About Cruisetracks

A cruisetrack represents geographic position data in a position variable, optionally combined with data from an acoustic variable or a bottom points variable. Cruisetracks can also display map backgrounds, using WMTS or WMS maps, for spatial context. The types of cruisetracks in Echoview are:

• GPS fixes
• Bottom classification display
• Alongtrack display
• 3D cruisetracks

Also covered on this page:

• Cruisetrack display controls
• What is plotted where?

See also:

• Using cruisetracks: Define and integrate a region
• Using cruisetracks: Displaying map and waypoint data
• Displaying a WMTS map
• Displaying a WMS map
• About WMTS maps
• About WMS maps
• Using cruisetracks: Calculating the area of a polygon

GPS fixes

GPS fixes cruisetracks are created from position variables and provide information on the status of the GPS data.

To display a GPS fixes cruisetrack, do one of the following:

• On the View menu, point to Cruisetrack, and then click a position variable.
  Note: If you have created multiple filesets you will need to point to the Fileset that derived the raw variable of interest.
• On the Filesets window, double-click a position variable, or select a position variable and click Cruisetrack.
• On the Dataflow window, double-click a position variable icon, or right-click on a position variable icon then click Cruisetrack

Figure 1. Cruisetrack display with GPS fixes.

GPS fixes are displayed in the following way:

• The first fix is displayed as a small black or gray square (top left in the example).
• The last fix is displayed as a small black or gray circle (near bottom right in the example).
• Display of fix and track quality.

Notes:

• If the cruisetrack is synchronized with an echogram or table, the GPS fix selected on the echogram is shown by a black circle and crosshair (towards the top left in the example). You can also double-click on a point on an echogram, or a row in a table, and view that point on the synchronized cruisetrack.
• When you move the mouse along the cruisetrack, the GPS fix closest to the mouse is tracked by a small blue circle (shown adjacent to the mouse in the example).
• Cruisetracks are created from processed GPS fixes. You enter processing settings on the Data page of the Variable Properties dialog box. Good and Bad fixes are only displayed if selected on the Cruisetrack Display page of the Variable Properties dialog box.

• For further information see About GPS fix status and Processing and smoothing cruisetracks.
• To smooth a cruisetrack you must create a virtual position variable using the Kalman GPS smoothing filter operator. See Processing and smoothing cruisetracks for more information.
• Cruisetracks plot the position of the GPS antenna, the position of the platform may be offset from the position of the GPS antenna as defined via the Platform Properties dialog box.
• Position status is also shown on the position status bar on an echogram.
• Cruisetrack coordinate readouts (grid labels, status bar, Details panel, synchronized coordinate box) are always shown in latitude/longitude. Projection settings on the Mapping page still control how maps and spatial data are rendered in the background.
• You can quickly open the Mapping page of the EV File Properties dialog box from the Cruisetrack window by selecting Mapping Properties from the right-click menu or the Cruisetrack toolbar. This allows convenient access to projection and map display settings while working with geographic data.
• Regions can be created and region nodes edited.
• The alongtrack length or area of regions may be displayed in the Echoview status bar.

See also

Using cruisetracks
Processing and smoothing cruisetracks
Adding map and Waypoint files to cruisetracks windows
Cruisetrack keyboard shortcuts
Determining GPS fix status
Determining Ping position status
Mouse pointer duplication

Bottom classification display

A bottom classification produces a bottom points variable that contains geographic and bottom points data. The bottom points cruisetrack may be used to display bottom point class in alongtrack bubble or segment style. The bottom points cruisetrack can be auto-synchronized with a bottom points table, bottom points integram, echograms and Media window. For more information refer to About bottom classification.

To display a bottom points cruisetrack, do one of the following:

• On the View menu, point to Cruisetrack, and then click a bottom points variable.
• On the Dataflow window, right-click on a bottom points variable then click Cruisetrack.

Alongtrack display

The alongtrack display is a color-coded cruisetrack showing integration or other processing results output by a time series variable, where the variable is connected to a platform that is also connected to a GPS variable. Instead of color-coding the cruisetrack, you may choose to display a colored bubble with a size and color for each time series data point. For example, it is possible to create a cruisetrack showing the depth of the sea floor, or the mean Sv value, as seen below. For instructions, refer to Using cruisetracks: Displaying an alongtrack display cruisetrack and Alongtrack Display settings.

To display an Alongtrack display, do one of the following:

• On the View menu, point to Cruisetrack, and then click a variable from the displayed list.
  Note: If you have created multiple filesets you will have to point to the Fileset that derived variable of interest.
• On the Dataflow window, right-click on a variable object then click Cruisetrack.

Figure 2. Alongtrack display, each segment in the cruisetrack shows the mean Sv for every 20 pings of data.

Time series variables that could display alongtrack features include:

• Interval analysis - Bottom feature variable
• Interval analysis - Calibration variable
• Interval analysis - Single targets variable
• Interval analysis - Sv variable
• line variables e.g., sounder detected lines, line pick lines, vegetation lines, threshold offset lines
• transmission time series select variables, time series select variables

Each segment on the cruisetrack shows the specified time series data calculated across a specified range of pings based on time, distance, or number of pings.

Notes:

• Alongtrack results respect all Echoview processing settings (e.g., data thresholds, exclusion lines, bad-data regions). See About setting variable properties for details on how these settings influence output.
• The alongtrack display plots the position of the transducer connected to the upstream acoustic variable, on the Calibration page of the Variable Properties dialog box. If the transducer position varies from the GPS antenna position then the alongtrack display will vary from the cruisetrack of GPS positions.
• An alongtrack display of ping status is not affected by the time/distance grid setting.
• Cruisetrack readouts are always shown in latitude/longitude, independent of the selected projection. The Mapping page projection affects rendering/analysis of background maps and imported spatial data.
• Displayed or created regions can be integrated.
• The alongtrack length or area of regions may be displayed in the Echoview status bar.

See also

Echogram navigation: Mouse Pointer duplication

3D cruisetracks

3D cruisetracks are a 3D object which can be added to scenes.

The 3D cruisetrack plots the position of the GPS antenna. See About transducer geometry for further information about how the position of the GPS antenna is specified.

See Displaying a 3D cruisetrack and Using a 3D cruisetrack for scene animation for further information.

Cruisetrack display controls

For EV file wide map-based color and thickness properties use the Cruisetrack Display page of the EV File Properties dialog box.

Position (GPS) variables and bottom points variables use the Cruisetrack Display under Variable Properties.

Time series variables use the Alongtrack Display under Time Series Properties.

Map background settings (WMTS/WMS) are configured on the Mapping page of the EV File Properties dialog box.

Time slider

Cruisetrack windows include a Time slider control that lets you limit the visible portion of a track to a defined time range. This helps isolate structured survey patterns or periods of interest within longer voyages.

For details about using this tool, see Using cruisetracks: Time slider.

What is plotted where?

Each cruisetrack plots the course of a slightly different point of the echosounder system:

Track type	Position
GPS fix cruisetracks	GPS antenna
3D cruisetracks	GPS antenna
alongtrack display cruisetracks	transducer
bottom classification display	transducer

The About transducer geometry page contains more information on how the GPS and transducer positions interrelate.

See also

Using cruisetracks
Processing and smoothing cruisetracks
Adding map and Waypoint files to cruisetracks windows
Cruisetrack keyboard shortcuts
About color schemes
About setting variable properties
Export positions
Echoview Status bar