카메라를 이용하여 보다 정확한 동공 인식을 통한 원격방식의 시선 추적을 제안한다. 헤드 장착형 시선추적용으로 개발된 Starburst 알고리즘은 원격방식의 시선추적에서는 카메라가 보다 넓은 영역을 보기 때문에 눈썹, 눈꼬리 등 외란이 많아 스타버스트 알고리즘을 바로 적용하면 동공 중심 추출에 실패하는 경우가 많았다. 이에 템플렛매칭을 이용하여 대략적인 동공영역을 찾고, 찾은 영역 내에서만 스타버스트 알고리즘으로 동공의 경계 후보점들을 찾은 후 보완된 RANSAC 알고리즘으로 타원근사하여 동공의 중심을 추출하였다. 추출된 동공중심을 머리의 움직임에 거의 영향을 받지 않도록 4개의 적외선 LED를 모니터 네 구석에 부착하고 Homography normalization을 적용하였다. 스크린 좌표계로 변환할 때 기존에는 호모그래피를 사용하였으나, 카메라 렌즈의 비선형왜곡을 보상하기 위해 여기서는 고차다항식을 이용한 캘리브레이션 기법을 이용하였다. 끝으로, 두 대의 카메라를 사용하여 정확도와 신회성이 향상됨을 보인다.

조명 정규화 및 하이브리드 분류기를 이용한 계량기 숫자 인식 (Meter Numeric Character Recognition Using Illumination Normalization and Hybrid Classifier)

  • 오한글;조성원;정선태
    • 한국지능시스템학회논문지
    • /
    • 제24권1호
    • /
    • pp.71-77
    • /
    • 2014
  • 본 논문에서는 저조도 및 음영이 생기는 조명 환경하에서 성능이 개선된 계량기 숫자 인식 방법을 제안한다. 저조도 및 음영 문제를 해결하기 위해 LN(Local Normalization) 처리 기법을 이용한 조명 정규화를 수행한 후, 계량기 숫자 영역 검출과 3단계 계량기 숫자 분할이 이루어진다. 마지막으로 분할된 숫자 데이터를 분류하기 위한 하이브리드 숫자 분류기가 적용된다. 제안된 하이브리드 숫자 분류기는 역전파 신경망과 템플레이트 매칭의 연속 결합으로 이루어지고, 계량기 숫자 분류에 보다 강인한 휴리스틱 규칙에 의해 최종적으로 숫자를 분류한다. 저조도 및 음영 조명 환경하의 다양한 계량기 종류에 대해 직접 촬영하여 자체 제작한 계량기 이미지 데이터베이스에 기반한 실험을 통해 본 논문에서 제안한 숫자 인식 방법을 평가하고, 제안된 계량기 숫자 인식 방법이 효과적으로 잘 동작함을 확인하였다.

연결 성분 분석과 크기 정규화를 이용한 도로 노면 표시와 숫자 인식 (Recognition of Road Surface Marks and Numbers Using Connected Component Analysis and Size Normalization)

  • 정민철
    • 반도체디스플레이기술학회지
    • /
    • 제21권1호
    • /
    • pp.22-26
    • /
    • 2022
  • This paper proposes a new method for the recognition of road surface marks and numbers. The proposed method designates a region of interest on the road surface without first detecting a lane. The road surface markings are extracted by location and size using a connection component analysis. Distortion due to the perspective effect is minimized by normalizing the size of the road markings. The road surface marking of the connected component is recognized by matching it with the stored road marking templates. The proposed method is implemented using C language in Raspberry Pi 4 system with a camera module for a real-time image processing. The system was fixedly installed in a moving vehicle, and it recorded a video like a vehicle black box. Each frame of the recorded video was extracted, and then the proposed method was tested. The results show that the proposed method is successful for the recognition of road surface marks and numbers.

Comparison of Performance According to Preprocessing Methods in Estimating %IMF of Hanwoo Using CNN in Ultrasound Images

  • Kim, Sang Hyun
    • International journal of advanced smart convergence
    • /
    • 제11권2호
    • /
    • pp.185-193
    • /
    • 2022
  • There have been various studies in Korea to develop a %IMF(Intramuscular Fat Percentage) estimation method suitable for Hanwoo. Recently, a %IMF estimation method using a convolutional neural network (CNN), a kind of deep learning method among artificial intelligence methods, has been studied. In this study, we performed a performance comparison when various preprocessing methods were applied to the %IMF estimation of ultrasound images using CNN as mentioned above. The preprocessing methods used in this study are normalization, histogram equalization, edge enhancement, and a method combining normalization and edge enhancement. When estimating the %IMF of Hanwoo by the conventional method that did not apply preprocessing in the experiment, the accuracy was 98.2%. The other hand, we found that the accuracy improved to 99.5% when using preprocessing with histogram equalization alone or combined regularization and edge enhancement.

참조용어(Reference Terminology) 모델 확장을 위한 한의학용어 정형화(Normalization) 연구 (A study of Traditional Korean Medicine(TKM) term's Normalization for Enlarged Reference terminology model)

  • 전병욱;홍성천
    • 대한한의정보학회지
    • /
    • 제15권2호
    • /
    • pp.1-6
    • /
    • 2009
  • The discipline of terminology is based on its own theoretical principles and consists primarily of the following aspects: analysing the concepts and concept structures used in a field or domain of activity, identifying the terms assigned to the concepts, in the case of bilingual or multilingual terminology, establishing correspondences between terms in the various languages, creating new terms, as required. The word properties has syntax, morphology and orthography. The syntax is that how words are put together. The morphology is consist of inflection, derivation, and compounding. The orthography is spelling. Otherwise, the terms of TKM(Traditional Korean Medicine) is two important element of visual character and phonetic notation. A visual character consist of spell, sort words, stop words, etc. For example, that is a case of sort words in which this '다한', '한다', '多汗', '汗多' as same. A phonetic notation consist of palatalization, initial law, etc. For example, that is a case of palatalization in which this '수족랭', '수족냉', '手足冷', '手足冷' as same. Therefore, to enlarged reference terminology is a method by term's normalization. For such a reason, TKM's terms of normalization is necessary.

  • PDF

음성인식을 위한 성도 길이 정규화 (Vocal Tract Length Normalization for Speech Recognition)

  • 지상문
    • 한국정보통신학회논문지
    • /
    • 제7권7호
    • /
    • pp.1380-1386
    • /
    • 2003
  • 화자들 사이의 성도의 길이의 변이에 의하여 음성 인식기의 성능이 저하된다. 본 연구에서는 입력 음성에서 추출한 단구간 스펙트럼의 주파수축을 확대하거나 축소하여 음성인식기에 미치는 화자사이의 성도 길이의 영향을 최소화하는 방법을 사용한다 성도의 길이를 정규화하기 위한 주파수 변환 함수로서, 선형의 주파수 변환 함수와 조각적 선형적인 변환 함수를 고려하였다. 또한, 커다란 성도길이의 변이에 따른 주파수축의 척도변화를 보다 효과적으로 모의할 수 있는 가변구간 조각적 선형함수를 제안한다. TIDIGITS 연결 숫자음 음성자료에 대하여 제안한 방법을 적용한 결과, 단어의 오인식률을 2.15%에서 0.53%로 크게 감소시킴으로서, 성도 길이 정규화가 화자 독립 음성인식기의 성능 향상에 필수적임을 알 수 있었다.

호감도 함수 기반 다특성 강건설계 최적화 기법 (A Desirability Function-Based Multi-Characteristic Robust Design Optimization Technique)

  • 박종필;조재훈;남윤의
    • 산업경영시스템학회지
    • /
    • 제46권4호
    • /
    • pp.199-208
    • /
    • 2023
  • Taguchi method is one of the most popular approaches for design optimization such that performance characteristics become robust to uncontrollable noise variables. However, most previous Taguchi method applications have addressed a single-characteristic problem. Problems with multiple characteristics are more common in practice. The multi-criteria decision making(MCDM) problem is to select the optimal one among multiple alternatives by integrating a number of criteria that may conflict with each other. Representative MCDM methods include TOPSIS(Technique for Order of Preference by Similarity to Ideal Solution), GRA(Grey Relational Analysis), PCA(Principal Component Analysis), fuzzy logic system, and so on. Therefore, numerous approaches have been conducted to deal with the multi-characteristic design problem by combining original Taguchi method and MCDM methods. In the MCDM problem, multiple criteria generally have different measurement units, which means that there may be a large difference in the physical value of the criteria and ultimately makes it difficult to integrate the measurements for the criteria. Therefore, the normalization technique is usually utilized to convert different units of criteria into one identical unit. There are four normalization techniques commonly used in MCDM problems, including vector normalization, linear scale transformation(max-min, max, or sum). However, the normalization techniques have several shortcomings and do not adequately incorporate the practical matters. For example, if certain alternative has maximum value of data for certain criterion, this alternative is considered as the solution in original process. However, if the maximum value of data does not satisfy the required degree of fulfillment of designer or customer, the alternative may not be considered as the solution. To solve this problem, this paper employs the desirability function that has been proposed in our previous research. The desirability function uses upper limit and lower limit in normalization process. The threshold points for establishing upper or lower limits let us know what degree of fulfillment of designer or customer is. This paper proposes a new design optimization technique for multi-characteristic design problem by integrating the Taguchi method and our desirability functions. Finally, the proposed technique is able to obtain the optimal solution that is robust to multi-characteristic performances.

대용량 필기체 문자 인식을 위한 비선형 형태 정규화 방법의 정량적 평가 (Quantitative Evaluation of Nonlinear Shape Normalization Methods for the Recognition of Large-Set Handwrittern Characters)

  • 이성환;박정선
    • 전자공학회논문지B
    • /
    • 제30B권9호
    • /
    • pp.84-93
    • /
    • 1993
  • Recently, several nonlinear shape normalization methods have been proposed in order to compensate for the shape distortions in handwritten characters. In this paper, we review these nonlinear shape normalization methods from the two points of view : feature projection and feature density equalization. The former makes feature projection histogram by projecting a certain feature at each point of input image into horizontal-or vertical-axis and the latter equalizes the feature densities of input image by re-sampling the feature projection histogram. A systematic comparison of these methods has been made based on the following criteria: recognition rate, processing speed, computational complexity and measure of variation. Then, we present the result of quantitative evaluation of each method based on these criteria for a large variety of handwritten Hangul syllables.

  • PDF

코퍼스 기반 프랑스어 텍스트 정규화 평가 (Corpus-based evaluation of French text normalization)

  • 김선희
    • 말소리와 음성과학
    • /
    • 제10권3호
    • /
    • pp.31-39
    • /
    • 2018
  • This paper aims to present a taxonomy of non-standard words (NSW) for developing a French text normalization system and to propose a method for evaluating this system based on a corpus. The proposed taxonomy of French NSWs consists of 13 categories, including 2 types of letter-based categories and 9 types of number-based categories. In order to evaluate the text normalization system, a representative test set including NSWs from various text domains, such as news, literature, non-fiction, social-networking services (SNSs), and transcriptions, is constructed, and an evaluation equation is proposed reflecting the distribution of the NSW categories of the target domain to which the system is applied. The error rate of the test set is 1.64%, while the error rate of the whole corpus is 2.08%, reflecting the NSW distribution in the corpus. The results show that the literature and SNS domains are assessed as having higher error rates compared to the test set.