Overlays

ENVI User's Guide: Interactive Display Functions

Overlays

Use Overlay to place annotation (text, polygons, symbols, etc.), classifications, density slices, pixel and map grids, contour lines, regions of interest (ROIs) or vector layers over an image or plot.

Tip
Use ENVI's QuickMap feature to quickly overlay grid lines, titles, declination diagrams, North arrows, and borders on georeferenced images. For details, see Creating QuickMaps.

Showing and Hiding Overlay Dialogs and Layers

When working with overlays (annotation, regions of interest, contours, grid lines, density slices, and vector layers), you can hide the control dialog (e.g., the ROI Tool dialog, the Density Slice dialog, etc.) without erasing the corresponding overlays from your image. When the dialog is hidden, you can hide the associated layers without erasing them.

Hiding Overlay Dialogs

To remove the overlay control dialog from the screen or hide it without erasing overlays from your image, select one of the following options:

In the overlay control dialog, select Options

Hide Window.

In the Window Finder, double-click on the window name.

Showing Hidden Overlay Dialogs

To unhide the overlay control dialog, select one of the following options:

In the Window Finder (see Using the Window Finder), click on the window name.

From the Image window menu bar, select Overlay

overlay type.

Hiding Layers

When an overlay control dialog is hidden, you can show or hide the displayed layers:

To hide layers, select Overlay

overlay type Hide Layer. All of the layers of the selected overlay type are hidden.

To unhide layers, select Overlay

overlay type Show Layer.

ENVI Online Help (August 12, 2005)