Dialog box - Automatic Classification

Use the Automatic Classification dialog box to have the class limits in a classification scheme automatically calculated. You use the classification scheme in an automatic image analysis.

Opening the dialog box

You open this dialog box, by clicking the Automatic Classification button, located in the Define 'One parameter' Classification dialog box. The number of classes and the class limits are adopted from the Define 'One parameter' classification dialog box.

Adopting minimum and maximum values from the image

Click the Get Min/Max from image button. The lowest value of the chosen parameter that is detected on the image will be automatically adopted in the Minimum field. The value is rounded down. If, for example, the smallest measured value is 0.74, the lower classification limit will be 0.73. The highest value detected will be adopted in the Maximum field. The value for the upper classification limit will be rounded down so that the highest measured value itself won't belong to the class. In this way, the bottom limit will become the smallest class, and the upper limit, the largest class, irregardless of the number of classes.

These values can be adopted as they are, or can be altered. You can, at any time, restore the minimum and maximum values from the image, by clicking the Get Min/Max from Image button again.

Prerequisite: The Get Min/Max from Image button only becomes available when an image is loaded and an image analysis has been carried out on the active image.

Determining the number of classes

In the Number of classes field, enter how many classes you want to divide the objects into. The value range for the individual class will be calculated correspondingly.

In the Scale field, choose whether the value range is to be calculated linearly or logarithmically.

Finalizing the class definition

Click OK to have the classes and the corresponding value ranges, adopted in the Define 'One parameter' Classification dialog box.