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How-to Qimera - Importing Processed Point Files


Processing Point File Data in Qimera 1.0

The purpose of this document is to outline how point file data is processed in Qimera 1.0.
On this page:


Adding Processed Point File Data

  1. Once a Project has been created in Qimera, Processed Point File Data can be added by selecting the 'Add Processed Point Files' from the Casual Prompt.


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2. Also Processed Point File Data can be added through the Menu Source > Add Processed Point Files and by right clicking on the 'Processed Point Files' item in the Project Sources tree.
    When any of these options are used the Processed Point Files dialog will appear.

3. Here, Point file data can be entered either by clicking on the 'Add Files...' button, or by clicking on the 'Add Directory...' button. Clicking on the 'Add Files...' button will bring up a file selection dialog and multiple files can be added at once.
    Clicking on the 'Add Directory...' button will bring up a directory selection dialog. This will recursively add any supported Point File Data.


In the case where there are multiple supported Point File Data, a filter can be specified in the Filter edit field.

For a list of all the supported processed point files please see Qimera Supported Data Formats - Processed Point Files.

Please note that Qimera will handle up to 42 million points/soundings or the creation of a QPD file of up to 2GB in file size when loading Processed point files. 


4. If an ASCII file is added, Qimera will automatically prompt for Custom ASCII File Configuration.

5. Please see How-to Qimera - Custom ASCII File Import for a detailed description of the custom ascii import wizard.

Once the ASCII configuration has been set, the Add Processed Point Files dialog will now have the following ASCII Configuration options:

The exact XYZ fields can be specified and the Z field can be inverted. Clicking on the 'Custom Parser Configuration...' button will give the option to reconfigure the ASCII file setup.


It is very important to make sure the Coordinate System of the Imported Data is specified.
Qimera will try to make an educated guess, based on the Coordinate System of the Project that is created.
However, you can import data with a coordinate system that does not match with the project.

Point File Data Interaction

  1. When point file data has been added to the project, it is added to the Project Sources tree under the parent item 'Processed Point Files'.


2. Each file is then scanned for Metadata. You can see the progress of this scan in the Job Activity monitor. Also as each file has been scanned, the associated item in the Project Sources tree goes from disabled to enabled.
    To see the properties and metadata for any Process Point File, click on the file in the Project Sources tree and then click on the Properties window.


3. Once the metadata for each Point File has been scanned, a calculated center line track is added to the main Work area of Qimera. Selecting any file in the Project Source tree will highlight the file's center line track and vice versa.
    Multiple lines can be selected from either the Project Sources tree or the Work area using the Ctrl key or the Shift key.


4. Right clicking on the Project Sources Tree for any selected Processed Files gives you the option to 'Edit File Configuration...' or 'Edit TPU Setup'. Edit File Configuration will bring up the following dialog:


5. The file type is displayed and a table displaying all the input fields for the current input files. The Mapping column indicates how a given field is used during the process operations. By changing the Mapping values, different fields can be used for both the value to grid as well as the X and Y value. In addition to changing which fields are used, any field can also be inverted by setting the Modifier column to Invert. The second tab in the configuration dialog is the Flags control that is used to specify which input flags are used to reject data during any process operations. This table contains two columns. One to display the flag name, and another to specify whether to accept or reject data that has the given flag set to true.

6. TPU Calculation Setup presents a dialog used to calculate the Horizontal and Vertical TPU values for each sounding in the file. This setup is only necessary when building a Dynamic Surface with CUBE. If this setup is not done before building a Dynamic Surface with CUBE then this dialog will be prompted when building a Dynamic Surface.

7. There are four options for the source of TPU:

      1. If the Point File format contains precomputed TPU values, then the first option the dialog presents for setup is to use those default values. If the format does not contain TPU values this option will not be presented in the dialog.
      2. The next option is to calculate the TPU based on Depth using IHO S-44 Standard.
      3. The third option is to assign the TPU based on a standard deviation in fixed percentage of the depth value for each sounding.
      4. The final option is simply assign a constant value used for all soundings for both vertical and horizontal TPU.

In the case where an ROV collected the data, the depth value does not reflect the actual depth relative to the ROV at collection time.
For cases such as this an additive depth shift can be added. This option is under Assign TPU based on Depth (IHO S-44 Standard).

Processed Point File Operations

  1. Qimera supports three operations for Processed Point Files: 
    1. Build Static Surface
    2. Build Dynamic Surface
    3. Export Processed Points
    4. Unload Edits to original processed point file

  2. With the exception of Unloading, all these operation can be done with Raw Data as well, since Raw Data create QPD files, and QPD files are point files themselves. So documenting how these operations work is not needed here.

  3. When the choice is made to build a Dynamic Surface, the Dynamic surface creation process involves the creation of QPD files which represent all the soundings from the original Processed Point files. 
    1. For every Processed Point file that is used to build a Dynamic Surface, a unique QPD file is created and stored in the project under /DtmData/PointFiles/.
    2. If building a Dynamic Surface with CUBE, a dialog will appear to enter how the TPU values for each sounding will be calculated. This can always be changed at a later time by right clicking on the processed point file(s) from the Source tree.
    3. All edits made to the file through the Dynamic Surface tools are saved directly to the QPD file. Edits from the qpd can be applied back to the original processed point file by using the unload tool in Qimera. This can be found under the Dynamic Surface menu or by right clicking on the selected processed point file(s) in the Source tree. For a list of all formats that support unloading, refer to Qimera Data Format Information.

4. If Processed Point files need no editing and are simply brought into the project to build a static surface or export the processed point files, these operations will use the original Point File data.

5. If a Dynamic Surface was created, the generated QPD files will be used to build the static surface and export to Processed Point files to ensure all edits made to the QPD files are included.

6. If the File Configuration has been changed for any Processed Point File loaded in Qimera, and that Processed Point file has an associated QPD file, the QPD file will automatically be regenerated. Before the QPD is regenerated, a warning will pop up because any edits made to the QPD file will be lost.