The Target Controller may or may not be visible, depending on your THOR workflow tasks. When present, the Target Controller is used to control how targets are defined through the use of one or more rule images. The upper part of the Target Controller contains the list of current targets. The colored box next to the target names indicates the color of the target layer overlaid on the image. Clicking on the target name shows or hides its histogram panel. To change the order in which layers are drawn in the Viewing Area, click and drag the list items into the desired order. The top item in the list is drawn on top.

The Snapshot button below the Target Controller will create a JPEG image of the current Viewing Area contents.

When two or more targets are being examined, select the Co-Targets option to see where those targets co-occur. Use the M of N Targets slider to indicate how many targets must co-occur in the same pixel to display it as a co-target. Use the ROI Color box to set the color used to indicate co-targets. The Opacity slider adjusts the opacity of the co-target layer (100 is completely opaque, 0 is completely transparent).

The figure below shows an example of the Co-targets tool. White pixels are designated as valid targets by more than one target layer, potentially indicating target confusion: