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Easiest way to create a .ggf Geoid file from CSV, TIFF, or BIL?

  • 1.  Easiest way to create a .ggf Geoid file from CSV, TIFF, or BIL?

    Posted 06-25-2020 02:43

    I have a local Geoid file in CSV, TIFF and BIL format and want to create a .ggf file for use in Trimble Mobile Manager. What is the easiest way to convert to .ggf file format?



  • 2.  Re: Easiest way to create a .ggf Geoid file from CSV, TIFF, or BIL?

    Posted 07-23-2020 16:37

    Hi Sebastien. Can you provide a bit more context on the structure of the data in the CSV? We do have an older tool that can be used to construct a ggf file, but it functionally requires a matrix of orthometric-to-ellipsoidal (geoidal) height offsets using a consistent grid size.



  • 3.  Re: Easiest way to create a .ggf Geoid file from CSV, TIFF, or BIL?

    Posted 07-23-2020 23:14

    Hey Matt, thanks for the response! The data I have is from the Austrian Federal Office for Metrology and Surveying, it contains height differences between ellipsoidal heights and heights above a regional vertical reference system in a 15 x 22.5 arcsecond grid with 2D-coordinates in a local geographic CRS (EPSG 4312). I assume you are talking about Trimble Grid Factory? I have heard about the tool but didnt't have enough time to look into it yet. Any advice on how to avoid rookie mistakes while working with Grid Factory is much appreciated !  



  • 4.  Re: Easiest way to create a .ggf Geoid file from CSV, TIFF, or BIL?

    Posted 07-24-2020 17:27

    Yep - Trimble Grid Factory which we still make available here. There exists a support note from 2009 that I'm trying to source internally as I was able to find it (albeit randomly) on the Internet here. It describes a process for creating a ggf file from data in an Excel sheet.

     

    In addition, I'm poking around internally to see if we have more current utilities that might be able to work with the image format file directly (likely the GeoTIFF). I'll update this thread if I manage to find something.



  • 5.  RE: Re: Easiest way to create a .ggf Geoid file from CSV, TIFF, or BIL?

    Posted 11-18-2022 04:05
    Edited by Tom Harrison 11-21-2022 05:32