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EN
In this paper, a new method for automatic detection of microcalcifications in digitized mammograms is proposed. Based on mathematical morphology theory to deal with the problem of low contrast between microcalcifications and their surrounding pixels, it uses various structuring elements of different sizes to reduce the sensibility to microcalcification diversity sizes. The obtained morphological results are converted to a suspicion map based on an image quality assessment metric called structural similarity index (SSIM). This continuous map is, then, locally analyzed using superpixels to automatically estimate threshold values and finally detect potential microcalcification areas. The proposed method was evaluated using the publiclyavailable INBreast dataset. Experimental results show the benefits gained in terms of improving microcalcification detection performances compared to state-of-the-art methods.
EN
In this paper methods and their examination results for automatic segmentation and parameterization of vessels based on spectral domain optical coherence tomography (SD-OCT) of the retina are presented. We present three strategies for morphologic image processing of a fundus image reconstructed from OCT scans. A specificity of initial image processing for fundus reconstruction is analysed. Then, the parameterization step is performed based on the vessels segmented with the proposed algorithm. The influence of various methods on the vessel segmentation and fully automatic vessel measurement is analysed. Experiments were carried out with a set of 3D OCT scans obtained from 24 eyes (12 healthy volunteers) with the use of an Avanti RTvue OCT device. The results of automatic vessel segmentation were numerically compared with those prepared manually by the medical doctor experts.
EN
Urbanization has a far-reaching impact on the environment, economy, politi-cal and social processes. Therefore, understanding the spatial distribution and evolution ofhuman settlements is a key element in planning strategies that ensure the sustainable de-velopment of urban and rural settlements. Accordingly, it is very important to map humansettlements and to monitor the development of cities and villages. Therefore, the problem ofsettlements has found its reflection in the creation of global databases of urban areas. Globalsettlement data have extraordinary value. These data allow us to carry out the quantitativeand qualitative analyses as well as to compare the settlement network at a regional, nationaland global scale. However, the possibility of conducting both spatial and attribute analysesof these data would be even more valuable. The article describes how to prepare raster dataso that they can be implemented into a vector database. It answers the questions whetherit is possible to combine these data with databases available in Poland and what benefits itbrings. It presents the methods of data generalization and the optimization of time and diskspace. As a result of the study, two vector databases with GUF data were developed. Thefirst database resolution is similar to the original (~12 m resolution) database, the seconddatabase contains less detailed (~20 m resolution) data, generalized using mathematicalmorphology. Both databases have been enriched with descriptive data obtained from theNational Geodetic and Cartographic Resource.
PL
W pracy przedstawiono przykłady użycia transformacji TOP-HAT do przetwarzania sekwencji termogramów. Zaprezentowano podstawy teoretyczne morfologii matematycznej w zastosowaniu do przetwarzania obrazów termalnych. Celem przetwarzania była korekcja niejednorodności nagrzania powierzchni próbki badanego materiału zawierającej defekty o różnych głębokościach. Do określenia rozmiaru i kształtu elementu strukturalnego użytego w transformacji TOP-HAT zaproponowano kryterium oparte na pojęciu odległości pomiędzy obiektami w wielowymiarowej przestrzeni cech. W wyniku badań stwierdzono, że największą wrażliwość na wielkość elementu strukturalnego wykazuje odległość euklidesowa.
EN
In defect detection techniques applied in the active thermography, the learning machine algorithms are increasingly used. During experiments the surface of material sample is heated and the thermal response is obtained as an transient temperature field which is recorded in the form of a sequence of thermal images. In this work, the use of TOP-HAT transformation to the thermal images processing were presented. The purpose of the processing was the correction of the uneven heating of defective material sample. In the sample used in the research, the aerial defects at different depths were artificially prepared. In paper, it was proposed a novel method for determination of the structural element size and shape, used in the TOP-HAT transformation of a thermal images sequence. This method is based on the notion of distance between the objects existing in the multidimensional feature space. In this work the exemplary results of the processing of thermal images sequence with the TOP-HAT transform were presented. It was found, that the most sensitivity to size of the structural element used in the TOP-HAT transform procedure, is the Euclidean distance.
EN
The article presents studies on the impact of the source image type on the efficacy of image texture analysis in the terms of distinguishing classes of land use or land cover (LULC). Single gray-scale images are usually the inputs for this type of operation, however their selection is not unambiguous, especially in the case of multispectral images. Two very high resolution satellite images were used in the study: Pleiades (GSD: 2 m) and QuickBird (2.4 m). Five different input images were tested: the original near-infrared and red bands, the images of the first two main components, and the image of the normalised difference vegetation index - NDVI. Five LULC classes were compared to each other: bare soil, low vegetation, deciduous forests, coniferous forests and built-up areas. Granulometric analysis, as the one of the high efficient methods of texture analysis, was used for the test. Research results have shown that the choice of source image for this kind of processing can be very important for the efficacy of distinguishing between different LULC classes. NDVI images, and also the near infrared band and the first principal component were found most useful.
PL
Artykuł przedstawia badania dotyczące wpływu typu obrazu źródłowego na skuteczność analizy teksturowej obrazu z punktu widzenia wyodrębniania klas użytkowania lub pokrycia terenu (LULC). Tego typu operacjom poddawane są zazwyczaj pojedyncze obrazy w skali szarości, jednak ich wybór nie jest jednoznaczny, zwłaszcza w przypadku obrazów wielospektralnych. W badaniach wykorzystano dwa obrazy satelitarne o bardzo wysokiej rozdzielczości: Pleiades (GSD: 2 m) oraz QuickBird (2,4 m). Testowano pięć różnych obrazów wejściowych: oryginalne kanały bliskiej podczerwieni oraz czerwieni, obrazy dwóch pierwszych składowych głównych oraz obraz wskaźnika NDVI. Porównano wzajemnie pięć klas użytkowania lub pokrycia terenu: odkrytą glebę, niską roślinność, lasy liściaste, lasy iglaste oraz tereny zabudowane. Jako narzędzie testów wybrano analizę granulometryczną, jedną z metod analizy teksturowej o wysokiej skuteczności. Wyniki badań pokazały, że wybór obrazu źródłowego do przetworzeń może mieć bardzo duże znaczenie przy rozróżnianiu różnych klas użytkowania lub pokrycia terenu. Największą przydatnością cechowały się obrazy NDVI oraz kanału bliskiej podczerwieni i pierwszej składowej głównej.
PL
Celem pracy jest próba formalizacji i implementacji zasad generalizacji osadnictwa oraz sieci dróg bazy danych obiektów topograficznych w skali 1:10 000 do skali 1:50 000 zgodnie z obowiązującymi przepisami. Implementację opracowanej kartograficznej bazy wiedzy przeprowadzono w środowisku QGIS, rozszerzając jego funkcjonalność poprzez autorską wtyczkę, w której zaimplementowano narzędzia morfologii matematycznej oraz zmodyfikowano do bieżących potrzeb inne istniejące narzędzia. Do wybranych czynności wykorzystano również środowisko ArcGIS firmy Esri. Proponowany sposób implementacji zasad generalizacji zakłada półautomatyczny tryb pracy, w celu umożliwienia kartografowi stałej kontroli nad przebiegiem procesu. Na podstawie przeprowadzonych prób generalizacji można stwierdzić, że implementacja opracowanych zasad w programie QGIS nie jest w pełni możliwa. Ponadto automatyzacja tego procesu jest bardzo czasochłonna i nie daje wystarczająco dobrych efektów. Konieczna jest manualna interwencja kartografa. Uzyskane rezultaty generalizacji są jednak w znacznym stopniu zadowalające.
EN
The goal of this paper was an attempt to formalize and implement the principles of settlements and a road network generalization from a 1:10 000 source map to 1:50 000 scale, in accordance with appropriate legal regulations. Implementation of the cartographic knowledge base was carried out with QGIS by expanding its functionality through a plug-in which implements mathematical morphology operations and some existing generalization algorithms with further modifications. For several operations Esri ArcGIS software was also used. The proposed methodology of implementing the generalisation principles assumes a semi-automatic mode, in order to enable the cartographer to control the entire process. Based on the reported attempts, it can be concluded that the automation of required cartographic rules in QGIS software is not fully possible. Furthermore, the automation of generalisation process is very time-consuming and inefficient. Thus, manual intervention is still necessary. However, the obtained results of map generalisation are in most cases acceptable.
EN
Vision based games is a type of software that can become a promising, modern neurorehabilitation tool. This paper presents the possibilities offered for the implementation of this kind of software by the open source vision library. The methods and functions related to the aspect of image processing and analysis are presented in terms of their usefulness In creating programs based on the analysis of the images acquired from the camera. On the basis of the issues contained in the paper, the functionality of the library is presented in terms of the possibilities related primarily to the processing of video sequences, detection, tracking and analysis of the movement of objects. As part of the work, the software that meets the requirements for modern neurorehablitation games has been implemented. Its main part is responsible for the identification of the current position of the user's hand and is based on the image captured from the webcam. Whereas the tasks set for the user used among others supporting visual-motor coordination. The main subject of the research was the analysis of the impact of the applied methods of initial image processing on the correctness of the chosen tracking algorithm. It was proposed and experimentally examined the impact of operations such as morphological transformations or apply an additional mask on a functioning of the CamShift algorithm. And hence on the functioning of the whole game which analyzing the user's hand movement.
EN
The granulometry operator is a mathematical operator largely employed in the 3D analysis of porous media to estimate the sizes of the pores detected in pervious materials and tissues. Quantifying the total porosity volume in a material with only closed pores is a relatively easy task. A simple numerical analysis of connected void or fluid phase components enables one to obtain such a volume. Unfortunately, for materials and/or tissues with (partly) open porosity granulometry calculations might become excessively time and memory consuming. In this work we suggest a method by means of which the open porosity map can be rapidly calculated on the basis of a pre-calculated distance map.
EN
Bone age is a reliable measure of person's growth and maturation of skeleton. The difference between chronological age and bone age indicates presence of endocrinological problems. The automated bone age assessment system (ABAA) based on Tanner and Whitehouse method (TW3) requires monitoring the growth of radius, ulna and short bones (phalanges) of left hand. In this paper, a detailed analysis of two bones in the bone age assessment system namely, radius and ulna is presented. We propose an automatic extraction method for the region of interest (ROI) of radius and ulna bones from a left hand radiograph (RUROI). We also propose an improved edge-based segmentation technique for those bones. Quantitative and qualitative results of the proposed segmentation technique are evaluated and compared with other state-of-the-art segmentation techniques. Medical experts have also validated the qualitative results of proposed segmentation technique. Experimental results reveal that these proposed techniques provide better segmentation accuracy as compared to the other state-of-the-art segmentation techniques.
10
Content available Morphological sharpening of color images
EN
This paper presents a novel approach to morphological contrast sharpening of image using the multilevel toggle operator. The concept presented here is a generalization of toggle based contrast operator for gray-level images. The multilevel toggle operator is used to enhance the contrast of multivalued images. In order to perform necessary morphological operations the modified pairwise ordering (MPO) algorithm is proposed. It gives the total order of color pixels. For comparison four other ordering methods are used. The main advantage of the proposed sharpener is its significant contrast enhancing ability when using MPO. Theoretical considerations as well as practical results are shown. Experimental results show its applicability to low-contrast color images.
EN
The paper presents a comparison of results of the automatic extraction of built-up areas, based on fractal analysis and granulometric maps, in the aerial images. Built-up areas as a land-use class can be clearly seen in an aerial or satellite image, due to its high granularity, but for the same reason they are very difficult to extract using a “traditional” non-contextual, pixel-based classification. Both approaches presented in the paper, using fractal analysis and morphological granulometry, base generally on a pixel-based classification, but performed on images reviously processed using these two types of processes. Fractal analysis consists in an empirical computing of fractal dimension of parts of an image, using a box-counting method. Such an approach generates an image where pixel values are equal to a fractal dimension values of their neighbourhood. Since we can interpret a fractal dimension as a level of granularity, a simple reclassification of such an image can improve a performance of an automatic extraction of built-up area effectively. The approach based on a morphological granulometry creates a number of granulometric maps – images where pixel values mean an amount of objects of certain size in a set neighbouring fragment of an image. This way a number of these images can be processed using a pixel-based classification, to perform an effective extraction of built-up areas in an image. The results of the presented approaches have been compared to the reference mask obtained basing on a visual interpretation of the image.
EN
This paper describes the automatic region of interest selection method in virtual slide images for assessment of pathomorphological diagnostic. The proposed method for identification of high concentration of immunopositive cancer cells is based on specimen area recognition, segmentation of the immunopositive cells, local maxima recognition on cell density map and function of penalty to avoid the too high concentration of the selected ROIs. The obtained results confirm, that average 8.6±1.4 of 10 reaction fields chosen manually were compliant regionally with regions selected automatically, which is a high compliance of specimen histological examination.
PL
W pracy zaproponowano metodę automatycznego wyboru obszarów zainteresowań w obrazach wirtualnych preparatów jako narzędzie wspierające diagnostykę patomorfologiczną. Zaproponowane metoda identyfikacji obszarów o wysokiej koncentracji immunododatnich komórek nowotworowych bazuje na wydzielaniu obszaru tkanki z obrazu, segmentacji komórek immunododatnich, wykrywaniu lokalnych maksimów na mapie gęstości rozkładu komórek oraz zaproponowanej funkcji kary w celu uniknięcia nadmiernej koncentracji zwracanych obszarów zainteresowań. Wyniki liczbowe wskazują, iż średnio 8.6±1.4 na 10 wybranych pól manualnie oraz automatycznie jest tożsamych obszarowo, co skutkuje wysoką zgodność oceny histologicznej przypadków.
EN
This paper describes the sequential extended regional maxima transformation combined with the contrast-based criterion for establishing a sub-optimal h-value. This method is applied to computed tomography angiography and histological image segmentation. The presented method is effective for high and low contrasted arteries, which are detected in 94.3% exactly and in 97.7% with area tolerance, and also for cell nuclei segmentation with near 95% of accuracy.
PL
W pracy przedstawiono zastosowanie transformaty rozszerzonych maksimów lokalnych połączoną z kryterium opartym na kontraście celem ustalenia suboptymalnej wartości parametru h. Zaproponowana metoda została wykorzystana do analizy obrazów tomografii komputerowej naczyń oraz obrazów histologicznych. Okazała się ona wysoce skuteczna dla identyfikacji naczyń z różnym poziomem zakontrastowania, pozwalając na około 96% ich rozpoznawalność, jak również blisko 95% skuteczność w segmentacji jąder komórek w obrazach mikroskopowych.
PL
Artykuł jest poświęcony badaniom możliwości wykorzystania metod analizy granulometrycznej: profilu morfologicznego oraz map granulometrycznych w wykrywaniu budynków na obrazach satelitarnych. Przedstawiono pokrótce podstawy teoretyczne analizy granulometrycznej obrazu i porównano dwie wykorzystywane w badaniach metody. Testy przeprowadzono na fragmencie sceny satelitarnej QuickBird – obrazie wielospektralnym, poddanym wyostrzeniu na podstawie obrazu panchromatycznego. Porównano 8 wariantów klasyfikacji, różniących się pod względem wykorzystywanych danych oraz zastosowanego modelu. Ocenę efektywności poszczególnych wariantów klasyfikacji oparto na analizie wartości współczynnika zgodności kappa oraz błędów nadmiaru i pominięcia. Uzyskane wyniki wskazują na istotny potencjał zaproponowanych metod, natomiast analiza zaobserwowanych niedoskonałości pozwala określić kierunki ich rozwoju.
EN
The article is focused on the analysis of possibilities of using granulometric analysis methods: the morphological profile, and granulometric maps in detecting buildings on satellite images. It briefly explains the theoretical basis for granulometric analysis of image and compares two methods used in research. Tests were carried out on a fragment of QuickBird satellite scene – pansharpened multispectral image. 8 variants of classification differing in terms of the data and the model of classification were compared. Evaluation of the effectiveness of the different options for classification based on the analysis factor kappa values and omission and commission errors. The results indicate the significant potential of the proposed methods, and analysis of the observed imperfections allows to specify the possible fields of their development.
EN
The aim of this paper is to present a possibility to use information technology in the form of databases for processing and analyzing large image sets based on methods of image analysis and mathematical morphology. Up to now the use of databases in the image analysis process has been reduced to storing large amounts of data in the form of images. However, all transformations and analyses of such sets are made on user’s computers. This requires a large data set (images) to be sent by network each time, and also it may possess the problems resulting from managing such large amounts of analyzed photographs on a computer. The proposed approach completely eliminates these problems by moving all transformations of image analysis to a database platform. For this purpose a set of routines realizing transformations of the image analysis and mathematical morphology was developed. The proposed approach allows the unification of the image processing and analysis area and advanced statistical analyses of obtained parameters describing geometrical sizes of objects on photographs. The proposed methodology was illustrated by practical realization of two measurement types for a simple structure of copper concentrate and more complicated, from the point of view of image analysis, structures such as dolomites from Redziny and Laskowa Gora and sandstones from Tumlin and Wisniowka.
EN
In the following work we have shown the use of the image analysis for tracking selected properties rock on video sequences recorded on thin sections. There have been proposed algorithms that were supposed to outline transcrystalline cracks and mineral of biotite. In both algorithms, an important role played the change of the polarization in the microscope. In the past, image analysis was used to measure properties rock, however, most of the methods proposed by the scientists were based on still images. Algorithms outlining rock parameters using video sequences are a new approach to the use of image analysis in the geotechnical studies. Studies described in this paper were carried out with the use of video material which showed thin sections of dolomites from Rędziny and granites from Strzelin. The analysis required several methods of image processing, such as: point processing, contextual processing and morphological image processing in order to determine a displacement vector of objects on the pelting frames of the video sequence followed by biotite plaque and transcrystalline crack segmentation. Correct measurement results obtained in the studies give hope to implement those methods in utilitarian applications. It will allow automatization and objectification of the measurements conducted for the geological and geoengineering purposes. Moreover, proposed methods may be the basis of the product which in quick and fully automatized manner may carry out geotechnical measurements. The results of such measurements will be independent from the observer, thus, reproducible and objective.
PL
W niniejszej pracy zaprezentowano wykorzystanie analizy obrazu do śledzenia wybranych struktur skalnych na sekwencjach wideo zarejestrowanych na szlifach cienkich. Postanowiono zaproponować algorytmy mające na celu wyznaczanie szczelin śródkrystalicznych i blaszek biotytu. W obu algorytmach istotną częścią badań była zmiana położenia polaryzatora w mikroskopie. W przeszłości stosowano analizę obrazu do pomiaru właściwości skalnych, jednakże większość proponowanych przez badaczy metod bazowało na zdjęciach. Algorytmy wyznaczające parametry skał wykorzystujące do tego celu sekwencje wideo, są nowym podejściem stosowania analizy obrazu do badań geotechnicznych. Badania opisane w niniejszej pracy były prowadzone na materiale filmowym, który obrazował szlify cienkie dolomitu z Rędzin i granitu ze Strzelina. Jego analiza wymagała zastosowania szeregu metod przetwarzania obrazów, takich jak np. operacje punktowe, kontekstowe oraz przekształcenia morfologiczne w celu wyznaczenia wektora przesunięć obiektów na następujących po sobie klatkach sekwencji wideo, a następnie segmentację blaszek biotytu i szczelin śródkrystalicznych. Poprawne wyniki pomiarów osiągnięte w ramach badań dają nadzieję na implementację tych metod w zastosowaniach utylitarnych. Pozwoli to na zautomatyzowanie i zobiektywizowanie pomiarów prowadzonych na potrzeby geologii i geoinżynierii, ponadto zaproponowane metody stanowić mogą podstawę produktu, który w sposób szybki i w pełni zautomatyzowany pozwoli na pomiary geotechniczne, a wyniki tych pomiarów będą niezależne od obserwatora a co za tym idzie odtwarzalne i obiektywne.
PL
Niniejszy artykuł porusza temat generalizacji obiektów geometrycznych w bazach danych przestrzennych, na podstawie metod morfologii matematycznej. Zbadano wpływ przykładowych operacji, tj.: erozji, dylatacji, otwarcia i zamknięcia, na stopień szczegółowości danych oraz efektywności czasowej zapytań. Wykazano, iż metody morfologii matematycznej w połączeniu z algorytmami redukcji wierzchołków mogą być traktowane z powodzeniem jako nowatorskie podejście w procesie optymalizacji baz danych przestrzennych.
EN
This article describes the issue of geometric objects generalization in spatial databases with methods of mathematical morphology. The authors studied the impact of exemplary operations, i.e.: erosion, dilatation, opening, closing on the level of the data details and time efficiency of queries. It has been shown that the mathematical morphology methods can be successfully treated as a novel approach in spatial databases optimization.
EN
Solving the periodic narrowband interference and suppression of white noise during the actual detection of partial discharge (PD) are difficult. In this paper, a method of suppressing the interference signal method based on the combination of morphological filters and complex wavelet transform is proposed. Generalized morphological filters based on the principle of mathematical morphology were structured and set as a pre-filter unit to realize pre-treatment of the original PD signals, and complex wavelet transform was then employed to process the PD signals. Finally, denoised PD signals were obtained. Applying this method to deal with the noise in the simulation and acquisition of PD signals, the results showed that the method can restrain effectively the PD periodic narrowband interference and white noise. Compared with the same wavelet base of the wavelet and the complex wavelet denoising methods, this method reduces energy loss and retains well the PD signals characteristics.
PL
W artykule opisano metodę tłumienia zakłóceń (zakłócenia wąskopasmowe, biały szum) w sygnałach, w przypadku wykrycia wyładowań niezupełnych. W rozwiązaniu wykorzystano kombinację filtrów morfologicznych, działających jako pre-filtr i złożoną transformatę falkową do dalszej obróbki sygnałów. Wykonano badania symulacyjne, potwierdzające skuteczność filtracji.
EN
The paper presents an automatic computer system for evaluation of the Fuhrman degree in renal carcinoma, of the accuracy comparable to the human expert. The solution uses the combined methods of mathematical morphology, Hough transform and neural networks for the estimation of Fuhrman degree of the carcinoma clarocellular cells, based on the microscopic kidney image. The results of numerical experiments have shown that the average discrepancy rate between the score of our system and the human expert results estimated on the basis of almost 300 cells is below 10% and this accuracy is acceptable in the medical practice.
PL
Praca przedstawia podejście komputerowe do automatycznej oceny stopnia skali Fuhrmana w przypadku raka nerki. Ocena dotyczy mikroskopowego obrazu nerek. Proponowane rozwiązanie stosuje zespół metod obejmujących morfologię matematyczną, transformację Hougha, sieci neuronowe oraz grupowanie danych wielowymiarowych. Proponowane rozwiązanie zostało sprawdzone na zbiorze prawie 300 obrazów nerek z różnym stopniem zaawansowania choroby nowotworowej.
EN
This paper presents the possibilities of using image processing for determining effective porosity in carbonate and terrigenous rocks. For the purpose of the research, an algorithm was created, which automatically determines the percentage of pore space, based on the analysis of video sequences registered with the use of a microscope. Up to this point stereological research used for describing rock porosity was conducted manually, which is both troublesome and time consuming. The proposed algorithm uses a series of transformation operations such as: non-context operations, contextual operations and morphological transformations. The presented algorithm was tested on video sequences of thin sections of carbonates from Buszewo and Kościan, and sandstones from Dobrzyca and Solec. The obtained results show, that the method of automatic video sequence analysis used for detection and measurement of porosity leads to satisfying results.
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