Exporting region definitions

2D and 3D regions are exported independently of one another as follows. See About region dimension for details.

2D regions

The definition of each 2D region in an EV file can be exported to an evr file. This file can then be used to import 2D regions into another EV file.

To export 2D region definitions:

  1. On the Echogram menu, point to Export, Regions, then click Definitions...

  2. Enter a name and location for the .evr file.

  3. Click Save.

-OR-

  1. On the View menu select Regions (opens the Regions window).

  2. On the Region menu, select Export Region Definitions...

  3. Enter a name and location for the .evr file.

  4. Click Save.

3D regions

The definition of a 3D region class object in an EV file can be exported to an wrl file. This file cannot currently be imported into another EV file.

To export a 3D region definition:

  1. On the Dataflow window, select the 3D region class object you want to export.

  2. On the Shortcut menu select Export, Export 3D object.

  3. Enter a name and location for the .wrl file.

  4. Under Save as type click VRML World (.wrl)

  5. Click Save.

2D Region definition file format

This section describes the format of the file that is created when you export 2D region definitions. These files have an .evr file extension and are referred to as EVR files. 3D regions cannot be exported to files of this format.

You can analyze EVR files using any external software that can read text data files. You can also modify EVR files using external software and re-import them into Echoview. If you create or modify EVR files you should do so carefully as Echoview may crash or exhibit other problems on encountering a file that it considers corrupt.

Overall structure

Region definition files are structured text data files. A CR/LF pair terminates each line (this is the DOS convention, not the UNIX convention that uses a single LF to terminate each line).

An EVR file consists of the following parts:

A single line containing the string "EVRG", followed by the EVR file format version number (currently "6"), and the version number of Echoview that created the file. Each of these three fields is separated by a single space. For example:

"EVRG 6 3.00.41"

This line is followed by a single line that contains the number of regions in the file, e.g.:

"2"

This line is followed by the data for region 1, the data for region 2, and so on. The data structure for a single region is described in the next section.

Structure corresponding to a single region

A number of fields are written for each region. Each of these is followed by the separator listed in the following table.

Field

Separator

Description

Blank line 

CR/LF

Region separator 

Region structure version

Space

"13" (will be incremented if the region structure changes in future versions)

Point count

Space

Number of points in the region

Region id

Space

Unique number for each region. Specify sequential numbers starting at 1 if creating a new file

Selected

Space

"0" (always)

Region creation type

Space

See Data formats below

Dummy

Space

Should always be "-1"

Bounding rectangle calculated

Space

"1" if the next four fields are valid

"0" otherwise

Left x value of bounding rectangle

Space

Date and time of left boundary of bounding rectangle – ignored on input when importing into Echoview.

Top y value of bounding rectangle

Space

Upper depth coordinate of bounding rectangle  – ignored on input when importing into Echoview.

Right x value of bounding rectangle

Space

Date and time of right boundary of bounding rectangle  – ignored on input when importing into Echoview.

Bottom y value of bounding rectangle

CR/LF

Lower depth coordinate of bounding rectangle – ignored on input when importing into Echoview.

Number of lines of notes

CR/LF

The number of lines of region notes to follow.

Region notes

CR/LF

Notes associated with the region. Maximum length is 2048 characters. Embedded CR characters are encoded as hexadecimal FF. Embedded LF characters are encoded as hexadecimal FE.

Number of lines of detection settings

CR/LF

The number of lines of detection settings to follow.

Region detection settings

CR/LF

The detection settings as defined in the Fish Track Detection Properties dialog box or Detect Schools dialog box.

Region classification

CR/LF

Region classification (string). Default value is "Unclassified regions"

Point 1

Space

Data for first point – See Data formats below. These data are used to bound the region when importing into Echoview.

...

Space

...

Point N

Space

Data for last point – See Data formats below.

Region type

CR/LF

"0" = bad (no data);

"1" = analysis;

"2" = marker

"3" = fishtracks

"4" = bad (empty water)

Region name

CR/LF

String

Data formats

The region creation type is one of the following:

Region creation type

Description

-1

No type

0

Created from a selection made using the horizontal band tool horizontal selection tool

1

Created from a selection made using the parallelogram tool parallelogram tool

2

Created from a selection made using the polygon tool polygon selection tool

3

Created from a selection made using the rectangle tool rectangle tool

4

Created from a selection made using the vertical band tool vertical selection tool

5

Created as a bottom-relative region or line-relative region

6

Created or assigned as Marker region.

7

Created using the Detect Schools command

8

Invalid or unknown region type

9

Created as a fish track region

The date and time format is in CCYYMMDD HHmmSSssss where:

CC

=

century

e.g.

20

YY

=

year

e.g.

03

MM

=

month

e.g.

01

DD

=

day

e.g.

07

HH

=

hour

e.g.

14

mm

=

minute

e.g.

23

SS

=

second

e.g.

13

ssss

=

sub-seconds

e.g.

2854

Depths are written in meters in decimal notation.

Point data

The data for a single point is encoded as a date, a time, and a depth separated by spaces.

Note: Self-crossing regions are not supported. That is, the line which defines the boundary of the region may not cross itself.

Example file

This file contains 5 regions: a bad data and a marker region, and 3 analysis regions. Regions 1-3 were created with the rectangle tool, Region 4 with the horizontal band tool, and Region 5 is a school detection.

EVRG 7 9.0.213.33208
5

13 2364 10 0 7 -1 1 19960828 0449043100 176.333 19960828 0451140750 240.333
1
school detection
10
School detected with:
Minimum data threshold: -81.00
Maximum data threshold: (none)
Minimum total school length: 40.00
Minimum total school height: 10.00
Minimum candidate length: 5.00
Minimum candidate height: 2.00
Maximum vertical linking distance: 5.00
Maximum horizontal linking distance: 20.00
Distance mode: GPS
Big school
19960828 0449043100 212.3333333333 19960828 0449043100 212.6666666667 19960828 0449051900 212.6666666667 19960828 0449051900 212.3333333333
...
19960828 0449060400 211.6666666667 19960828 0449060400 211.9916666667 19960828 0449060195 212.0000000000 19960828 0449043100 212.0000000000 1
Region 5

13 4 11 0 6 -1 1 19960828 0445322700 -9999.9900000000 19960828 0445331200 9999.9900000000
1
Marker shortcut
0
Unclassified regions
19960828 0445322700 -9999.9900000000 19960828 0445322700 9999.9900000000 19960828 0445331200 9999.9900000000 19960828 0445331200 -9999.9900000000 2
Region4

13 4 12 0 3 -1 1 19960828 0440345500 183.7146702557 19960828 0441368900 234.1857335128
1
Rectangle tool
0
Unclassified regions
19960828 0440345500 183.7146702557 19960828 0440345500 234.1857335128 19960828 0441368900 234.1857335128 19960828 0441368900 183.7146702557 1
Region 1

13 4 13 0 3 -1 1 19960828 0442313750 185.7335127860 19960828 0444022800 233.5127860027
1
Rectangle tool
0
Unclassified regions
19960828 0442313750 185.7335127860 19960828 0442313750 233.5127860027 19960828 0444022800 233.5127860027 19960828 0444022800 185.7335127860 1
Region 2

13 4 14 0 0 -1 1 19960828 0439227417 2.0188425303 19960828 0505041093 73.3512786003
1
Horizontal band tool. bad data type.
0
Unclassified regions
19960828 0439227417 2.0188425303 19960828 0439227417 73.3512786003 19960828 0505041093 73.3512786003 19960828 0505041093 2.0188425303 0
Region 3

See also

About regions