scholarly journals Affine Transformation for Landmark Based Registration Initializer in ITK

2011 ◽  
Author(s):  
Eun young Kim ◽  
Hans Johnson ◽  
Norman Williams

This document describes an affine transformation algorithm as an additional feature for landmark based registration in ITK www.itk.org. The algorithm is based on the paper by Spath, H [1]. The author derives a set of linear equations from paired landmarks and generates an affine transform from them. The method implemented here gives more freedom in the choice of registration and/or initialization method in ITK. The submission describes ITK implementation of the algorithm.

2011 ◽  
Vol 403-408 ◽  
pp. 2400-2403
Author(s):  
Hua Ying Liu ◽  
Chen Chen ◽  
Fang Zhou Zhang ◽  
Miao Gong ◽  
Xu Yan Wang

There are several transformation methods between different coordinate system. This article adopts affine transformation and least square principle, deduces from conversion between geographic coordinates system and the pixel coordinate system theoretically, and conducts a better control aiming at the error. Finally, an example was demonstrated in this article to prove the rationality and practical value of this algorithm.


2014 ◽  
Vol 716-717 ◽  
pp. 1341-1345
Author(s):  
Wen Ming Guo ◽  
Gang Wang

Because the affine transformation can realize the coordinate translation, rotation, scaling, it is applied to calibrate the touch screen. But,requirements for touch errors of Windows 8 is ±0.5mm,and the pass rate of sample point must reach 4%.Therefore, simply use the method of draw-point to collect the sample point has been unable to meet the requirement of accuracy. This paper tries to propose two improved calibration algorithm based on affine transform, one method use drawing lines instead of marking point, the other devides the screen into a plurality of areas to use multiple calibration. This two kind of methods can effectively improve the calibration precision.


Author(s):  
K. Thangamania ◽  
R. Ichikari ◽  
T. Okuma ◽  
T. Ishikawa ◽  
T. Kurata

This paper discusses the algorithm to detect the distorted textures in the virtualized reality indoor models and automatically generate the necessary 3D planes to hold the undistorted textures. Virtualized reality (VR) interactive indoor modeler, our previous contribution enables the user to interactively create their desired indoor VR model from a single 2D image. The interactive modeler uses the projective texture mapping for mapping the textures over the manually created 3D planes. If the user has not created the necessary 3D planes, then the texture that belong to various objects are projected to the available 3D planes, which leads to the presence of distorted textures. In this paper, those distorted textures are detected automatically by the suitable principles from the shape from texture research. The texture distortion features such as the slant, tilt and the curvature parameters are calculated from the 2D image by means of affine transformation measured between the neighboring texture patches within the single image. This kind of affine transform calculation from a single image is useful in the case of deficient multiple view images. The usage of superpixels in clustering the textures corresponding to different objects, reduces the modeling labor cost. A standby database also stores the repeated basic textures that are found in the indoor model, and provides texture choices for the distorted floor, wall and other regions. Finally, this paper documents the prototype implementation and experiments with the automatic 3D plane creation and distortion detection with the above mentioned principles in the virtualized reality indoor environment.


2015 ◽  
Vol 10 (2) ◽  
Author(s):  
Afifurrahman Afifurrahman

Abstrak: Geometri fraktal merupakan cabang matematika yang memfokuskan kajiannya pada objek-objek fraktal. SFI yaitu teknik yang dapat digunakan untuk memodelkan objek fraktal. Tulisan ini memaparkan bagaimana mengaplikasikan teorema Collage untuk mendesain SFI suatu himpunan K  yang memiliki  sifat self-similarity. Mendesain SFI suatu himpunan K  berarti mencari sejumlah berhingga pemetaan kontraktif berupa transformasi affine: dengan  sedemikian sehingga  untuk n=1,2,…,N. Keenam parameter pada persamaan di atas disebut sebagai kode SFI. Penelitian ini bertujuan untuk merancang suatu algoritma berdasarkan ide dari teorema Collage dalam menentukan kode SFI yang akan digunakan untuk memvisualisasikan atraktor dari objek fraktal menggunakan bahasa pemrograman. Algoritma yang telah disusun selanjutnya diterapkan untuk memperoleh SFI motif songket Lombok dan diperoleh hasil sebagai berikut:dengan faktor kontraktivitas s = 0.70434.Kata Kunci: Teorema Collage; Sifat Self-Similarity; Transformasi Affine; Algoritma; SFI; Atraktor. Abstract: Fractal geometry is the branch of mathematics that focus its studies on fractals. Iterated Function Systems (IFS) acts as a technique to generate fractal models. This article presents how to implement the Collage Theorem to design IFS of  K  which hold self-similarity property. Designing IFS of K  means that finding the finite contractive mapping i.e. affine transformation:  where   such that  for n=1,2,…,N. The six parameters on the equation above are called IFS codes. The aim of the study is constructing the algorithm based on the Collage theorem to determine the IFS codes which are used to visualize the attractor of the fractal objects through programming language. The Algorithm is implemented to obtain the IFS of Songket’s texture of Lombok and the result is given below:with a contractivity factor s = 0.70434.Keywords: Collage Theorem; Self-Similarity; Affine Transformation; Algorithm; IFS; Attractor.


2020 ◽  
Vol 5 (02) ◽  
pp. 167
Author(s):  
Nur’enny Nur’enny ◽  
Rahmat Hidayat

This study aims to obtain information about extrinsic motivation and work experience and its effect on employee performance in the Serang Baru District Office. This study uses a saturated sample so that the population is the same as the sample of 80 employees, at the Serang Baru District Office. The method used is validation test, reliability test, then classical assumption test, which includes normality test and multicollinearity, as well as heteroscedasticity test, multiple linear analysis test, multiple linear equations, F test, coefficient of determination, and t test. The data of this research used observation methods and questionnaires distributed to 80 samples which were addressed to employees of the Serang Baru District Office. Based on the results of research and discussion, it can be concluded: 1) Extrinsic motivation does not affect employee performance because employees are willing to work more than expected regardless of extrinsic motivation or not. 2) Employee performance is strongly influenced by work experience. The more experience, they get while working, the more knowledge they will get. 3) Employee performance will be better with the support of experienced employees so as to increase the level of output produced.             Keywords: Employee Performance, Extrinsic Motivation, Work Experience


2011 ◽  
Vol 2 (3) ◽  
pp. 56-58
Author(s):  
Roshni .V Patel ◽  
◽  
Jignesh. S Patel

Author(s):  
CHEN Qi ◽  
LI Haitao ◽  
LI Ping ◽  
YANG Xinrong
Keyword(s):  

Author(s):  
Bernhard M¨uhlherr ◽  
Holger P. Petersson ◽  
Richard M. Weiss

This chapter presents some results about groups generated by reflections and the standard metric on a Bruhat-Tits building. It begins with definitions relating to an affine subspace, an affine hyperplane, an affine span, an affine map, and an affine transformation. It then considers a notation stating that the convex closure of a subset a of X is the intersection of all convex sets containing a and another notation that denotes by AGL(X) the group of all affine transformations of X and by Trans(X) the set of all translations of X. It also describes Euclidean spaces and assumes that the real vector space X is of finite dimension n and that d is a Euclidean metric on X. Finally, it discusses Euclidean representations and the standard metric.


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