Control Point File Requirements and Formats

  • Updated on Apr 16, 2025
  • Published on Aug 28, 2024
  • 2 minute(s) read

Creating a control point coordinates file (poses)

Control point coordinates Posesshould be measured by a surveyor, using a total station. To use the poses in post-processing, they must be must be created in either the .txt or .csv formats.

Control Point File Requirements

The control point file must meet the following conditions:

  • Surveyed coordinates must be in a right-handed coordinate system.

  • Always include the z-coordinates of the surveyed control point poses. Datasets scanned with the NavVis M6 and the NavVis VLX will be undistorted in the z- as well as x- and y-directions.

  • For each dataset, at least 3 control points need to be recorded and need to be contained in the surveyed control point file.

  • All coordinate values must be in the metric system.

  • Geo-referenced coordinates can be used.

  • If you are using a local coordinate system (the origin is arbitrarily self-defined), then the origin should not be too far from the scanned site, ideally no more than a few kilometers. If the data is more than 20,000 meters away from your site origin, you will not be able to add your data to your NavVis IVION site.

Control Point File Format

The surveyed control points can be in .txt or .csv format.

CSV format

.csv files can be exported from e.g. Microsoft Excel. Make sure to use the following format:

CP00001, 1000.458, 1964.458, 0.1
CP00002, 1005.000, 2000.000, 0.2
CP00003, 1002.862, 2025.802, 0.3
# CP-wrong, 9002.212, 3025.432, 5.3. This entry will be ignored with "#" symbol

  • Each line must contain the following values for each control point: ID (name), X, Y, Z (coordinates).

  • Separate all values in each line with commas. Other delimiters cannot be interpreted by the software.

  • Empty lines and data beyond the fourth column will be ignored.

  • Exclude lines by adding # to the beginning of the line.

TXT format

A .txt control point file must be set up in the following format:

CP00001 1000.458 1964.458 0.1
CP00002 1005.000 2000.000 0.2
CP00003 1002.862 2025.802 0.3
# CP-wrong 9002.212 3025.432 5.3 This entry will be ignored with "#" symbol

  • Each line must contain the following values for each control point: ID (name), X, Y, Z (coordinates).

  • Separate the fields with a space.

  • Empty rows and data beyond the fourth column will be ignored.

  • Exclude lines by adding # to the beginning of the line.

FAQ

What formats can the control point coordinates file be created in?

The control point coordinates file can be created in either .txt or .csv formats.

Do the surveyed coordinates need to include z-coordinates?

Yes, the z-coordinates of the surveyed control point poses must always be included.

How many control points are required for each dataset?

At least 3 control points need to be recorded for each dataset.

Can I use a local coordinate system for the control points?

Yes, but the origin should not be too far from the scanned site, ideally no more than a few kilometers.

Is it necessary for all coordinate values to be in the metric system?

Yes, all coordinate values must be in the metric system.

What should I do if I want to exclude a line in the control point file?

You can exclude a line by adding a # symbol to the beginning of the line.

Can I use geo-referenced coordinates in the control point file?

Yes, geo-referenced coordinates can be used.

What happens if the data is more than 20,000 meters away from the site origin?

If the data is more than 20,000 meters away from your site origin, you will not be able to add your data to your NavVis IVION site.

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