Triton BathyPro accepts data from several different file types for processing. The following guide describes processing of an XTF file to generate a .DDS_VIF image file that can be imported into Triton Delphmap. Triton Delphmap exports the data to GeoTIFF, DXF and Shape files.
The guide describes many of the options available in Triton BathyPro, including the Snippet or Footprint Time Series option. Not all options have to be used for any particular dataset, but as a minimum the following are required for processing any .XTF file and creating a DTM (.DDS_VIF) image:
After entering the basic processing parameters you can hit Process to generate a .DDS_VIF file that can be displayed in Triton Delphmap. You may repeat this after any of the additional processing steps to view the effect in TritonMap .
Start Triton BathyPro:
Before starting a new project Reset Factory Settings
BathyPro will restart.
Right click anywhere in the left panel to open the Add Files dialog and choose Add XTF files (Multibeam Data) unless your data is one of the other listed types.
Add XTF files (MultiBeam Data)... An XTF file logged in Isis/MB-Logger from a Reson Sonar
Add XTF files (Interferometric Data) ... An XTF file logged in Isis from a Klein 5400 Interferometric Side Scan with the Bathy Option
Add XTF files (Single Beam Data)... An XTF file logged in TritonNav with a single beam echosounder.
Add XTF files (Single Beam from SideScan)... An XTF file logged in Isis using a side scan sonar. (BathyPro will Add the SideScan towfish altitude to the towfish depth)
Add XTF files (Auxiliary Channel)... An XTF file logged in Isis/SS-Logger with single beam echosunder written to one of the 6 Auxiliary channels in the XTF.
Add XYZ ASCII file (Multibeam Data)... Any ASCII XYZ file from a Multibeam sonar.
Add XYZ ASCII files (Singlebeam Data) ... Any ASCII XYZ file from a Singlebeam sonar.
Add XYZ Binary file (Simrad format)...
Add XTF files (Submetrix/Simrad/Seabeam Data) ... An XTF file generated from a Triton .ALL (or other) File converter.
Add XTF files (Scanning Sonar Data)... NOT USED
Add XTF files (Benthos C3D)... An XTF file logged in Isis MB/SS-Logger that contains SARA/CAATI format data from a Benthos C3D
See this section for special considerations for the Benthos C3D Sonar.
The following information applies to the Reson sonars.
Select the file you want to process, you can also select multiple files using normal Windows methods
Triton BathyPro scans all the files during project initialization and should report Project Initialization Successful
NOTE: A failure at this point usually means that an incorrect file type has been selected, for example if the file was recorded from a Simrad sonar it could be in .XTF format but an error message will result if (Multibeam Data) was selected instead of (Submetrix/Simrad/Seabeam Data)
Click on Project Settings select Map and Projection settings...
The Map and Projection settings dialog box will open
As a minimum you should check the areas indicated. The Boundaries and North West Origin should resemble the expected values from your data set. The resolution entered should be close to the actual resolution of the Bathymetry in your data; if the resolution entered here is too high (small value) then the resulting files will be large and require a great deal of "filling" (see later) to produce a continuous surface (Digital Terrain Model - DTM). If the resolution is too low (large value) then information may be missing from the DTM.
The default value of 1m is about right for most multibeam sonars operated in 50 - 100m water depth.
Uncheck the Set Default Limit box to enter your own coordinates.
You may also specify different Input and Output projections using the Change buttons. If the navigation data in your files are in Lat/Long format then Triton BathyPro assumes WGS84 as the input Datum and Universal Transverse Mercator as the output Projection. Triton BathyPro automatically chooses the correct UTM zone based on the Longitude of the data.
Check the appropriate box if the expected depth is greater than 2000m
Click OK when all entries are complete
Click on Project Settings select Sensor geometry settings...
The Vessel Geometry dialog box opens
The .XTF file may contain offset information that was entered at the time the data were recorded; you can check the information here, otherwise uncheck Set Default Values (from XTF header) and enter the correct values.
For a more detailed description following this link:
NOTE If you are entering new values you must save them to .GEO file in order for Triton BathyPro to read them during processing, use Save As..
Click on Bathy Processing > Select Processing:
The Select Processing dialog box will open, check the Navigation Processing box, then Settings.. to access the Navigation Processing Settings
You should use the default settings of Sensor Position and Ship Gyro unless you know that the position was stored as Ship Position or that the heading was stored as Sensor Heading or perhaps there was no heading sensor, in which case choose Course Made Good CMG.
It is rarely necessary to change either the Filters or Speed Limits from their default settings
Check the Attiude Processing box, then Settings.. to access the Attitude Processing Settings
These settings almost never need changing.
Check the box, then Settings.. to access the Bathymetry Processing Settings
For detailed information on the settings in this dialog box refer to the Triton BathyPro Manual Bathymetry Processing on Page 61. As a minimum you should leave the default BAD Quality checked to remove any beams that the sonar has flagged as BAD.
Check the Gridding Soundings box, and choose which method you want to use for handling overlapping soundings
You must also select the location and name of the .DDS_VIF file which Triton BathyPro will write. This file is the representation of the 3 dimensional surface (DTM) that will be generated as a result of processing the data, known as the Grid file hence the default name grid00001.DDS_VIF. For more detail see the Triton BathyPro manual Page 66 Gridding Soundings
Bathymetry with its Foot Print Time Series (Snippet) data and sidescan data acquired by Reson 81xx systems can be imported into Triton BathyPro. Mosaics of these two data types can be generated with respect to the bathymetry. Corrections are available in Triton BathyPro to improve the quality of the imagery. The effect of grazing angle and of the range can be removed from the data. Also a migration algorithm removes the hyperbola effects generated by a far range targets.
Not all .XTF files recorded in Isis will contain both Snippet data and Sidescan data, it will depend on whether the sonar hardware supported Side Scan and Snippet data, and whether Isis was configured to save the data. When played back in Isis the windows will look like this if both data types are present:
Click Mosaicing Snippet then Settings to open the Snippet Processing Options dialog box:
Merge Option: these settings decide how the snippet or sidescan data will be handled when it overlaps adjacent data.
Max Amplitude, for any overlapping pixels, keep and display the pixel with the highest amplitude.
Average Amplitude, for any overlapping pixels, keep and display the average value of those pixels.
Sum of amplitude, for any overlapping pixels, keep and display the sum of the amplitudes.
Grazing angle correction: correct for attenuation of the snippet or sidescan data caused by changes in the angle that the beam makes with the seabed and the incident angle at the face of the transducer. Triton BathyPro builds a correction table from this information and allows the user to correct the amplitude of the returning signals in three different ways:
Angular Average an angular reference from the average vector, one average for each unit of grazing angle
Two Angular Averages two references for two angular sectors separated by an angle threshold chosen by the user.
One Global Average a constant reference, the total average of all the samples.
Build table on current File creates a new .CAL file
Use existing file allows an existing .CAL file to be loaded
A uniform dataset will be better corrected for grazing angle effects by using the Global Average option. A dataset with large variations in seabed type would be better using the Angular Average option. Data sets with high amplitude data at the nadir could be corrected by using two Two Angular Averages, one for the nadir and one for non-nadir data
Migration correction checking this box will cause Triton BathyPro to apply a migration algorithm to remove hyperbola effects caused by small high intensity targets at far ranges.
Check the Mosaicing Sidescan to open the same options for processing the sidescan imagery:
This completes the Snippet and Sidscan processing section
Click Store Chart Soundings, then Settings to open the Generate Soundings File dialog box:
Enables the storage of all the processed sounding data in either XYZ ASCII or as a .DXF file. Use this dialog box to specify the location and type of file to be stored, the units of the file, the sign of the depth, and to enable decimation of the data. Setting a Gradient Threshold determines whether data gets decimated or not, so in areas where the topography changes rapidly more data is saved, whereas mostly flat areas will have less data saved.
To export an ASCII XYZ file, check the box Export in ASCII and DXF format the program will then save both an ASCII file and a DXF file.
NOTE: These files can become VERY large.
Click Store Flagged Soundings then Settings to open another Soundings File dialog:
The options available and meanings are exactly the same as the previous description except that the data stored is that flagged for rejection by Triton BathyPro at the Bathy Processing stage.
NOTE: These files can also become large.
Hardware Flagged soundings are sounding that were flagged by the Sonar as being either Poor, Low, or Bad
Click Store Hardware Flagged Soundings then Settings to open another Soundings File dialog:
The options available and meanings are exactly the same as the previous description except that the data stored is that flagged for rejection by the Sonar "Supress Beam using Beam Quality" at the Bathy Processing stage.
NOTE: These files can also become large.
ClickUse RTK value then Settings to open the RTK Processing Settings dialog box:
RTK means Real Time Kinematic and is a high accuracy GPS position which includes an accurate antenna altitude in the output string. If this information is present in the .XTF file then it can be used for tidal corrections in the final data. However, the RTK height information could also contain short term offsets due to heave which would normally be corrected by the motion compensator. This dialog allows the option to remove these short term offsets by averaging the RTK height data over a user selectable period.
ClickTide Correction then Settings to open the Tide Editor:
In the editor you can either enter line by line the time and height of tide, or import a text file with the information. Clicking Open will start the ASCII file importation setup:
The importation routine treats non numeric values within the file as separators, numeric values are 0123456789+- the non-numeric values divide the data into Positions which are then assigned as items, each item is then given a Description and Unit from the pull down menus. In this example item#1 is position 01 and is assigned to Date, item #2 is position 2 and is assigned to Time item#3 is position 03 and is assigned to Tide
Curve options are Linear or Spline.
Click Sound Velocity Correction then Settings to open the Properties for Speed of Sound:
The data here can be entered or imported in exactly the same way as for the Tidal data, there is an additional option to compute the refraction point as the interface between layers or at the midpoint of the layer. If the data are single beam from a conventional echo sounder then the mean water column velocity is entered in Reference Sound Speed for Single Beam
Refraction at Transducer Depth from:
Choose to correct for ray bending at the transducer/water interface either based on information from the velocity graph or from a sensor mounted within the transducer head. In most cases a velocity profile is available so the default is Velocity Profile
Click Along Track Decimation then Settings to access Decimation processing values:
Allows decimation of the along track data based either on time or distance.
Click Snippet Data or Sidescan Data then Settings to select a calibration table file:
These are the files created by Triton BathyPro when Build Table on Current File is selected in Grazing Angle Correction
Processing on Gridded Data
The following operations are performed on gridded data. In Triton BathyPro gridded data means a .DDS_VIF file, which is the output of the steps described up to thios point, these operations are fully described in the Triton BathyPro manual, Page 75 Gridded Data Processing parameters
Fill Gaps Filter
Fills gaps in the DTM based on user settings
Smooth Filter
Smooth the data based on some user settings, note that this operation will actually modify the original data
Isocurves Extraction
Generates a .DXF file of bathymetry contours using the Gridded data (DTM) which can be overlaid on the DTM in Delphmap, or exported to another application.
Generate Grid Chart
Generates a .DXF file with numbered soundings which can be overlaid on the DTM in Delphmap or exported to another application
Click Process to process your .XTF file(s) with all selected options:
You will be given the opportunity save the select processing steps in a .DTM file:
Click Yes to save and select a filename
Triton BathyPro will process all the selected file(s) using the supplied parameters:
In the lower right panel there will be some messages, with a progress bar at bottom left.
The .DDS_VIF file can be viewed in Triton Map, hit Project>Insert Layer:
There will be a .DDS_VIF file with the color-coded bathy data (in this case grid0000.DDS_VIF) and two more files with the snippet data with _snippet added to the file name. The .DDS_VIF will be the actual snippet imagery file and _snippet_track.DDS_VOB will be the vessels tack information (.DDS_VOB is a vector format file in Delphmap)\
All three data types may be displayed in Triton Delphmap:
The vector layers, ships track etc. may be exported as .DXF files, the Color-Coded DTM can be exported as a GeoTIFF image:
Highlight the layer to export in the Project Window, right click to open the export menu. Choose GeoTIFF for the imagery. Triton Map will generate a GeoTIFF geo-referenced image also an associated .TFW (world) file.
If the Project has a projection that is NOT Universal Transverse Mercator the GeoTIFF option may not be available; choose the TIF option. The exported file will not be an internally referenced GeoTIFF, however Triton Map will still export the associated .TFW file, allowing the image to be correctly positioned in other GIS products (Arc View etc.)