Filters

Vessels in the AIS Server are selected through filters, which define groups of vessels. Filters are used when viewing vessels both in lists, on maps, and when exporting data.

Filters are added, edited and deleted using a web-based interface, and are saved on the server. The filter is given an identifying name that is used both when viewing and exporting data.

A filter is composed of one or more filter constraint, and if a vessel satisfies all constraints in a filter, it will be selected. A constraint is defined by an attribute, an operator (either "=", "!=", "<" or ">") and a value. Attributes are usually AIS attributes (such as vessel name, IMO number, position, etc.) but could also be certain calculated values.

AIS attributes

At the moment, the following AIS attributes are available:

Ship name
Country
Ship type
Cargo
Ship operation
Rate of turn
Speed over ground
Course over ground
Heading Destination
Length
Longitude

Latitude
Navigational status
Position accuracy
RAIM flag
MMSI number (list)
IMO number (list)
Call sign (list)
Destination (list)
Source type
Source name

Calculated attributes

Some calculated attributes are also available:

Active
Inactive time
Max speed over ground

Missing dynamic data
Missing static data
Inconsistent data

In addition it the user can specify a map region to be used as default map region and a geographic position to be used for calculating distance from a vessel.

Filters Vessels in the AIS Server are selected through filters, which define groups of vessels. Filters are used when viewing vessels both in lists, on maps, and when exporting data. Filters are added, edited and deleted using a web-based interface, and are saved on the server. The filter is given an identifying name that is used both when viewing and exporting data. A filter is composed of one or more filter constraint, and if a vessel satisfies all constraints in a filter, it will be selected. A constraint is defined by an attribute, an operator (either "=", "!=", "<" or ">") and a value. Attributes are usually AIS attributes (such as vessel name, IMO number, position, etc.) but could also be certain calculated values.

AIS attributes At the moment, the following AIS attributes are available:
Ship name Country Ship type Cargo Ship operation Rate of turn Speed over ground Course over ground Heading Destination Length Longitude	Latitude Navigational status Position accuracy RAIM flag MMSI number (list) IMO number (list) Call sign (list) Destination (list) Source type Source name
Calculated attributes Some calculated attributes are also available:
Active Inactive time Max speed over ground	Missing dynamic data Missing static data Inconsistent data
In addition it the user can specify a map region to be used as default map region and a geographic position to be used for calculating distance from a vessel.