Menu | Tools > HIPS and SIPS > Sound Velocity Correction (Kongsberg) |
CARIS Batch | Sound Velocity Correct HIPS (Kongsberg) |
Sound Velocity Correction contributes to a more accurate soundings file by applying travel time and angle information into across-track and depth values. The process combines transducer orientation and positioning data from the HIPS vessel file with Sound Velocity Profile data and applies a ray-tracing algorithm.
The sound velocity correction process uses a ray tracing algorithm to apply the sound velocity profiles. You can use either regular attitude data or smoothed data for applying vessel motion data to the ray-tracing algorithm.
It is recommended that sound velocity correction be applied to bathymetry data that does not have a full SVC before cleaning the data. Whenever SVC is applied, the Georeference Bathymetry command will also need to be applied to the data to obtain properly processed HIPS data. |
Interface
Each method of applying sound velocity correction has its own dialog box, which displays the specific options that can be applied using that method. These dialog boxes are displayed below.
Option | Description |
|---|---|
Input source | 1. Select “All track Lines”. |
Options: General | |
Sound Velocity Profile File | SVC will use either the sound velocity profile from your converted data, or the last SVP file applied to the data. If SVC has been previously applied, the name of the SVP file used will be displayed in the SVP File field. To select an SVP file: 1. Click the check box to enable the Browse button. 2. Navigate to and select the profile file to apply. |
Profile Selection Method | 1. Select a method from the drop-down list: • Previous in time: Apply the SV profile with a time stamp just prior to and nearest to the time of the recording of the survey data. • Nearest in time: Apply the SV profile that was taken closest in time to the recording of the survey data. • Nearest in distance: Apply the SV profile that was taken closest to the position where the survey data was recorded. This requires that positions be included in the SVP file. • Nearest distance within time: Apply the SV profile with a position that is nearest to the swath and has a time stamp that is nearest to the time of the swath, within a selected range. • Last used method: Apply the last selected profile method to the current SVC. If a line has not had SVC applied previously, attempting to use Last used method for correction will cause the process to fail. In this case, choose another SVC method. |
Nearest Distance Hours | If the Profile Selection Method is set to Nearest in distance within time, this field is enabled. 1. Type the number of hours to use with the Nearest in distance within time profile selection method. |
Options | |
Heave source | 1. Set the type of heave to be applied when the data is merged in Georeference Bathymetry. • Realtime: Original heave data will be used. • Delayed: Delayed heave data will be used If you choose this option but no delayed heave data is available, the Output window will display a warning message and the regular heave data will be used instead. |
Procedure
1. Select a track line or group of track lines.
2. Select the Sound Velocity Correction command.
3. Set options in the Sound Velocity Correction dialog box.
4. Click OK.
Output
Lines which have been sound velocity corrected will be displayed in the Display window in the “Not merged” colour (as set in the Properties for the Ship Track Lines layer).
The SVP Corrected field in the Selection window will show “Yes” for any selected line to which SVC has been applied.
You can also view the SV profile information in the process Log Viewer:
1. Open the Log Viewer from the Window> Other Windows menu.
2. Select Sound Velocity Correct using Kongsberg Library from the left column of the Log Viewer.
The SVC information is listed in the right column of the viewer.