Visualization and Intelligent Systems Laboratory
VISLab

 

 

Contact Information

VISLab
Winston Chung Hall Room 216
University of California, Riverside
900 University Avenue
Riverside, CA 92521-0425


Tel: (951)-827-3954

CRIS
Bourns College of Engineering
UCR
NSF IGERT on Video Bioinformatics

UCR Collaborators:
CSE
ECE
ME
STAT
PSYC
ENTM
BIOL
BPSC
ECON
MATH
BIOENG
MGNT

Other Collaborators:
Keio University

Other Activities:
IEEE Biometrics Workshop 2014
IEEE Biometrics Workshop 2013
Worshop on DVSN 2009
Multibiometrics Book

Webmaster Contact Information:
Alex Shin
wshin@ece.ucr.edu

Last updated: July 1, 2017

 

 

Evolutionary Learning





Feature Fusion of Side Face and Gait for Video-Based Human Identification

Video-based human recognition at a distance remains a challenging problem for the fusion of multimodal biometrics. We present a new approach that utilizes and integrates information from side face and gait at the feature level. The features of face and gait are obtained separately using principal component analysis (PCA) from enhanced side face image (ESFI) and gait energy image (GEI), respectively. Multiple discriminant analysis (MDA) is employed on the concatenated features of face and gait to obtain discriminating synthetic features. The experimental results demonstrate that the synthetic features, encoding both side face and gait information, carry more discriminating power than the individual biometrics features, and the proposed feature level fusion scheme outperforms the match score level and another feature level fusion scheme.

Multiclass Object Recognition Based on Texture Linear Genetic Programming

We present a linear genetic programming approach, that solves simultaneously the region selection and feature extraction tasks, that are applicable to common image recognition problems. The method searches for optimal regions of interest, using texture information as its feature space and classification accuracy as the fitness function. Texture is analyzed based on the gray level cooccurrence matrix and classification is carried out with a SVM committee. Results show effective performance compared with previous results using a standard image database.

Visual Learning by Evolutionary and Coevolutionary Feature Synthesis

We present a novel method for learning complex concepts/hypotheses directly from raw training data. The task addressed here concerns data-driven synthesis of recognition procedures for real-world object recognition. The method uses linear genetic programming to encode potential solutions expressed in terms of elementary operations, and handles the complexity of the learning task by applying cooperative coevolution to decompose the problem automatically at the genotype level. Extensive experimental results show that the approach attains competitive performance for three-dimensional object recognition in real synthetic aperture radar imagery.

On the Number of Subpopulations in Coevolutionary Computation: A Database Application

Among the existing feature selection/synthesis approaches, Coevolutionary Feature Synthesis (CFS) based on Coevolutionary Genetic Programming (CGP) has shown good performance on a variety of applications. In this paper, we propose an MDL-based fitness function to help pick a reasonable number of synthesized features which is equal to the number of subpopulations. It naturally balances the feature transformation complexity and classification performance. Experiments on a real image database show that the new fitness function solves the problem quite well.

Hybrid coevolutionary algorithms vs. SVM algorithms

As a learning method support vector machine is regarded as one of the best classifiers with a strong mathematical foundation. The evolutionary computation has also attracted a lot of attention in pattern recognition and has shown significant performance improvement on a variety of applications. However, there has been no comparison of the two methods. In this paper, first we propose an improvement of a coevolutionary computational classification algorithm, called Improved Coevolutionary Feature Synthesized EM (I-CFS-EM) algorithm. It is a hybrid of coevolutionary genetic programming and EM algorithm applied on partially labeled data. It requires less labeled data and it makes the test in a lower dimension, which speeds up the testing. Then, we provide a comprehensive comparison between SVM with different kernel functions and I-CFS-EM on several real datasets. This comparison shows that I-CFS-EM outperforms SVM in the sense of both the classification performance and the computational efficiency in the testing phase. We also give an intensive analysis of the pros and cons of both approaches.

Fingerprint Matching Using Genetic Algorithms

Fingerprint matching is still a challenging problem for reliable person authentication because of the complex distortions involved in two impressions of the same finger. In this paper, we propose a fingerprint-matching approach based on genetic algorithms (GA), which tries to find the optimal transformation between two different fingerprints. In order to deal with low-quality fingerprint images, which introduce significant occlusion and clutter of minutiae features, we design a fitness function based on the local properties of each triplet of minutiae. The experimental results on National Institute of Standards and Technology fingerprint database, NIST-4, not only show that the proposed approach can achieve good performance even when a large portion of fingerprints in the database are of poor quality, but also show that the proposed approach is better than another approach, which is based on mean-squared error estimation.

Evolutionary Feature Synthesis for Facial Expression Recognition

We propose a novel genetically inspired learning method for facial expression recognition (FER). Our learning method can select visually meaningful features automatically in a genetic programming-based approach that uses Gabor wavelet representation for primitive features and linear/nonlinear operators to synthesize new features. To make use of random nature of a genetic program, we design a multi-agent scheme to boost the performance. We compare the performance of our approach with several approaches in the literature and show that our approach can perform the task of facial expression recognition effectively.

Coevolutionary feature synthesized EM algorithm for image retrieval

In this paper, we propose a unified framework of a novel learning approach, namely Coevolutionary Feature Synthesized Expectation-Maximization (CFSEM), to achieve satisfactory learning in spite of these difficulties. The CFS-EM is a hybrid of coevolutionary genetic programming (CGP) and EM algorithm. The advantages of CFS-EM are: 1) it synthesizes low-dimensional features based on CGP algorithm, which yields near optimal nonlinear transformation and classification precision comparable to kernel methods such as the support vector machine (SVM); 2) the explicitness of feature transformation is especially suitable for image retrieval because the images can be searched in the synthesized low-dimensional space, while kernel-based methods have to make classification computation in the original high-dimensional space; 3) the unlabeled data can be boosted with the help of the class distribution learning using CGP feature synthesis approach. Experimental results show that CFS-EM outperforms pure EM and CGP alone, and is comparable to SVM in the sense of classification. It is computationally more efficient than SVM in query phase. Moreover, it has a high likelihood that it will jump out of a local maximum to provide near optimal results and a better estimation of parameters.

Evolutionary Feature Synthesis for Object Recognition

We propose a coevolutionary genetic programming (CGP) approach to learn composite features for object recognition. The motivation for using CGP is to overcome the limitations of human experts who consider only a small number of conventional combinations of primitive features during synthesis. CGP, on the other hand, can try a very large number of unconventional combinations and these unconventional combinations yield exceptionally good results in some cases. The comparison with other classical classification algorithms is favourable to the CGP-based approach proposed in our research.

Visual learning by coevolutionary feature synthesis

In this paper, a novel genetically inspired visual learning method is proposed. Given the training raster images, this general approach induces a sophisticated feature-based recognition system. It employs the paradigm of cooperative coevolution to handle the computational difficulty of this task. To represent the feature extraction agents, the linear genetic programming is used. The paper describes the learning algorithm and provides a firm rationale for its design. Different architectures of recognition systems are considered that employ the proposed feature synthesis method. An extensive experimental evaluation on the demanding real-world task of object recognition in synthetic aperture radar (SAR) imagery shows the ability of the proposed approach to attain high recognition performance in different operating conditions.

Object Detection via Feature Synthesis Using MDL-Based Genetic Programming

We use genetic programming (GP) to synthesize composite operators and composite features from combinations of primitive operations and primitive features for object detection. The motivation for using GP is to overcome the human experts' limitations of focusing only on conventional combinations of primitive image processing operations in the feature synthesis. GP attempts many unconventional combinations that in some cases yield exceptionally good results. Our experiments, which are performed on selected training regions of a training image to reduce the training time, show that compared to normal GP, our GP algorithm finds effective composite operators more quickly and the learned composite operators can be applied to the whole training image and other similar testing images.

MDL-based Genetic Programming for Object Detection

Genetic programming (GP) is applied to synthesize composite operators from primitive operators and primitive features for object detection. To improve the efficiency of GP, smart crossover, smart mutation and a public library are proposed to identify and keep the effective components of composite operators. To prevent code bloat and avoid severe restriction on the GP search, a MDL-based fitness function is designed to incorporate the size of composite operator into the fitness evaluation process. The experiments with real synthetic aperture radar (SAR) images show that compared to normal GP, GP algorithm proposed here finds effective composite operators more quickly.

Fingerprint Classification Based on Learned Features

We present a fingerprint classification approach based on a novel feature-learning algorithm. Unlike current research for fingerprint classification that generally uses well defined meaningful features, our approach is based on Genetic Programming (GP), which learns to discover composite operators and features that are evolved from combinations of primitive image processing operations. Our experimental results show that our approach can find good composite operators to effectively extract useful features.

Evolutionary feature synthesis for image databases

In this paper, we investigate the effectiveness of coevolutionary genetic programming (CGP) in synthesizing feature vectors for image databases from traditional features that are commonly used. The transformation for feature dimensionality reduction by CGP has two unique characteristics for image retrieval: 1) nonlinearlity: CGP does not assume any class distribution in the original visual feature space; 2) explicitness: unlike kernel trick, CGP yields explicit transformation for dimensionality reduction so that the images can be searched in the low-dimensional feature space. The experimental results on multiple databases show that (a) CGP approach has distinct advantage over the linear transformation approach of Multiple Discriminant Analysis (MDA) in the sense of the discrimination ability of the low-dimensional features, and (b) the classification performance using the features synthesized by our CGP approach is comparable to or even superior to that of support vector machine (SVM) approach using the original visual features.

Object detection in multimodal images using genetic programming

In this paper, we learn to discover composite operators and features that are synthesized from combinations of primitive image processing operations for object detection. Our approach is based on genetic programming (GP). The motivation for using GP-based learning is that we hope to automate the design of object detection system by automatically synthesizing object detection procedures from primitive operations and primitive features. The human expert, limited by experience, knowledge and time, can only try a very small number of conventional combinations. Genetic programming, on the other hand, attempts many unconventional combinations that may never be imagined by human experts. In some cases, these unconventional combinations yield exceptionally good results.

Cooperative coevolution fusion for moving object detection

In this paper we introduce a novel sensor fusion algorithm based on the cooperative coevolutionary paradigm. We develop a multisensor robust moving object detection system that can operate under a variety of illumination and environmental conditions. Our experiments indicate that this evolutionary paradigm is well suited as a sensor fusion model and can be extended to different sensing modalities.

Synthesizing Feature Agents Using Evolutionary Computation

Genetic programming (GP) with smart crossover and smart mutation is proposed in our research to discover integrated feature agents that are evolved from combinations of primitive image processing operations to extract regions-of-interest (ROIs) in remotely sensed images. Smart crossover and smart mutation identify and keep the effective components of integrated operators called "agents" and significantly improve the efficiency of GP. Our experimental results show that compared to normal GP, our GP algorithm with smart crossover and smart mutation can find good agents more quickly during training to effectively extract the regions-of-interest and the learned agents can be applied to extract ROIs in other similar images.

Learning integrated perception-based speed control

Advances in the area of autonomous mobile robotics have allowed robots to explore vast and often unknown terrains. This paper presents a particular form of autonomy that allows a robot to autonomously control its speed, based on perception, while traveling on unknown terrain. The robot is equipped with an onboard camera and a 3-axis accelerometer. The method begins by classifying a query image of the terrain immediately before the robot. Classification is based on the Gabor wavelet features. In learning the speed, a genetic algorithm is used to map the Gabor texture features to approximate speed that minimizes changes in accelerations along the three axes from their nominal values. Learning is performed continuously. Experiments are done in real time.

Functional Template-based SAR Image Segmentation

We present an approach to automatic image segmentation, in which user selected sets of examples and counter-examples supply information about the specific segmentation problem. In our approach, image segmentation is guided by a genetic algorithm which learns the appropriate subset and spatial combination of a collection of discriminating functions, associated with image features. The genetic algorithm encodes discriminating functions into a functional template representation, which can be applied to the input image to produce a candidate segmentation.

Learning composite features for object recognition

Features represent the characteristics of objects and selecting or synthesizing effective composite features are the key factors to the performance of object recognition. In this paper, we propose a co-evolutionary genetic programming (CGP) approach to learn composite features for object recognition. The motivation for using CGP is to overcome the limitations of human experts who consider only a small number of conventional combinations of primitive features during synthesis. On the other hand, CGP can try a very large number of unconventional combinations and these unconventional combinations may yield exceptionally good results in some cases. Our experimental results with real synthetic aperture radar (SAR) images show that CGP can learn good composite features. We show results to distinguish objects from clutter and to distinguish objects that belong to several classes.

Coevolutionary computation for synthesis of recognition systems

This paper introduces a novel visual learning method that involves cooperative coevolution and linear genetic programming. Given exclusively training images, the evolutionary learning algorithm induces a set of sophisticated feature extraction agents represented in a procedural way. The proposed method incorporates only general vision-related background knowledge and does not require any task-specific information. The paper describes the learning algorithm, provides a firm rationale for its design, and proves its competitiveness with the human-designed recognition systems in an extensive experimental evaluation, on the demanding real-world task of object recognition in synthetic aperture radar (SAR) imagery.

Learning Composite Operators for Object Detection

We have learned through this research to discover composite operators and features that are evolved from combinations of primitive image processing operations to extract regions-of-interest (ROIs) in images. Our approach is based on genetic programming (GP). The motivation for using GP is that there are a great many ways of combining these primitive operations and the human expert, limited by experience, knowledge and time, can only try a very small number of conventional ways of combination. Genetic programming, on the other hand, attempts many unconventional ways of combination that may never be imagined by human experts. In some cases, these unconventional combinations yield exceptionally good results. Our experimental results show that GP can find good composite operators, that consist of primitive operators designed by us, to effectively extract the regions of interest in images and the learned composite operators can be applied to extract ROIs in other similar images.

Genetic Algorithm Based Feature Selection for Target Detection in SAR Images

A genetic algorithm (GA) approach is presented to select a set of features to discriminate the targets from the natural clutter false alarms in SAR images. A new fitness function based on minimum description length principle (MDLP) is proposed to drive GA and it is compared with three other fitness functions. Experimental results show that the new fitness function outperforms the other three fitness functions and the GA driven by it selected a good subset of features to discriminate the targets from clutters effectively.

Learning feature agents for extracting terrain regions in remotely sensed images

In this paper, we apply genetic programming (GP) with smart crossover and smart mutation to discover integrated feature agents that are evolved from combinations of primitive image processing operations to extract regions-of-interest (ROIs) in remotely sensed images. The motivation for using genetic programming is to overcome the limitations of human experts, since GP attempts many unconventional ways of combination, in some cases, these unconventional combinations yield exceptionally good results. Smart crossover and smart mutation identify and keep the effective components of integrated operators called "agents" and significantly improve the efficiency of GP. Our experimental results show that compared to normal GP, our GP algorithm with smart crossover and smart mutation can find good agents more quickly during training to effectively extract the regions-of-interest and the learned agents can be applied to extract ROIs in other similar images.

Discovering operators and features for object detection

In this paper, we learn to discover composite operators and features that are evolved from combinations of primitive image processing operations to extract regions-of-interest (ROls) in images. Our approach is based on genetic programming (GP). The motivation for using GP is that there are a great many ways of combining these primitive operations and the human expert, limited by experience, knowledge and time. can only try a very small number of conventional ways of combination. Genetic programming, on the other hand, attempts many unconventional ways of combination that may never be imagined by human experts. In some cases, these unconventional combinations yield exceptionally good results. Our experimental results show that GP can find good composite operators to effectively extract the regions of interest in an image and the. learned composite operators can be applied to extract ROls in other similar images.

Coevolutionary construction of features by transformation of representation in machine learning

The main objective of this paper is to study the usefulness of cooperative coevolutionary algorithms (CCA) for improving the performance of classification of machine learning (ML) classifiers, in particular those following the symbolic paradigm. For this purpose, we present a genetic programming (GP) -based coevolutionary feature construction procedure. In the experimental part, we confront the coevolutionary methodology with difficult real-world ML task with unknown internal structure and complex interrelationships between solution subcomponents (features), as opposed to artificial problems considered usually in the literature.

Learning based interactive image segmentation

In this paper, we present an approach, to image segmentation in which user selected sets of examples and counter-examples supply information about the specific segmentation problem. Image segmentation is guided by a genetic algorithm, which learns the appropriate subset and spatial combination of a collection of discriminating functions, associated with image features. The genetic algorithm encodes discriminating functions into a functional template representation, which can be applied to the input image to produce a candidate segmentation. The quality of each segmentation is evaluated within the genetic algorithm, by a comparison of two physics-based techniques for region growing and edge detection. Experimental results on real SAR imagery demonstrate that evolved segmentations are consistently better than segmentations derived from the Bayesian best single feature.

Adaptive Image Segmentation Using Genetic and Hybrid Search Methods

One of the fundamental weaknesses of computer vision systems used in practical applications was their inability to adapt the segmentation process as real-world changes occurred in the image. Presented is the first closed loop image segmentation system which incorporated a genetic algorithm to adapt the segmentation process to changes in image characteristics caused by variable environmental conditions such as time of day, time of year, clouds, etc. The segmentation problem was formulated as an optimization problem and the genetic algorithm efficiently searched the hyperspace of segmentation parameter combinations to determine the parameter set which maximized the segmentation quality criteria. The goals of the adaptive image segmentation system were to provide continuous adaptation to normal environmental variations, to exhibit learning capabilities, and to provide robust performance when interacting with a dynamic environment. Also presented are experimental results which demonstrated learning and the ability to adapt the segmentation performance in outdoor color imagery.

Adaptive Image Segmentation Using a Genetic Algorithm

One of the fundamental weaknesses of computer vision systems used in practical applications was their inability to adapt the segmentation process as real-world changes occurred in the image. Presented is the first closed loop image segmentation system which incorporated a genetic algorithm to adapt the segmentation process to changes in image characteristics caused by variable environmental conditions such as time of day, time of year, clouds, etc. The segmentation problem was formulated as an optimization problem and the genetic algorithm efficiently searched the hyperspace of segmentation parameter combinations to determine the parameter set which maximized the segmentation quality criteria. The goals of the adaptive image segmentation system were to provide continuous adaptation to normal environmental variations, to exhibit learning capabilities, and to provide robust performance when interacting with a dynamic environment. Also presented are experimental results which demonstrated learning and the ability to adapt the segmentation performance in outdoor color imagery.