• 전기학회논문지
• /
• 제58권4호
• /
• pp.806-816
• /
• 2009

Character recognition system consists of four step; text localization, text segmentation, character segmentation, and recognition. The character segmentation is very important and difficult because of noise, illumination, and so on. For high recognition rates of the system, it is necessary to take good performance of character segmentation algorithm. Many algorithms for character segmentation have been developed up to now, and many people have been recently making researches in segmentation of touching or overlapping character. Most of algorithms cannot apply to the text regions of management number marked on the slab in steel image, because the text regions are irregular such as touching character by strong illumination and by trouble of nozzle in marking machine, and loss of character. It is difficult to gain high success rate in various cases. This paper describes a new algorithm of character segmentation to recognize slab management number marked on the slab in the steel image. It is very important that pre-processing step is to convert gray image to binary image without loss of character and touching character. In this binary image, non-touching characters are simply separated by using vertical projection profile. For separating touching characters, after we use combined profile to find candidate points of boundary, decide real character boundary by using method based on recognition. In recognition step, we remove noise of character images, then recognize respective character images. In this paper, the proposed algorithm is effective for character segmentation and recognition of various text regions on the slab in steel image.

• Journal of the Korean Data and Information Science Society
• /
• 제14권3호
• /
• pp.525-533
• /
• 2003

In this paper we introduce some existing preprocessing algorithm for character recognition and consider feature extraction method for the recognition of low resolution document. Image recognition of low resolution document including fax images can be frequently misclassified due to the blurring effect, slope effect, noise and so on. In order to overcome these difficulties in the character recognition we considered a mesh feature extraction and contour direction code feature. System for automatic character recognition were suggested.

• 한국융합학회논문지
• /
• 제11권6호
• /
• pp.1-6
• /
• 2020

본 연구에서는 컴퓨터 비전의 분야 중 하나인 문자 인식에 관한 연구를 수행했다. 대표적인 문자인식 기법 중 하나인 광학식 문자 판독 기법의 경우 일정한 규격과 서식에서 벗어나게 되면 인식률이 떨어진다는 한계점이 있다. 따라서 본 연구에서는 딥 러닝 기법을 적용해 이러한 문제점을 해결하고자 한다. 또한 기존의 문자 인식 연구의 경우 대부분 영어 및 숫자 인식에 국한되어 있다. 따라서 본 연구는 한글 인식을 위한 딥 러닝 기반 문자 인식 알고리즘을 제시한다. 알고리즘은 1-NED 평가 방법에서 0.841의 점수를 얻었으며, 이는 영어 인식 결과와 비슷한 수치이다. 본 연구를 통해 딥 러닝 기반 한글 인식 알고리즘의 성능을 확인할 수 있으며, 이를 통해 향후 연구방향에 대해 제시한다.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
• /
• pp.68-73
• /
• 2000

This study to embody automatic recognition of VIN(Vehicle Identification Number)character by computer vision system. Automatic recognition characters methods consist of the thining processing and the recognition of each character. VIN character and background classified using counting method of the size of connected pixels. Thining processing applied to segmentation of connected fundamental phonemes by Hilditch's algorithm. Each VIN character contours tracing algorithm used the Freeman's direction tracing algorithm.

• KIEE International Transaction on Systems and Control
• /
• 제12D권1호
• /
• pp.27-32
• /
• 2002

In this paper, we would study the applicability of neural networks to the recognition process of Korean stenographic character image, applying the classification function, which is the greatest merit of those of neural networks applied to the various parts so far, to the stenographic character recognition, relatively simple classification work. Korean stenographic recognition algorithms, which recognize the characters by using some methods, have a quantitative problem that despite the simplicity of the structure, a lot of basic characters are impossible to classify into a type. They also have qualitative one that It Is not easy to classify characters fur the delicacy of the character farms. Even though this is the result of experiment under the limited environment of the basic characters, this shows the possibility that the stenographic characters can be recolonized effectively by neural network system. In this system, we got 90.86% recognition rate as an average.

• International Journal of Ocean System Engineering
• /
• 제2권1호
• /
• pp.16-23
• /
• 2012

In this paper we discussed a new methodology for Urdu Character Recognition system using Dempster-Shafer theory which can powerfully estimate the similarity ratings between a recognized character and sampling characters in the character database. Recognition of character is done by five probability calculation methods such as (similarity, hamming, linear correlation, cross-correlation, nearest neighbor) with Dempster-Shafer theory of belief functions. The main objective of this paper is to Recognition of Urdu letters and numerals through five similarity and dissimilarity algorithms to find the similarity between the given image and the standard template in the character recognition system. In this paper we develop a method to combine the results of the different distance measurement methods using the Dempster-Shafer theory. This idea enables us to obtain a single precision result. It was observed that the combination of these results ultimately enhanced the success rate.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 하계학술대회 논문집 D
• /
• pp.2515-2517
• /
• 2002

The process of character recognition goes through 5 steps; image acquisition, character region extraction, preprocessing, character region segmentation, character recognition. Therefore the final recognition rate of character recognition is directly affected by the performance of each step. This paper is a leading research for object recognition using image processing algorithm which is one of the field of study in computer vision. And this paper will suggest an algorithm to extract the portion of number chain, which is part of the research embodying a system to perceive the data of manufacture and the name of the producer on the wrapping of groceries. In addition, this can extract the number chain comparatively accurate without using many complex algorithm by diving and extracting the moving number region at the same time.

• 정보처리학회논문지B
• /
• 제9B권3호
• /
• pp.375-382
• /
• 2002

필기체 문자 인식은 온라인 필기체 문자 인식과 오프라인 필기체 문자 인식으로 나누어진다. 온라인 필기체 문자 인식은 타블렛과 같은 펜 기반의 전자식 입력 장치를 이용하여 필기의 순서와 획의 위치와 같은 동적인 필기 정보를 문자의 입력 시 획득할 수 있어 오프라인 필기체 문자 인식에 비해 큰 연구 성과를 이루었다. 그러나 오프라인 필기체 문자 인식은 온라인 필기체 문자 인식에서와 같이 동적인 정보를 입력받을 수 없고, 다양한 필기와 자소의 겹침이 심하며 획 사이의 잡영을 많이 가지고 있어 인식의 전처리 결과에 따라 인식 성능이 크게 달라진다. 본 논문에서는 오프라인 필기체 한글 문자 인식을 위해 문자의 동적인 정보를 포함하는 획을 효과적으로 추출하는 방법을 제안한다. 제안된 방법은 전처리 과정으로 먼저 Watershed 알고리즘을 이용하여 입력된 필기체 문자 영상의 향상 및 이진화를 수행한다. 이진화된 문자부를 변형된 Lu와 Wang의 세선화 알고리즘을 사용하여 세선화를 수행한 후 문자에서의 특징점을 추출하여 세그먼트 화소열을 추출하고, 최대 허용 오차법을 이용하여 벡터화한다. 벡터화의 수행으로 몇 개의 획이 하나의 세그먼트로 묶인 경우, 하나의 세그먼트 화소열은 2 또는 그 이상의 세그먼트 벡터로 분리된다. 추출된 세그먼트 벡터들을 완전한 획으로 재구성하기 위해서 오른손 필기 좌표계 시스템을 이용하여 벡터의 방향적인 성분을 인간의 필기 획의 방향에 알맞게 수정하고, 수정된 세그먼트 벡터의 방향성과 분기 정보를 이용하여 인접한 결합 가능한 세그먼트 벡터를 결합함으로써 문자 인식에 적합한 완전한 획으로 재구성한다. 실험 결과 제안된 방법이 필기체 한글 문자 인식에 적합함을 알 수 있었다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.129-131
• /
• 2006

The performances of neural network systems mainly depend on the kind and the number of input patterns for its training. Hence, the kind of input patterns as well as its number is very important for the character recognition system using back-propagation network. The more input patters are used, the better the system recognizes various characters. However, training is not always successful as the number of input patters increases. Moreover, there exists a limit to consider many input patterns of the recognition system for cursive script characters. In this paper we present a new character recognition system using the back-propagation neural networks. By using an additional neural network, an input pattern generation method is provided for increasing the recognition ratio and a successful training. We firstly introduce the structure of the proposed system. Then, the character recognition system is investigated through some experiments.

• 반도체디스플레이기술학회지
• /
• 제20권3호
• /
• pp.6-10
• /
• 2021

Recognition of characters printed or marked on the PCB components from images captured using cameras is an important task in PCB components inspection systems. Previous optical character recognition (OCR) of PCB components typically consists of two stages: character segmentation and classification of each segmented character. However, character segmentation often fails due to corrupted characters, low image contrast, etc. Thus, OCR without character segmentation is desirable and increasingly used via deep neural networks. Typical implementation based on deep neural nets without character segmentation includes convolutional neural network followed by recurrent neural network (RNN). However, one disadvantage of this approach is slow execution due to RNN layers. LPRNet is a segmentation-free character recognition network with excellent accuracy proved in license plate recognition. LPRNet uses a wide convolution instead of RNN, thus enabling fast inference. In this paper, LPRNet was adapted for recognizing characters printed on PCB components with fast execution and high accuracy. Initial training with synthetic images followed by fine-tuning on real text images yielded accurate recognition. This net can be further optimized on Intel CPU using OpenVINO tool kit. The optimized version of the network can be run in real-time faster than even GPU.