Context

Context is an additional object descriptor which describes the neighboring environment of the object. A Background is required to represent the environment.

Note: To compute the context parameter: In the Project menu, click on Preferences. In the Project Preferences window, select Object Extraction, click on the Compute Additional Parameters button and select Context.

Note: This process can be stopped by clicking on its progress bar, after closing the dialog.

In the window Compute Context:

Select a Background (if there is no background, make one)
Choose a border width that represents an external border of the object in pixels.
Select a progression type (from internal border layer to external border layer)

Note: The context parameter creates an external border for every object and counts the border pixels superimposed with pixels of the selected background. If the progression is:

No : All the border pixels have the same weight
Arithmetic ascending : An ascending weight is set from the internal border layer to the external border layer
Arithmetic descending : An descending weight is set from the internal border layer to the external border layer

In the image on the left (created to represent the context concept), the object is green and the border width is 10 pixels. The internal border layer is red and becomes progressively white to the external border layer. When the progression is arithmetic ascending: the redder pixels get more weight.

Note: To display the context parameter in the Data Viewer or in the Object Extraction tool (Objects tab): In the Project Preferences window, select Object Extraction and check the Context (additional) item. The context parameters are not saved in the JMicroVision Project file.