Global Mapper Pro

XTF files

Ian Ramcharan
Ian Ramcharan Global Mapper User
edited July 2014 in Suggestion Box
I noticed in the latest version of GM the Triton XTF format is available for import. However when i import an XTF file it seems to provide just data points rather than the raster image. Can you explain the purpose of this?

Comments

  • global_mapper
    global_mapper Administrator
    edited October 2009
    The XTF import is still a bit of a work in progress. We were waiting for more input from the original requester to determine how to interpret the sonar data to generate a raster image, but they have yet to respond. If you have any knowledge about how to turn the sonar scan information into a raster it would be helpful.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • Ian Ramcharan
    Ian Ramcharan Global Mapper User
    edited October 2009
    The XTF import is still a bit of a work in progress. We were waiting for more input from the original requester to determine how to interpret the sonar data to generate a raster image, but they have yet to respond. If you have any knowledge about how to turn the sonar scan information into a raster it would be helpful.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com

    Hello Mike, i can send you a pdf with the XTF data format as well as a sample XTF if you like. Is the support@globalmapper.com e-mail the best to use?
  • global_mapper
    global_mapper Administrator
    edited October 2009
    I actually already have the format specification and sample data. The XTF format does not directly contain a raster image, instead for sonar it contains sonar samples with a series of values for each sample (I think this is some kind of return ping at each angle or something). I can decode the point data and attributes, I just don't know how to turn that into a raster sonar image.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • Ian Ramcharan
    Ian Ramcharan Global Mapper User
    edited October 2009
    I actually already have the format specification and sample data. The XTF format does not directly contain a raster image, instead for sonar it contains sonar samples with a series of values for each sample (I think this is some kind of return ping at each angle or something). I can decode the point data and attributes, I just don't know how to turn that into a raster sonar image.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com

    Understood. There really isn't that much of a need to import XTF's as generally the sonar data needs to be "processed" (smooth vessel track, apply layback, apply gains, bottom tracking etc.). To produce a geotiff you apply the processing steps first so the XTF remains your raw format. Also there are xtf viewers available if someone wants to just view the data.

    Out of curiosity what GlobalMapper displaying for the XTF? It looks like a sonar track with attribute information for the pings etc.
  • global_mapper
    global_mapper Administrator
    edited October 2009
    What Global Mapper currently imports is a separate point feature for each sonar "ping", with a list of attributes for all of the raw samples (voltage values I think) associated with that ping.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • Radon222
    Radon222 Global Mapper User Trusted User
    edited November 2009
    What Global Mapper currently imports is a separate point feature for each sonar "ping", with a list of attributes for all of the raw samples (voltage values I think) associated with that ping.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com

    Mike,

    Do you know what kind data the original poster is working with? XTF files can contain bathymetric XYZ data, vertical subbottom profile acoustic imagery, or most commonly Sidescan sonar imagery.

    If its sidescan sonar, the imagery is mapped like aerial flyover with each "Sample" depicted as a pixel and assigned a 8bit color value (0-254). Somewhere in the header for each ping should info defining the position and heading, and range scale for the data.

    I'm not a programmer, but I could probably point you to a few with a lot of experience writing this kind of code.

    At least the XTF format is somewhat standardized. If anyone ever asks you to start reading SEG-Y files.... just run! lol.
  • global_mapper
    global_mapper Administrator
    edited November 2009
    The XTF data in this case is the side-scan sonar data. I'm able to extract each ping data set and a series of attributes that I think are voltage values either at different angles or ranges, but I'm not sure. If an expert on this can try the latest v11 build and load their sonar XTF data they might be able to provide some insight on how to convert the point features that Global Mapper currently creates into a better picture.

    In the meantime until someone expresses significant interest in this I'm not going to bother with it.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • DELPH
    DELPH Global Mapper User
    edited November 2009
    Hi,

    A Side-Scan Sonar data file is a log of signal time-series from both sides of the sensor: Accoustic 'pings' from the sonar refect in time on the seabed and are returned echoes are listened by the sonar. The received sound is translated into voltage signals and recorded by the sonar logger in XTF format.

    To make a map of such data (usually called a mosaic including multiple records to do coverage), a combination of navigation processing (so multiple lines can match in space), signal processing (to compensate from noise attenuation, beam angles, etc.) and image processing (to create a raster) are necessary.

    All of those tasks can be performed by using appropriate software. DELPH Sonar (http://delph.ixsea.com) will perform all those tasks and produce the side-scan sonar map in geoTIFF and KMZ format so data can be rapidely visualized in Geographic Information Systems (GIS) or even GoogleEarth.

    Philippe
    http://delph.ixsea.com
  • global_mapper
    global_mapper Administrator
    edited November 2009
    Philippe,

    Thanks for the information. For now users can use the DELPH Sonar software to create the GeoTIFF and KMZ files, then load those in Global Mapper. If there is a large demand for more advanced built-in support for XTF in Global Mapper then I'll look into adding something like that directly into Global Mapper.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • Keef_2
    Keef_2 Global Mapper User
    edited July 2014
    Sorry to drag up this old thread, but it seemed relevant. I was trying to use the 15.2 xtf import tool and kept getting an error as attached. This was an xtf file generated from a scanline starfish 990f sonar. Any idea what I am doing wrong?
    starfish.PNG
  • Keef_2
    Keef_2 Global Mapper User
    edited July 2014
    Here is a link to a sample dataset from the manufacturer Download Windermere1.xtf
  • PShorey
    PShorey Global Mapper Developer Moderator, Trusted User
    edited July 2014
    Hi Keef.

    You're not doing anything wrong. I was able to reproduce the error. Working on a fix now.
  • Keef_2
    Keef_2 Global Mapper User
    edited July 2014
    Fantastic, thanks for looking at this. :D
  • PShorey
    PShorey Global Mapper Developer Moderator, Trusted User
    edited July 2014
    OK, problem fixed. The first few ping locations were invalid (0, 0) and the code was not handling that properly. The fix will be available in the next update.
  • global_mapper
    global_mapper Administrator
    edited July 2014
    I have incorporated Peter's change in to a new build. I have placed new builds with the latest changes at the links below:

    32-bit: http://www.bluemarblegeo.com/downloads/global-mapper/global_mapper15.zip
    64-bit: http://www.bluemarblegeo.com/downloads/global-mapper/global_mapper15_64bit.zip

    Simply download the .zip file for the build that you are using and extract over your existing installation files. The likely locations to extract to are as follows:

    32-bit: C:\Program Files (x86)\GlobalMapper15
    64-bit: C:\Program Files\GlobalMapper15_64bit

    Thanks,

    Mike
    Global Mapper Guru
    geohelp@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation
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