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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KilletSoft provides solutions for problems with large NTv2 files in GIS and Geosoftware
With a new program and new features of GeoDLL it is possible to copy from very large
NTv2 files, such as BY_KanU and BWTA2017, only the required areas into smaller NTv2 files

April 12, 2018
Dipl.-Ing. Fred Killet - Killet Software Ing.-GbR - Escheln 28a - 47906 Kempen, Germany
 Download Press Release as MS WORD file

Logo For Bavaria and Baden-Wurttemberg (Germany) NTv2 approaches already exist with very high accuracy in the centimeter range, which are suitable for the transformation of spatial thematic data of the real estate cadastre. The high point density required for this results in a high count of meshes in the NTv2 files. As a result, the file sizes of the NTv2 grid files for the two large-area Federal States are enormous. For example, the NTv2 file BY_KanU_Bayern-gesamt.gsb, just in development by the Bavarian Surveying Administration, has a volume of more than 3.18 gigabytes. The productive file BWTA2017 of the Federal State of Baden-Wurttemberg has still a size of 374 megabytes.
The use of such large NTv2 files is a new trend that developers of geodetic software and GIS could not anticipate. Thus it is not surprising that BY-KanU by a lot of software products can not be used. Here, the file size exceeds the by "long integer" addressable file range of about 2.2 gigabytes. Often the grids of the NTv2 file are held in memory due to the calculation speed. However, this is usually not possible with such large grids as contained in BY-KanU and BWTA2017. These problems can be eliminated only with a great development effort and require a certain changeover time.
Copy of a NTv2 area KilletSoft has developed a tool as part of its GeoDLL, which allows to copy out a required area from a large NTv2 file by defined corner coordinates. The separated area is placed in a new NTv2 file that is much smaller than the original. Thereby all subgrids whose area intersects the given area are taken into account. The newly generated NTv2 file now can be used as usual in all geodetic programs and GIS. If, for example, only the Munich area is needed for coordinate transformation using NTv2, with the KilletSoft tool it can be cut out from the Bavarian NTv2 file BY-KanU by defining the corner coordinates of the area of Munich. In a test, conducted by KilletSoft, the resulting NTv2 file only had the 120th part of the original file size.
Beside NTv2 coordinate transformations and datum shifts GeoDLL contains several functions for manipulating NTv2 files:

  1. convntvascii2bin() - Converts a NTv2 ASCII file to a binary file
  2. convntvbin2ascii() - Converts a NTv2 binary file to a ASCII file
  3. convntvbin2area() - Copies an area from a NTv2 grid file to new file
  4. getntvheader() - Determines the header parameters of an NTv2 file
  5. getntvgridheader() - Determines the header parameters of all subgrids

In addition to NTv2-based coordinate transformation, these features as of now can be placed into your own software products using KilletSoft's GeoDLL. Shortly, another function will be available to customize NTv2 files with their Polygonal Validity Scope (see  working paper dated Dec., 2015). For this a shape file with the outer borders of the validity scope area will be used. KilletSoft will soon develop a computer program that will apply the functions mentioned here to NTv2 files. Still in this year, KilletSoft will introduce another program that can generate own NTv2 files from identical points in two different frames of reference.

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 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 NTv2 Hamburg
Highly accurate NTv2 file of the Federal State of Hamburg free of charge for TRANSDAT and GeoDLL users.
 Download the NTv2 file ...
 Read the Press Release...

KilletSoft Logo GeoDLL
GeoDLL provides Time Zone Calculations with aspect to Maritime Territorial Limits.
 Read the Press Release...

KilletSoft Logo TRANSDAT / GeoDLL
The program and the DLL now support all HARN / HPGN Reference Systems of the United States.
 Read more...

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.