Killet Software Ing.-GbR - short: KilletSoft - is a software company, which was established in the year 1991. The society is divided into the ranges "Geodetic Standard Software", "Development Tools for Geoinformatics" and "International Geodata". The focal trades of the companies supplied by KilletSoft are consulting engineers, GIS developers, Internet marketing, public utilities, logistics, telecommunications, security and public services.
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Polygonal Validity Scopes

NTv2Poly Geosoftware replaces the rectangular activity scope contained in NTv2 files with a Polygonal Validity Scope, which is realized with an outline file in classic Shape Format. Invalid calculations outside the Polygonal Validity Scope thus can be excluded or acknowledged by a warning.

NTv2Poly - Version 1.17 - Last update on 20 June 2018
The latest important changes  History of Changes and Supplements

  1. Graphical views improved.
  2. Added NTv2 files and shape files from Canada and Germany for testing.
  3. Fixed problem processing of very large NTv2 files and shape files.
  4. Added a new graphics window "Area Distribution"
  5. Added a new graphics window "Polygonal Validity Scope"

Polygonal Validity Scopes

Main Window of the program NTv2Poly
Main Window of the program NTv2Poly

Main Window
Distribution of Areas as Example of Canada
Distribution of Areas as Example of Canada

Distribution of Areas
Polygonal Validity Scope as Example of Canada
Polygonal Validity Scope as Example of Canada

Polygonal Validity Scope

Using NTv2 grid files it is possible to transform points from one coordinate reference system to another with very high accuracy. An NTv2 file contains one or more quasi-rectangular coordinate grids which are defined in the NTv2 headers. Instead of a rectangular area only an embedded polygonal area should and must be covered, for example, a state territory within the country borders.

The program NTv2Poly realizes Polygonal Validity Scopes in NTv2 files. Using so prepared NTv2 files, coordinates outside the validity scope can be excluded from calculations or they can be acknowledged by a warning. This works with coordinate transformations using the geospatial software TRANSDAT and GeoDLL by KilletSoft and with many GIS programs which support Polygonal Validity Scopes.

NTv2Poly - Detailed Program Description
Inserting Polygonal Validity Scopes into any NTv2 Binary Files using outlines from classic Shape Files

The Polygonal Validity Scope is realized with a shape file, which contains the outlines of the scope as polygons. The file format Shape is developed by ESRI as a format for geographical objects. For example, in the shape file the border outlines of a country may be stored, which represent the polygonal scope for the NTv2 file used in that country. Using the program NTv2Poly the polygons of the shape file and the quasi rectangular surface of the NTv2 file are superimposed one on the other and processed in an ingenious manner.

The term "exopolygonal entry" used in the course of the text stands for the entry of a characteristic value in a grid mesh of an NTv2 file to exclude this grid mesh from the scope of the NTv2 file. It follows that all grid meshes with exopolygonal entries are invalid. The program NTv2Poly marks all grid meshes that lies outside the polygons of the used shape file as invalid by introducing exopolygonal entries in the NTv2 file.

By using exopolygonal entries in the shift values or in the accuracy values of the NTv2 file, there are two methods for realizing Polygonal Validity Scopes, which both are supported by the program. The two methods differ considerably in their effects.

  1. Exopolygonal entries replace the accuracy values of the grid meshes.
    Exactly one grid mesh is addressed at the grid point of a coordinate. Exactly this grid mesh is defined by the grid point and addressed regarding the interpolation of a coordinate that lies within. This grid mesh is excluded from the polygonal validity scope of the NTv2 grid.
  2. Exopolygonal entries replace the shift values of the grid meshes.
    With a bilinear interpolation the four adjacent grid points of a coordinate are used. Each may contain exopolygonal entries. So, all in all four grid meshes are addressed and each has one grid spacing in northern and southern direction and one grid spacing in western and eastern direction from the grid point. These are the four grid meshes that are arranged around the grid point. Exactly these four grid meshes are excluded from the polygonal validity scope of the NTv2 grid.

The use of Polygonal Validity Scopes is described in detail in our  Worksheet "Proposal for using Polygonal Validity Scopes in NTv2 grid files".

The program has a user-selectable multi language interface and comes with extensive online help. The program can be run on most common networks and it is possible to use Terminal Services on WINDOWS Servers. In case of a network installation the clients are installed automatically by the program.

Multilanguage support

The program NTv2Poly is equipped with a modern graphical user interface of which handling is to understand intuitively. For each window detailed help texts can be shown. The detailed electronic documentation of the program NTv2Poly is available in both English and German language. However, the user interface can be represented in many languages. For this purpose, external language files are used. When starting the program, it notes which language files are available in the calling directory. The found languages then are provided for selection in a list box. By  creating new language files, new languages can be added to the program NTv2Poly at any time.

Network ability

The program NTv2Poly can be run on most common networks. The client installations works automatically. It is possible to use Terminal Services on WINDOWS Servers like e.g. "Citrix Terminal Server".

Pricing, ordering and licensing

Pricing and ordering information can be found in the  Price list. For available licensing options have a look to the  License page. Order the program with the electronic  Order Form.

Download of the test version

The free test version of the program with a detailed user manual can be  downloaded as ZIP packed file by the Internet. For unpacking the download file you need an unzip program, which you can download  from this side.

KilletSoft News In order that you always are well informed about our company, we write actual news, current information and special offers here into this column.

KilletSoft Logo NTv2 files
Geosoftware for inserting area boundaries as Polygonal Validity Scopes in NTv2 files.
 Read the Worksheet...

KilletSoft Logo Geodata International
A new release ot "Geodata International" is available since July 2018. The database contains 282 contry files with Towns and Municipalities, Town Districts, Coordinates, Postal Codes etc.
 Read more...

KilletSoft Logo NTv2 Toolbox
The new program NTv2Tools provides tools for analyzing and processing of NTv2 files.  Read the Description...

KilletSoft Logo NTv2 files
Geosoftware with Tools for analyzing and processing of NTv2 files.
 Read the Worksheet...

KilletSoft Logo PolyGonal Validity Scopes
The new program NTv2Poly complements NTv2 files with Polygonal Validity Scopes that are taken from an outline shapefile.  Read the Description...

KilletSoft Logo Very big NTv2 files
Solutions for problems with large NTv2 files in GIS and Geosoftware  Read the Press Release...

KilletSoft Logo GDA2020
The new geodetic Reference System GDA2020 of Australia is supported by TRANSDAT and GeoDLL now.  Read the Press Release...
 View the list of CRS...

KilletSoft Logo BWTA2017
Baden-Wuerttemberg has completed the close-meshed NTv2 grid file for the transformation of geodata in real estate cadastres to UTM/ETRS89.
 Read the Press Release...

KilletSoft Logo GoogleMaps / OpenStreetMap
KilletSoft converts Geodata for Navigation in free Map Services.
 Read the Worksheet...

KilletSoft Logo Quality Analysis
Practice oriented Accuracy Verification of the Software TRANSDAT and GeoDLL with an extremely structured NTv2 grid file.
 Read the Worksheet...

KilletSoft Logo Innovation Award 2016
Award 2016 KilletSoft's geodetic software has won for the second year in succession the Innovation Award from the Initiative Small and Medium Enterprises.
 Certificate TRANSDAT...
 Certificate ORTWIN...
 Read the Press Release...

KilletSoft Logo GeoDLL / TRANSDAT
Proposal for using Polygonal Validity Scopes in NTv2 grid files.
 Read the Worksheet...

KilletSoft Logo Translators wanted!
The programs TRANSDAT and SEVENPAR support language files for the programs interface. Since the language dependent texts are managed in external files,  new languages can be added at any time by creating new language files. Everybody who is interested can translate a new language file into his native language for himself and all users.