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Ching Y. Suen

Bio: Ching Y. Suen is an academic researcher from Concordia University. The author has contributed to research in topics: Handwriting recognition & Feature extraction. The author has an hindex of 65, co-authored 511 publications receiving 23594 citations. Previous affiliations of Ching Y. Suen include École de technologie supérieure & Concordia University Wisconsin.


Papers
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Journal ArticleDOI
TL;DR: In this article, an experiment was conducted to investigate the discrimination of six vowel sounds of 10 msec duration using both phonetically trained (PT) and untrained (UPT) Ss.
Abstract: An experiment was conducted to investigate the discrimination of six vowel sounds of 10 msec duration. Vowels of equal pitch and intensity level were generated by computer. Both phonetically trained (PT) and untrained (UPT) Ss were used. Rapid learning took place, and the PT Ss showed much better discrimination than the UPT Ss. Confusion matrices of the last four learning blocks indicated that /i/ and /u/ sounded very much alike when they were short. The pattern of the test scores was discussed with reference to pure tone perception.

17 citations

Journal ArticleDOI
TL;DR: In this article, a database of more than 100, 000 alphanumeric patterns was assembled, consisting of 174 models of the alphabetic characters written by both left-handed and right-handed subjects.
Abstract: Since handwritten characters vary in shape and writing-stroke sequence, it is desirable to develop a standard set of characters that are of high quality, so that not only are they easy to write, but they are also most suitable for machine recognition. A database of more than 100 000 alphanumeric patterns was assembled. It consisted of 174 models of the alphanumeric characters written by both left-handed and right-handed subjects. Based on frequency density and distance measurements, a nietric called the dispersion factor was computed to rank the various models. The principle of the metric is discussed, and results are given indicating the high quality models of the alphanumerics.

17 citations

Journal ArticleDOI
01 Jun 1989
TL;DR: In this paper, four modifications of ZR descriptors are proposed based on the step signature, smoothed signature, linearized smoothed signatures, and the curvature function, respectively, which are shown to be invariant under rotations, translations, changes in size, mirror reflections, and shifts in the starting point.
Abstract: Two kinds of Fourier shape descriptors (FDs) are considered in this article: ZR (defined by Zahn and Roskies) and G (defined by Granlund). The first section of this article studies ZR descriptors. Four modifications of ZR descriptors are proposed. These new descriptors are based on the step signature, smoothed signature, linearized smoothed signature, and the curvature function, respectively. The amplitudes of FDs are shown to be invariant under rotations, translations, changes in size, mirror reflections, and shifts in the starting point. In all cases the reconstruction accuracy in terms of the number of FDs is studied, resulting in approximation error bounds. An efficient reconstruction formula based on the composite rectangle integration method is proposed. This method also provides polygonal approximation for arbitrary contours. In the second section of this article, the theoretical results are illustrated with examples and verified in numerical experiments involving digitized patterns. In the same experiments the performances of ZR and G descriptors are compared.

17 citations

Proceedings ArticleDOI
23 Aug 2010
TL;DR: A novel word spotting system for Urdu words within handwritten text lines is proposed based on the outputs from the Urdu word recognition system and the image’s global features were applied to achieve a promising result.
Abstract: We propose a novel word spotting system for Urdu words within handwritten text lines. Spatial information of diacritics is integrated to the detection of the main connected components in candidate words generation. An Urdu word recognition system is effectively designed and applied to classify the candidate words. In this word recognition system, compound features and SVM were adapted. The verification/rejection process was based on the outputs from the Urdu word recognition system and the image’s global features were applied to achieve a promising result. As a result, a high 92.11% correct segmentation rate, a 50.75% word spotting precision rate were achieved while maintaining a 70.1% recall on CENPARMI’s Urdu Database.

17 citations

Proceedings ArticleDOI
23 Aug 2010
TL;DR: Error-correcting output coding to the outputs of a convolutional neural network provides the neural network with more reliable decision rules and enables it to perform more accurate and reliable detection and recognition of targets.
Abstract: This paper views target detection and pattern recognition as a kind of communications problem and applies error-correcting coding to the outputs of a convolutional neural network to improve the accuracy and reliability of detection and recognition of targets. The outputs of the convolutional neural network are designed according to codewords with maximum Hamming distances. The effects of the codewords on the performance of the convolutional neural network in target detection and recognition are then investigated. Images of hand-written digits and printed English letters and symbols are used in the experiments. Results show that error-correcting output coding provides the neural network with more reliable decision rules and enables it to perform more accurate and reliable detection and recognition of targets. Moreover, our error-correcting output coding can reduce the number of neurons required, which is highly desirable in efficient implementations.

17 citations


Cited by
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Journal ArticleDOI
01 Jan 1998
TL;DR: In this article, a graph transformer network (GTN) is proposed for handwritten character recognition, which can be used to synthesize a complex decision surface that can classify high-dimensional patterns, such as handwritten characters.
Abstract: Multilayer neural networks trained with the back-propagation algorithm constitute the best example of a successful gradient based learning technique. Given an appropriate network architecture, gradient-based learning algorithms can be used to synthesize a complex decision surface that can classify high-dimensional patterns, such as handwritten characters, with minimal preprocessing. This paper reviews various methods applied to handwritten character recognition and compares them on a standard handwritten digit recognition task. Convolutional neural networks, which are specifically designed to deal with the variability of 2D shapes, are shown to outperform all other techniques. Real-life document recognition systems are composed of multiple modules including field extraction, segmentation recognition, and language modeling. A new learning paradigm, called graph transformer networks (GTN), allows such multimodule systems to be trained globally using gradient-based methods so as to minimize an overall performance measure. Two systems for online handwriting recognition are described. Experiments demonstrate the advantage of global training, and the flexibility of graph transformer networks. A graph transformer network for reading a bank cheque is also described. It uses convolutional neural network character recognizers combined with global training techniques to provide record accuracy on business and personal cheques. It is deployed commercially and reads several million cheques per day.

42,067 citations

Journal ArticleDOI
TL;DR: Machine learning addresses many of the same research questions as the fields of statistics, data mining, and psychology, but with differences of emphasis.
Abstract: Machine Learning is the study of methods for programming computers to learn. Computers are applied to a wide range of tasks, and for most of these it is relatively easy for programmers to design and implement the necessary software. However, there are many tasks for which this is difficult or impossible. These can be divided into four general categories. First, there are problems for which there exist no human experts. For example, in modern automated manufacturing facilities, there is a need to predict machine failures before they occur by analyzing sensor readings. Because the machines are new, there are no human experts who can be interviewed by a programmer to provide the knowledge necessary to build a computer system. A machine learning system can study recorded data and subsequent machine failures and learn prediction rules. Second, there are problems where human experts exist, but where they are unable to explain their expertise. This is the case in many perceptual tasks, such as speech recognition, hand-writing recognition, and natural language understanding. Virtually all humans exhibit expert-level abilities on these tasks, but none of them can describe the detailed steps that they follow as they perform them. Fortunately, humans can provide machines with examples of the inputs and correct outputs for these tasks, so machine learning algorithms can learn to map the inputs to the outputs. Third, there are problems where phenomena are changing rapidly. In finance, for example, people would like to predict the future behavior of the stock market, of consumer purchases, or of exchange rates. These behaviors change frequently, so that even if a programmer could construct a good predictive computer program, it would need to be rewritten frequently. A learning program can relieve the programmer of this burden by constantly modifying and tuning a set of learned prediction rules. Fourth, there are applications that need to be customized for each computer user separately. Consider, for example, a program to filter unwanted electronic mail messages. Different users will need different filters. It is unreasonable to expect each user to program his or her own rules, and it is infeasible to provide every user with a software engineer to keep the rules up-to-date. A machine learning system can learn which mail messages the user rejects and maintain the filtering rules automatically. Machine learning addresses many of the same research questions as the fields of statistics, data mining, and psychology, but with differences of emphasis. Statistics focuses on understanding the phenomena that have generated the data, often with the goal of testing different hypotheses about those phenomena. Data mining seeks to find patterns in the data that are understandable by people. Psychological studies of human learning aspire to understand the mechanisms underlying the various learning behaviors exhibited by people (concept learning, skill acquisition, strategy change, etc.).

13,246 citations

Journal ArticleDOI
TL;DR: The objective of this review paper is to summarize and compare some of the well-known methods used in various stages of a pattern recognition system and identify research topics and applications which are at the forefront of this exciting and challenging field.
Abstract: The primary goal of pattern recognition is supervised or unsupervised classification. Among the various frameworks in which pattern recognition has been traditionally formulated, the statistical approach has been most intensively studied and used in practice. More recently, neural network techniques and methods imported from statistical learning theory have been receiving increasing attention. The design of a recognition system requires careful attention to the following issues: definition of pattern classes, sensing environment, pattern representation, feature extraction and selection, cluster analysis, classifier design and learning, selection of training and test samples, and performance evaluation. In spite of almost 50 years of research and development in this field, the general problem of recognizing complex patterns with arbitrary orientation, location, and scale remains unsolved. New and emerging applications, such as data mining, web searching, retrieval of multimedia data, face recognition, and cursive handwriting recognition, require robust and efficient pattern recognition techniques. The objective of this review paper is to summarize and compare some of the well-known methods used in various stages of a pattern recognition system and identify research topics and applications which are at the forefront of this exciting and challenging field.

6,527 citations

Journal ArticleDOI
TL;DR: A common theoretical framework for combining classifiers which use distinct pattern representations is developed and it is shown that many existing schemes can be considered as special cases of compound classification where all the pattern representations are used jointly to make a decision.
Abstract: We develop a common theoretical framework for combining classifiers which use distinct pattern representations and show that many existing schemes can be considered as special cases of compound classification where all the pattern representations are used jointly to make a decision. An experimental comparison of various classifier combination schemes demonstrates that the combination rule developed under the most restrictive assumptions-the sum rule-outperforms other classifier combinations schemes. A sensitivity analysis of the various schemes to estimation errors is carried out to show that this finding can be justified theoretically.

5,670 citations

Book
01 Jan 1996
TL;DR: Professor Ripley brings together two crucial ideas in pattern recognition; statistical methods and machine learning via neural networks in this self-contained account.
Abstract: From the Publisher: Pattern recognition has long been studied in relation to many different (and mainly unrelated) applications, such as remote sensing, computer vision, space research, and medical imaging. In this book Professor Ripley brings together two crucial ideas in pattern recognition; statistical methods and machine learning via neural networks. Unifying principles are brought to the fore, and the author gives an overview of the state of the subject. Many examples are included to illustrate real problems in pattern recognition and how to overcome them.This is a self-contained account, ideal both as an introduction for non-specialists readers, and also as a handbook for the more expert reader.

5,632 citations