Features searching

The objects on the surface may be searched and then enumerated using the Command Enum Features. Fig. 3.11 demonstrates what is regarded as object. The average level, mean square deflection (in fig d) and maximum value are calculated for the surface. Then two planes are compared - A and B. The plane A has the height value, which is in the middle between Average level and Maximum height. The plane B is higher than Average level by 2d (d - mean square deflection). The plane which is lower serves as a threshold and the regions of the surface higher than the threshold surface are regarded as objects.

Figure 3.11: Object Search

By the Command Enum Features the marks are put on the image and two windows appears -- First, the histogram window, where the size and square of the objects are shown. It is possible to move two vertical lines in this window so that to select the objects according to the square. Second, the window with table, in which different object parameters is listed. This table contends 4 columns but the column with the object number: Square, Perimeter, Volume and RMS (standard height deviation). In this table user can sort out the objects using any parameter. Objects remunerate after being sorting out. User can select the objects and copy its parameters to a clipboard. To select the objects user should click desired objects, holding CTRL or SHIFT button. To copy user should press CTRL+C or run the Copy Text command from Edit menu.

If the parameter Filter inner is selected in the Menu Features, then only the objects in between these lines will be selected. If the parameter Filter outer is selected, then only the objects outside the lines will be selected.

The selected objects may be deleted, so that their height will be adjusted to the minimal height on of the surface. This is done by the command Features/ Remove filtered from image.

Menu command Features/ Remove filtered from histogram delete non-selected objects from histogram only, and do nothing with the objects on the image.

The command Profile average height из меню Features calculates the average height of the objects. It is done in the following way. The new average level of the height of the surface is found when the selected objects are not accounted for. Then the average height of each selected objects is calculated as the average value among maximum values of the height for each line along X axis in respect to the new average level. After that the average value for the height of all the objects is estimated and shown in the right lower corner of the Window.

The parameter Show mask may be selected in the Menu Features. In this case only the selected objects will be seen. All other regions will be in black color.