To use the ROI measurement tools,
Select the Region of Interest annotation button.
Left-click with the mouse on the image.
While holding down the left mouse button, drag the cursor to expand the defined region.
Release the mouse button to get the region area.
The default region of interest drawn on the image is a true circle. When resizing the ROI, maintain a true circle by using the corner grab points.
If the image object does not contain pixel size and spacing information, measurements are displayed in pixels. To convert pixels to real-world dimensions, you must calibrate the image.
To adjust the annotation graphic using the mouse,
Click on the Annotation button to enter annotation mode
Select the annotation you want to change.
To resize the graphic, left-click on one of the grab points along the edge or ends of the graphic and drag the mouse.
To move the graphic, left-click the edge of the graphic that is not a grab point and drag the mouse.
To adjust the annotation graphic by small amounts using the keyboard,
Click on the Annotation button to enter annotation mode
Select the annotation you want to change
Press the Tab or Shift+Tab key to select the side, edge or other object you want to adjust. When you press the Ctrl key (see next step), the selected side, edge or other object is highlighted.
Press the Ctrl+<direction> key to move the selected side, edge or other object. The <direction> key can be an arrow key, Home to move up and to the left, End to move down and to the left, Page Up to move up and to the right, and Page Down to move down and to the right.