Detecting the presence of large buildings in natural images

This paper addresses the issue of classification of lowlevel features into high-level semantic concepts for the purpose of semantic annotation of consumer photographs. We adopt a multi-scale approach that relies on edge detection to extract an edge orientation-based feature description of the image, and apply an SVM learning technique to infer the presence of a dominant building object in a general purpose collection of digital photographs. The approach exploits prior knowledge on the image context through an assumption that all input images are �outdoor�, i.e. indoor/outdoor classification (the context determination stage) has been performed. The proposed approach is validated on a diverse dataset of 1720 images and its performance compared with that of the MPEG-7 edge histogram descriptor

Improved Texture Feature Extraction and Selection Methods for Image Classification Applications

Classification is an important process in image processing applications, and image texture is the preferable source of information in images classification, especially in the context of real-world applications. However, the output of a typical texture feature descriptor often does not represent a wide range of different texture characteristics. Many research studies have contributed different descriptors to improve the extraction of features from texture. Among the various descriptors, the Local Binary Patterns (LBP) descriptor produces powerful information from texture by simple comparison between a central pixel and its neighbour pixels. In addition, to obtain sufficient information from texture, many research studies have proposed solutions based on combining complementary features together. Although feature-level fusion produces satisfactory results for certain applications, it suffers from an inherent and well-known problem called “the curse of dimensionality’’. Feature selection deals with this problem effectively by reducing the feature dimensions and selecting only the relevant features. However, large feature spaces often make the process of seeking optimum features complicated. This research introduces improved feature extraction methods by adopting a new approach based on new texture descriptors called Local Zone Binary Patterns (LZBP) and Local Multiple Patterns (LMP), which are both based on the LBP descriptor. The produced feature descriptors are combined with other complementary features to yield a unified vector. Furthermore, the combined features are processed by a new hybrid selection approach based on the Artificial Bee Colony and Neighbourhood Rough Set (ABC-NRS) to efficiently reduce the dimensionality of the resulting features from the feature fusion stage. Comprehensive experimental testing and evaluation is carried out for different components of the proposed approach, and the novelty and limitation of the proposed approach have been demonstrated. The results of the evaluation prove the ability of the LZBP and LMP texture descriptors in improving feature extraction compared to the conventional LBP descriptor. In addition, the use of the hybrid ABC-NRS selection method on the proposed combined features is shown to improve the classification performance while achieving the shortest feature length. The overall proposed approach is demonstrated to provide improved texture-based image classification performance compared to previous methods using benchmarks based on outdoor scene images. These research contributions thus represent significant advances in the field of texture-based image classification

Polar Fusion Technique Analysis for Evaluating the Performances of Image Fusion of Thermal and Visual Images for Human Face Recognition

This paper presents a comparative study of two different methods, which are based on fusion and polar transformation of visual and thermal images. Here, investigation is done to handle the challenges of face recognition, which include pose variations, changes in facial expression, partial occlusions, variations in illumination, rotation through different angles, change in scale etc. To overcome these obstacles we have implemented and thoroughly examined two different fusion techniques through rigorous experimentation. In the first method log-polar transformation is applied to the fused images obtained after fusion of visual and thermal images whereas in second method fusion is applied on log-polar transformed individual visual and thermal images. After this step, which is thus obtained in one form or another, Principal Component Analysis (PCA) is applied to reduce dimension of the fused images. Log-polar transformed images are capable of handling complicacies introduced by scaling and rotation. The main objective of employing fusion is to produce a fused image that provides more detailed and reliable information, which is capable to overcome the drawbacks present in the individual visual and thermal face images. Finally, those reduced fused images are classified using a multilayer perceptron neural network. The database used for the experiments conducted here is Object Tracking and Classification Beyond Visible Spectrum (OTCBVS) database benchmark thermal and visual face images. The second method has shown better performance, which is 95.71% (maximum) and on an average 93.81% as correct recognition rate.Comment: Proceedings of IEEE Workshop on Computational Intelligence in Biometrics and Identity Management (IEEE CIBIM 2011), Paris, France, April 11 - 15, 201

Visual and geographical data fusion to classify landmarks in geo-tagged images

High level semantic image recognition and classification is a challenging task and currently is a very active research domain. Computers struggle with the high level task of identifying objects and scenes within digital images accurately in unconstrained environments. In this paper, we present experiments that aim to overcome the limitations of computer vision algorithms by combining them with novel contextual based features to describe geo-tagged imagery. We adopt a machine learning based algorithm with the aim of classifying classes of geographical landmarks within digital images. We use community contributed image sets downloaded from Flickr and provide a thorough investigation, the results of which are presented in an evaluation section