MIRACLE-FI at ImageCLEFphoto 2008: Experiences in merging text-based and content-based retrievals

This paper describes the participation of the MIRACLE consortium at the ImageCLEF Photographic Retrieval task of ImageCLEF 2008. In this is new participation of the group, our first purpose is to evaluate our own tools for text-based retrieval and for content-based retrieval using different similarity metrics and the aggregation OWA operator to fuse the three topic images. From the MIRACLE last year experience, we implemented a new merging module combining the text-based and the content-based information in three different ways: FILTER-N, ENRICH and TEXT-FILTER. The former approaches try to improve the text-based baseline results using the content-based results lists. The last one was used to select the relevant images to the content-based module. No clustering strategies were analyzed. Finally, 41 runs were submitted: 1 for the text-based baseline, 10 content-based runs, and 30 mixed experiments merging text and content-based results. Results in general can be considered nearly acceptable comparing with the best results of other groups. Obtained results from textbased retrieval are better than content-based. Merging both textual and visual retrieval we improve the text-based baseline when applying the ENRICH merging algorithm although visual results are lower than textual ones. From these results we were going to try to improve merged results by clustering methods applied to this image collection

Image Denoising by using Modified SGHP Algorithm

In real time applications, image denoising is a predominant task. This task makes adequate preparation for images looks prominent. But there are several denoising algorithms and every algorithm has its own distinctive attribute based upon different natural images. In this paper, we proposed a perspective that is modified parameter in S-Gradient Histogram Preservation denoising method. S-Gradient Histogram Preservation is a method to compute the structure gradient histogram from the noisy observation by taking different noise standard deviations of different images. The performance of this method is enumerated in terms of peak signal to noise ratio and structural similarity index of a particular image. In this paper, mainly focus on peak signal to noise ratio, structural similarity index, noise estimation and a measure of structure gradient histogram of a given image

Wavelet based Shape Descriptors using Morphology for Texture Classification

The present paper is an extension of our previous paper [1]. In this paper shape descriptors are derived on binary cross diagonal texture matrix (BCDTM) after formation of morphological gradient on the wavelet domain. Morphological gradient is obtained from the difference of dilated and eroded gray level texture. A close relationship can be obtained with contour and texture pattern by evaluating morphological edge information. Morphological operations are simple and they provide topology of the texture, that is the reason the proposed morphological gradient provides abundance of texture and shape information. The proposed Wavelet based morphological gradient binary cross diagonal shape descriptors texture matrix (WMG-BCDSDTM) using wavelets is experimented on wide range of textures for classification purpose. The experimental results indicate a high classification rate

MIRACLE (FI) at ImageCLEFphoto 2009

The Miracle-FI participation at ImageCLEF 2009 photo retrieval task main goal was to improve the merge of content-based and text-based techniques in our experiments. The global system includes our own implemented tool IDRA (InDexing and Retrieving Automatically), and the Valencia University CBIR system. Analyzing both “topics_part1.txt” and “topics_part2.txt” task topics files, we have built different queries files, eliminating the negative sentences with the text from title and clusterTitle or clusterDescription, one query for each cluster (or not) of each topic from 1 to 25 and one for each of the three images of each topic from 26 to 50. In the CBIR system the number of low-level features has been increased from the 68 component used at ImageCLEF 2008 up to 114 components, and in this edition only the Mahalanobis distance has been used in our experiments. Three different merging algorithms were developed in order to fuse together different results lists from visual or textual modules, different textual indexations, or cluster level results into a unique topic level results list. For the five runs submitted we observe that MirFI1, MirFI2 and MifFI3 obtain quite higher precision values than the average ones. Experiment MirFI1, our best run for precision metrics (very similar to MirFI2 and MirFI3), appears in the 16th position in R-Precision classification and in the 19th in MAP one (from a total of 84 submitted experiments). MirFI4 and MirFI5 obtain our best diversity values, appearing in position 11th (over 84) in cluster recall classification, and being the 5th best group from all the 19 participating ones

Image-Based Airborne Sensors: A Combined Approach for Spectral Signatures Classification through Deterministic Simulated Annealing

The increasing technology of high-resolution image airborne sensors, including those on board Unmanned Aerial Vehicles, demands automatic solutions for processing, either on-line or off-line, the huge amountds of image data sensed during the flights. The classification of natural spectral signatures in images is one potential application. The actual tendency in classification is oriented towards the combination of simple classifiers. In this paper we propose a combined strategy based on the Deterministic Simulated Annealing (DSA) framework. The simple classifiers used are the well tested supervised parametric Bayesian estimator and the Fuzzy Clustering. The DSA is an optimization approach, which minimizes an energy function. The main contribution of DSA is its ability to avoid local minima during the optimization process thanks to the annealing scheme. It outperforms simple classifiers used for the combination and some combined strategies, including a scheme based on the fuzzy cognitive maps and an optimization approach based on the Hopfield neural network paradigm

Supervised and unsupervised segmentation of textured images by efficient multi-level pattern classification

This thesis proposes new, efficient methodologies for supervised and unsupervised image segmentation based on texture information. For the supervised case, a technique for pixel classification based on a multi-level strategy that iteratively refines the resulting segmentation is proposed. This strategy utilizes pattern recognition methods based on prototypes (determined by clustering algorithms) and support vector machines. In order to obtain the best performance, an algorithm for automatic parameter selection and methods to reduce the computational cost associated with the segmentation process are also included. For the unsupervised case, the previous methodology is adapted by means of an initial pattern discovery stage, which allows transforming the original unsupervised problem into a supervised one. Several sets of experiments considering a wide variety of images are carried out in order to validate the developed techniques.Esta tesis propone metodologías nuevas y eficientes para segmentar imágenes a partir de información de textura en entornos supervisados y no supervisados. Para el caso supervisado, se propone una técnica basada en una estrategia de clasificación de píxeles multinivel que refina la segmentación resultante de forma iterativa. Dicha estrategia utiliza métodos de reconocimiento de patrones basados en prototipos (determinados mediante algoritmos de agrupamiento) y máquinas de vectores de soporte. Con el objetivo de obtener el mejor rendimiento, se incluyen además un algoritmo para selección automática de parámetros y métodos para reducir el coste computacional asociado al proceso de segmentación. Para el caso no supervisado, se propone una adaptación de la metodología anterior mediante una etapa inicial de descubrimiento de patrones que permite transformar el problema no supervisado en supervisado. Las técnicas desarrolladas en esta tesis se validan mediante diversos experimentos considerando una gran variedad de imágenes

Perceptual texture similarity estimation

This thesis evaluates the ability of computational features to estimate perceptual texture similarity. In the first part of this thesis, we conducted two evaluation experiments on the ability of 51 computational feature sets to estimate perceptual texture similarity using two differ-ent evaluation methods, namely, pair-of-pairs based and retrieval based evaluations. These experiments compared the computational features to two sets of human derived ground-truth data, both of which are higher resolution than those commonly used. The first was obtained by free-grouping and the second by pair-of-pairs experiments. Using these higher resolution data, we found that the feature sets do not perform well when compared to human judgements. Our analysis shows that these computational feature sets either (1) only exploit power spectrum information or (2) only compute higher order statistics (HoS) on, at most, small local neighbourhoods. In other words, they cannot capture aperiodic, long-range spatial relationships. As we hypothesise that these long-range interactions are important for the human perception of texture similarity we carried out two more pair-of-pairs ex-periments, the results of which indicate that long-range interactions do provide humans with important cues for the perception of texture similarity. In the second part of this thesis we develop new texture features that can encode such data. We first examine the importance of three different types of visual information for human perception of texture. Our results show that contours are the most critical type of information for human discrimination of textures. Finally, we report the development of a new set of contour-based features which performed well on the free-grouping data and outperformed the 51 feature sets and another contour type feature set with the pair-of-pairs data

Segmentaçao de imagens baseada em dependencia espacial utilizando campo aleatório de Markov associado com características de texturas

Orientador: Hélio PedriniDissertaçao (mestrado) - Universidade Federal do Paraná, Setor de Ciencias Exatas, Programa de Pós-Graduaçao em Informática. Defesa: Curitiba, 2005Inclui bibliografiaResumo: Uma etapa crítica presente no processo de análise de imagens é a segmentação, responsável por obter informações de alto n'nível sobre as regiões ou objetos contidos na imagem, de modo a facilitar sua interpretação. Contudo, a segmentação ainda é um dos maiores desafios na área de análise de imagens, particularmente quando não se utiliza informações previamente adquiridas sobre a imagem a ser segmentada. Os métodos convencionais de segmentação desconsideram a dependência espacial entre as regiões, o que pode gerar resultados impróprios. Técnicas que consideram a dependência espacial entre as regiões da imagem têm recebido crescente atenção da comunidade científica, pois apresentam uma maior precisão nos resultados obtidos. Embora avanços significativos tenham sido alcançados na segmentação de texturas e de imagens coloridas separadamente, a combinação dessas duas propriedades é considerada como um problema bem mais complexo. Devido a importância dessa etapa no processo de análise de imagens e ao fato de não existirem soluções definitivas para o problema, este trabalho propõe o desenvolvimento de um novo método de segmentação aplicado a imagens texturizadas monocromáticas e coloridas. O método utiliza a formulação Bayesiana para associar a dependência espacial modelada por um campo aleatório de Markov com características de texturas. A segmentação final é obtida por meio da aplicação de t'cênicas de relaxação para minimizar uma função de energia definida a partir da referida associação. Experimentos são efetuados visando avaliar os métodos de análise de texturas, bem como validar a metodologia proposta.Abstract: A critical stage present in the image analysis process is the segmentation, responsible for obtaining high level information about regions or objects in the image, in order to facilitate its interpretation. However, the segmentation is still one of the greatest challenges in the image analysis area, particularly when it does not use information previously acquired on the image to be segmented. Conventional segmentation methods do not consider the spatial dependence between the regions, which can generate improper results. Techniques considering the spatial dependence between the image regions have received increasing attention from the scientific community, because they present a major precision in the obtained results. Although significant advances have been reached in the segmentation of textures and colored images separately, the combination of these two properties is considered a more complex problem. Due to the importance of this stage in the image analysis process and to the fact that does not exist definitive solutions to the problem, this work considers the development of a new segmentation method applied to gray scale and color texture images. The method uses the Bayesian formulation to associate the spatial dependence modeled by a Markov random field with texture features. The final segmentation is obtained by the application of relaxation techniques to minimize an energy function defined by such association. Experiments are performed to evaluate the texture analysis methods, as well as validating the proposal method

Deep Learning in Medical Image Analysis

The accelerating power of deep learning in diagnosing diseases will empower physicians and speed up decision making in clinical environments. Applications of modern medical instruments and digitalization of medical care have generated enormous amounts of medical images in recent years. In this big data arena, new deep learning methods and computational models for efficient data processing, analysis, and modeling of the generated data are crucially important for clinical applications and understanding the underlying biological process. This book presents and highlights novel algorithms, architectures, techniques, and applications of deep learning for medical image analysis