Viewing 3D object properties

Property

Unit

Description

Vertices

-

Number of vertices in the 3D object

Triangles

-

Number of triangles in the 3D object (a measure of surface complexity)

Reference point

degrees or meters

Geographic position of the reference point at which the 3D object has been placed

N-S length

m

Maximum length of the 3D object in the north/south axis

E-W length

m

Maximum length of the 3D object in the east/west axis

Minimum depth (below mean sea level)

m

Minimum depth (below mean sea level) of the 3D object

Maximum depth (below mean sea level)

m

Maximum depth (below mean sea level) of the 3D object

Height

m

Maximum height of the 3D object

Created

dd/MM/yyyy HH:mm:ss.sss

Date and time that the 3D object group was created in Echoview

Acquired

dd/MM/yyyy HH:mm:ss.sss

Date and range of times that the data was collected, i.e. the time span over which the data on which the object is based was acquired.

For example, "Acquired: 14/05/1999 23:09:58.000 to 23:10:19.500" means that the data from which the school was detected was collected on 14 May 1999 from all pings at or between 9 minutes 58 seconds past 11 p.m. and 10 minutes 19.5 seconds past 11 p.m.

Acquired defaults to unknown.

This metric is only available for objects which were created from echogram data. This does not include raster images or 3D models.

Valid

dd/MM/yyyy HH:mm:ss.sss

Date and time range for which the data can be considered useful.

This metric is only available for objects which were created from echogram data. This does not include raster images or 3D models.

Property

Unit

Description

Surface area

m2

Surface area of the surface

Property

Unit

Description

School detection algorithm

-

The 3D school detection algorithm used to detect schools in the 3D region. Refer to 3D school detection algorithms for more information.

Surface area

m2

Surface area of the 3D region

Volume

m3

Volume of the 3D region. This does not include the volume of any vacuoles in the 3D region. To include the volume of vacuoles add Total vacuoles volume (below).

Note: Volume calculations in analyses prior to the Echoview 5.4 release may be affected by the introduction of Bad data (empty water) regions. Volume may increase when a bad data (no data) region completely covers a bad data (empty water) region.

Geometric center

degrees or meters,
degrees or meters,
meters (below mean sea level)

Geographic position and depth (below mean sea level) of the point at the geometric center of the 3D region. If using the UTM projection, geographic position is measured in eastings and northings. Other projections use longitude and latitude.

First beam area

m2

Surface area at the intersection of the 3D region and the first beam in the variable used to create it (by school detection). Note: this does not refer to pings in the variable chosen for analysis, but pings in the variable used for school detection.

Last beam area

m2

Surface area at the intersection of the 3D region and the last beam in the variable used to create it (by school detection). Note: this does not refer to pings in the variable chosen for analysis, but pings in the variable used for school detection.

Max range area

m2

Surface area at the intersection of the 3D region and the maximum recorded range in the variable used to create it (by school detection). Note: this does not refer to pings in the variable chosen for analysis, but pings in the variable used for school detection.

First ping area

m2

Surface area at the intersection of the 3D region and the first ping in the variable used to create it (by school detection). Note: this does not refer to pings in the variable chosen for analysis, but pings in the variable used for school detection.

Last ping area

m2

Surface area at the intersection of the 3D region and the last ping in the variable used to create it (by school detection). Note: this does not refer to pings in the variable chosen for analysis, but pings in the variable used for school detection.

Total intersection surface area

m2

Sum of the First beam area, Last beam area, Max range area, and Last ping area

OBB dimensions

m, m, m

Longest, next longest and shortest dimensions of the 3D object-aligned bounding box.

The depicted 3D object is a 3D region that was created by a 3D school detection on multibeam data.

A 3D regions' bounding box is a 3D region metric and the box can be displayed in a scene.

OBB orientation

degrees, degrees, degrees

The elevation, azimuth and rotation of the object bounding box's axes, defined as follows:

Elevation: the angle between the longest axis of the object-aligned bounding box and the horizontal. Ranges from -90 (vertical downwards) through 0 (horizontal) to 90 (vertical upwards).

Azimuth: the angle between the longest axis of the object-aligned bounding box and north. Ranges from 0 (north) through 90 (east) and 180 (south) to 360 (north)

Rotation: the angle of rotation of the second longest axis of the object-aligned bounding box about the longest axis when viewed in the upward sense of the longest axis. Ranges from 0 (horizontal) to 90 (most upward direction) to 180 (horizontal).

Roughness

/m

Surface area of the 3D region divided by volume of the 3D region

Vacuoles

-

Number of vacuoles contained within the 3D region.

Total vacuoles volume

m3

Volume of all the vacuoles in the 3D region. Property only displayed when vacuoles are present.

Property

Unit

Description

Location

Latitude (degree) Longitude (degree) at depth (meters below mean sea level)

Latitude, longitude and the depth (below mean sea level) of the point.

Time

dd/MM/yyyy

HH:mm:ss.sss

Average valid time for the point.

Intensity

dB

Intensity records the mean Sv of the 3D region this point represents. If the mean Sv could not be calculated at the time of detection this value will be -9.9e+37. See Integration from scenes for further information.

It can be used to determine the display color for the point. To do so, you must select the Intensity display method on the Display page of the 3D Object Properties dialog box for the 3D region track group (i.e. all the 3D points in all the 3D region tracks in a 3D region track group share the same intensity display definition).

Velocity

m/s, m/s, m/s

Velocity of the 3D region moving from the previous point to the current point, expressed as three speed components of the velocity vector in three orthogonal directions as follows [Latitudinal component, Longitudinal component, Depth component].

This is not available for the first point in a track (as there is no previous point from which to measure velocity by this definition).

Property

Unit

Description

Location

Latitude (degree) Longitude (degree) at depth (meters below mean sea level)

Latitude, longitude and the depth (below mean sea level) of the point.

Time

dd/MM/yyyy

HH:mm:ss.sss

Average valid time for the point.

Intensity

-

Intensity can record any value useful to you and is specified in the .epl file from which the polylines were imported.

It can be used to determine the display color for the point. To do so, you must select the Intensity display method on the Display page of the 3D Object Properties dialog box for the 3D polyline group (i.e. all the 3D points in all the 3D polylines in a 3D polyline group share the same intensity display definition).

Velocity

m/s, m/s, m/s

Velocity of the 3D region moving from the previous point to the current point, expressed as three speed components of the velocity vector in three orthogonal directions as follows [Latitudinal component, Longitudinal component, Depth component].

This is not available for the first point in a track (as there is no previous point from which to measure velocity by this definition).

Property

Unit

Description

Location

Latitude (degree) Longitude (degree) at depth (meters below mean sea level)

Latitude, longitude and the depth (below mean sea level) of the point.

Time

dd/MM/yyyy

HH:mm:ss.sss

Valid time for the point. This is the time of the ping for the single target.

Intensity

dB

Intensity records the TS of the single target this point represents.

It is used to determine the display color for the point.

Property

Unit

Description

Location

Latitude (degree) Longitude (degree) at depth (meters below mean sea level)

Latitude, longitude and the depth (below mean sea level) of the point, that represents a single target in the valid fish track region used during creation of the 3D fish track.

Time

dd/MM/yyyy

HH:mm:ss.sss

Valid time for the point. This is the time of the ping for the single target in the valid fish track region used during creation of the 3D fish track.

Intensity

dB

Intensity records the TS of the single target this point represents.

It is used to determine the display color for the point.

Velocity

m/s, m/s, m/s

Velocity of the single target moving from the previous point to the current point, expressed as three speed components of the velocity vector in three orthogonal directions as follows [Latitudinal component, Longitudinal component, Depth component].

This is not available for the first point in a track (as there is no previous point from which to measure velocity by this definition).

Property

Unit

Description

Bitmap color bits

-

Number of bits used to represent color in the image

Stored bitmap width

pixels

Width of the image

Store bitmap height

pixels

Height of the image

Beams

-

Number of beams in the multibeam ping this curtain represents

Data points

-

Number of data points in the multibeam ping this curtain represents

Property

Unit

Description

Live updating from variable

-

Is displayed only if the Live update option was set when the echogram curtain was created. Indicates that this echogram curtain will respond if pings are added to or removed from the specified variable.

Property

Unit

Description

Bitmap color bits

-

Number of bits used to represent color in the image

Stored bitmap width

pixels

Width of the image

Store bitmap height

pixels

Height of the image

Property

Unit

Description

Bitmap color bits

-

Number of bits used to represent color in the image

Stored bitmap width

pixels

Width of the image

Store bitmap height

pixels

Height of the image

North-west corner

degrees  or meters

For each section, you can view:

• the geographic position coordinates at which each corner of the raster image is positioned.

• the Depth in the water column at which each corner of the raster image is positioned.

Notes:

• Geographic position units and values will differ depending on the projection currently selected in Echoview (on the Mapping page of the EV File Properties dialog box). Values entered into the Import 3D Raster Image dialog box will be in the units appropriate for the projection currently selected in Echoview (either degrees of latitude and longitude or meters of eastings and northings).

• Echoview will display a raster image with corner coordinates exactly as entered.  Therefore, when these coordinates are within those of the current scene but do not correspond to the coordinates expected from the image dimensions, the raster image will be distorted. When entered coordinates are outside those of the current scene, the imported raster image will not be visible.

• GeoTIFF images contain the geographic coordinates corresponding to image corners. This information may be read by utility programs, such as listgeo which is available from https://trac.osgeo.org/geotiff/

North-east corner

South-west corner

South-east corner

Property

Unit

Description

Model loaded from file

-

File name and path of the 3D model object that was imported into the EV file

Note: This file exists independently of the 3D object in Echoview

Normals

-

Number of normals in the 3D object file

Facet normals

-

Number of facet normals in the 3D object file

Materials

-

Number of materials in the 3D object file

Groups

-

Number of groups in the 3D object file

Material library

-

Material (.mtl) file related to the 3D object file