© BlueView Technologies Corp
BlueView BV5000 User Handbook
35
XYZ files contain only three values, separated by spaces. OFF files have a two-
line header, followed by a line for each 3D point. Each of these lines has the X,Y,
and Z values, followed by the color assigned to that point, expressed as RGBA.
Each of the X,Y,Z, and RGBA values are separated by spaces.
The color map used assigns blue to the deepest points and red to the shallowest
points. Meshlab and other 3D viewers use this color map to display the points.
Sonar Settings File (.txt)
The .txt file which is created contains information pertaining to the sonar and
scan settings for that scan. The following information is logged: Date and time,
sound speed, calibration setting, TVG, gain, sonar type, threshold setting, physical
offsets and the comments field.
Reviewing Data
When Meshlab is installed and the “Run Meshlab after each scan” box is
checked (File
Æ
Settings
Æ
Recording tab), the OFF file is opened and the 3D
point cloud file can be reviewed.
Reprocessing Saved Data
As previously noted, one of the unique aspects of the BV5000 system is the
ability to store raw scan data and reprocess this data at a later time. Some of the
reasons to reprocess raw data are to:
1)
process with corrected sound speed
2)
process with different threshold settings
3)
process with proper calibration
4)
process with accurate position and orientation data
5)
range gate the data
Even with the most careful procedures, mistakes can be made in the field. With
the ability to fix these problems at a later stage of a project, a significant amount
of time and money can be saved.
