Elliptic Fourier descriptors of cell and nuclear shapes

Author(s):  
Giacomo Diaz ◽  
Corrado Cappai ◽  
Maria Dolores Setzu ◽  
Silvia Sirigu ◽  
Andrea Diana
Author(s):  
Miroslav Havlíček ◽  
Šárka Nedomová ◽  
Jana Simeonovová ◽  
Libor Severa ◽  
Ivo Křivánek

Although recently reported models for determining egg shape are highly accurate, certain com­pli­ca­ted measurements or computations are to be performed. Thus relatively simple and attainable analysis methods of chicken egg shape variability were chosen and used for the purpose of presented research. Sample of 250 eggs of ISA BROWN strain was examined. Geometrical parameters were measured and calculated with following expression of their coefficient of variation – namely egg length 3.56 %, egg maximum width 2.84 %, shape index 3.80 %, surface area 5.08 %, and egg volume 7.23 %. The second method consisted in shape quantitative measuring by the score of the principal components of elliptic Fourier descriptors (EFDs). The first four principles components which could explain over 99 % of the egg shape variations were found to be very good measures of the monitored phenomenon. It was found that 87.41 % of the total shape variation can be accounted to length to width ratio. Usefulness and relevance of the shape index usage was confirmed.


2019 ◽  
Vol 61 (3) ◽  
pp. 245-256 ◽  
Author(s):  
Bünyamin Demir ◽  
Bahadır Sayinci ◽  
Necati Çetin ◽  
Mehmet Yaman ◽  
Ruçhan Çömlek

2020 ◽  
Vol 9 (8) ◽  
pp. 482
Author(s):  
Juan Francisco Reinoso-Gordo ◽  
Rocío Romero-Zaliz ◽  
Carlos León-Robles ◽  
Jesús Mataix-SanJuan ◽  
Marcelo Antonio Nero

Sometimes it is necessary to know the transformation to apply to a mapping shape in order to locate its true place. Such an operation can be computed if a corresponding reference object exists and we can identify corresponding points in both shapes. Nevertheless our approach does not need to match any corresponding point beforehand. The method proposed defines a polygon in the frequency domain—two periodic functions are derived from a polygonal or polygon. According to the theory of elliptic Fourier descriptors those two periodic functions can be expressed by Fourier expansions. The transformation can be computed using the coefficients of the harmonics from the corresponding shapes without taking into account where each polygon vertex is placed in the spatial domain. The transformation parameters will be derived by a least squares approach. The geomatics and geosciences applications of this method go from photogrammetry, geographic information system, computer vision, to cadaster and real estates.


2002 ◽  
Vol 52 (4) ◽  
pp. 243-251 ◽  
Author(s):  
Hiroyoshi Iwata ◽  
Hirohisa Nesumi ◽  
Seishi Ninomiya ◽  
Yasushi Takano ◽  
Yasuo Ukai

2000 ◽  
Vol 50 (2) ◽  
pp. 73-80 ◽  
Author(s):  
Hiroshi Iwata ◽  
Satoshi Niikura ◽  
Seiji Matsuura ◽  
Yasushi Takano ◽  
Yasuo Ukai

2018 ◽  
Vol 69 (4) ◽  
pp. 271
Author(s):  
B. Demir ◽  
B. Sayıncı ◽  
N. Çetin ◽  
M. Yaman ◽  
R. Çömlek ◽  
...  

Size and shape data of agricultural crops provide great sources for food processing technologies. The physical attributes of different fruits should be known for the design, developing and innovation of food technologies. In this study, the size and shape distinctions of fifteen national and international walnut cultivars (Midland, Sütyemez-1, Serr, Maraş-18, Maraş-12, Sütyemez-2, Kaman-1, Kaman-5, Pedro, Howard, Chandler, Şebin, Şen-2, Bilecik and KR-1) were determined using elliptic Fourier and multivariate approaches. Firstly, the gravitational features of walnut cultivars were determined, and their dimensional, area and shape attributes were revealed by image processing. Cluster analysis was used to designate the walnut cultivars. Elliptic Fourier descriptors obtained from walnut outlines provided the comparisons among walnut cultivars in shape. The shape index indicated that Serr, Sütyemez-2, Midland and Şen-2 cultivars were oval-shaped, and the others were spherical. The cluster analysis divided the walnut cultivars into four subgroups. Elliptic Fourier descriptors perfectly distinguished the walnut cultivars according to shape.


2021 ◽  
Vol 1 (2) ◽  
pp. 1-7
Author(s):  
Kavi K. Oza ◽  
Rinku J. Desai ◽  
Vinay M. Raole*

Leaves are most important part of the plant and can be used for the identification of a taxon. An appropriate understanding of leaf development in terms of shape and responsible abiotic factors is necessary for improvement in plant. Leaf shape variation could be evaluated successfully, and the symmetrical and asymmetrical elements of the overall shape variation could be detected. The aim of the present study was to establish a quantitative analysis method of leaf shape by elliptic Fourier descriptors and principal component analysis (EF-PCA). EF-PCA describes an overall shape mathematically by transforming coordinate information concerning its contours into elliptic Fourier descriptors (EFDs) and summarizing the EFDs by principal component analysis. We can be able to extract six variables by using leaf specimen images from field and herbarium specimens. In the present study, total leaf area with respect to notch area is more variable within species. Within a species the major source of the symmetrical elements may be governed by genotypic features and the asymmetrical elements are strongly affected by the environment. We could discuss the value of morphometrics to detect subtle morphological variation which may be undetectable by human eye.


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