2,714 research outputs found

    Cluster Coding With Modified Flood Fill Algorithm For Texture Segmentation[QA1].

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    Tekstur merujuk kepada sifat yang menggambarkan permukaan atau struktur sesuatu objek dan ditakrifkan sebagai terdiri daripada unsur-unsur yang saling berhubung. Fokus utama dalam kajian ini ialah pensegmenan tekstur dalam imej digit dua dimensi. Texture refers to properties that represent the surface or structure of an object and is defined as something consisting of mutually related elements. The main focus in this study is to do texture segmentation in two dimensional (2D) digital images

    Evaluation of Statistical Features for Medical Image Retrieval

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    In this paper we present a complete system allowing the classification of medical images in order to detect possible diseases present in them. The proposed method is developed in two distinct stages: calculation of descriptors and their classification. In the first stage we compute a vector of thirty-three statistical features: seven are related to statistics of the first level order, fifteen to that of second level where thirteen are calculated by means of co-occurrence matrices and two with absolute gradient; the last thirteen finally are calculated using run-length matrices. In the second phase, using the descriptors already calculated, there is the actual image classification. Naive Bayes, RBF, Support VectorMa- chine, K-Nearest Neighbor, Random Forest and Random Tree classifiers are used. The results obtained from the proposed system show that the analysis carried out both on textured and on medical images lead to have a high accuracy

    Multi texture analysis of colorectal cancer continuum using multispectral imagery

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    Purpose This paper proposes to characterize the continuum of colorectal cancer (CRC) using multiple texture features extracted from multispectral optical microscopy images. Three types of pathological tissues (PT) are considered: benign hyperplasia, intraepithelial neoplasia and carcinoma. Materials and Methods In the proposed approach, the region of interest containing PT is first extracted from multispectral images using active contour segmentation. This region is then encoded using texture features based on the Laplacian-of-Gaussian (LoG) filter, discrete wavelets (DW) and gray level co-occurrence matrices (GLCM). To assess the significance of textural differences between PT types, a statistical analysis based on the Kruskal-Wallis test is performed. The usefulness of texture features is then evaluated quantitatively in terms of their ability to predict PT types using various classifier models. Results Preliminary results show significant texture differences between PT types, for all texture features (p-value < 0.01). Individually, GLCM texture features outperform LoG and DW features in terms of PT type prediction. However, a higher performance can be achieved by combining all texture features, resulting in a mean classification accuracy of 98.92%, sensitivity of 98.12%, and specificity of 99.67%. Conclusions These results demonstrate the efficiency and effectiveness of combining multiple texture features for characterizing the continuum of CRC and discriminating between pathological tissues in multispectral images

    An automated pattern recognition system for classifying indirect immunofluorescence images for HEp-2 cells and specimens

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    AbstractImmunofluorescence antinuclear antibody tests are important for diagnosis and management of autoimmune conditions; a key step that would benefit from reliable automation is the recognition of subcellular patterns suggestive of different diseases. We present a system to recognize such patterns, at cellular and specimen levels, in images of HEp-2 cells. Ensembles of SVMs were trained to classify cells into six classes based on sparse encoding of texture features with cell pyramids, capturing spatial, multi-scale structure. A similar approach was used to classify specimens into seven classes. Software implementations were submitted to an international contest hosted by ICPR 2014 (Performance Evaluation of Indirect Immunofluorescence Image Analysis Systems). Mean class accuracies obtained on heldout test data sets were 87.1% and 88.5% for cell and specimen classification respectively. These were the highest achieved in the competition, suggesting that our methods are state-of-the-art. We provide detailed descriptions and extensive experiments with various features and encoding methods

    Assessment of multi-temporal, multi-sensor radar and ancillary spatial data for grasslands monitoring in Ireland using machine learning approaches

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    Accurate inventories of grasslands are important for studies of carbon dynamics, biodiversity conservation and agricultural management. For regions with persistent cloud cover the use of multi-temporal synthetic aperture radar (SAR) data provides an attractive solution for generating up-to-date inventories of grasslands. This is even more appealing considering the data that will be available from upcoming missions such as Sentinel-1 and ALOS-2. In this study, the performance of three machine learning algorithms; Random Forests (RF), Support Vector Machines (SVM) and the relatively underused Extremely Randomised Trees (ERT) is evaluated for discriminating between grassland types over two large heterogeneous areas of Ireland using multi-temporal, multi-sensor radar and ancillary spatial datasets. A detailed accuracy assessment shows the efficacy of the three algorithms to classify different types of grasslands. Overall accuracies ≥ 88.7% (with kappa coefficient of 0.87) were achieved for the single frequency classifications and maximum accuracies of 97.9% (kappa coefficient of 0.98) for the combined frequency classifications. For most datasets, the ERT classifier outperforms SVM and RF

    Optimization of 3D texture analysis of MR cartilage images for prediction of knee osteoarthritis

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    Abstract. This thesis attempted to optimize a novel GLCM-based 3D Texture Analysis software in terms of its input parameters in order to maximize the early prediction of knee osteoarthritis from 3D DESS MR images. 20 subjects (10 control subjects; 10 progressor subjects) containing image data from baseline and from a 36-month-follow-up were extracted from the Osteoarthritis Initiative database and used as the study dataset. Multiple sets of 3D Texture Analysis were conducted incorporating 22 static and dynamic grey level quantization schemes, 6 bin quantization schemes and 4 offset settings. Cliff’s delta was calculated to measure the effect size between the patient cohorts. Multilayer perceptron, Naïve Bayes and Support Vector Machines were implemented to classify the patients into their respective cohorts and estimate the robustness of the 3D Texture Analysis outputs. The predictions were done using only the baseline data, where all patients showed no signs of osteoarthritis. Maximum achieved robustness was 87%. The 3D Texture Analysis was found to have a high potential for the early prediction of knee osteoarthritis based on the GLCM features and the results outlined the importance of the software’s input parameters
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