What
is ENVISYS?
The main graphical user interface component of Verification is the viewer in which map data and the SAR image are displayed. Initially, the SAR image is displayed together with the oil slick masks and the land mask. The land mask may help the user to inspect slicks near the land more thoroughly since look-alikes are frequent along the coastline. The user may also display other layers on top of these: a territorial border map, a potential spill source map and wind and sea current data. The territorial borders map helps the user to distinguish between slicks within national, foreign and international territories. When it is difficult to determine from the SAR image alone whether some spot is an oil slick or not, the potential spill source map may be useful. An oil refinery near the spot is an indication of a high probability of this spot being a real oil slick. The wind and sea current data are of help in interpreting the SAR image.
A set of image enhancement functions are available in order to enable the user to clearly visualize all information present in the image that may be needed to verify an oil slick. There are also functions for extracting information from the image and for doing geographical measurements. The user may edit the slick masks received from the Detection Module defining the oil area in order to obtain more precise masks, if required.
Finally, Verification permits the user to enter his decision and a comment
into the database. The result is fed back to the Detection Module in order
to update the statistical slick model. In this way the system learns from
experience.
The Verification viewer with menus. The sea is white and land is
green. There are two probable oil slicks in the upper left corner of the
SAR image.
If the situation is threatening commercial or environmental resources, he may switch to the next mode: Assessment.
