Threshold: Image Thresholding & Binary Mask (Otsu, RGB)

Threshold

This function performs a segmentation based on the definition of a brightness range (separated according to color channels (red, green, blue)) for the regions to be segmented. All pixels whose color values lie within the defined color range are marked as region pixels in the resulting image. All the pixels whose color values lie outside the defined color range are marked as background pixels (black).

In the resulting image, the color values of the region pixels can either be set permanently to white or adopted unchanged. If you set the region pixels permanently to white, the result is a binary image, which can then be used as a mask image for a subsequent automatic measurement.

Parameter		Description
Method		Only visible if Show All is activated.
-	Otsu	For all possible threshold values, the Otsu method calculates the variance of intensities on each side of the respective threshold. It minimizes the sum of the variances for the background and the foreground.
-	Maximum Peak	Separates background and foreground pixels at the maximum value of the histogram.
-	Iso Data	The threshold value lies in the middle between two maximums in the histogram.
-	Triangle Threshold	The threshold value is calculated from the sum of the average and three times the sigma value of the histogram distribution.
-	Three Sigma Threshold
Level Low		Determines the lower brightness threshold for the regions to be segmented. All the pixels whose gray values lie below this threshold value are marked as background pixels (black).
Level High		Determines the upper brightness threshold for the regions to be segmented. All the pixels whose gray values lie above this threshold value are marked as background pixels (black).

The following parameters are only visible if the Show All mode is activated:

Parameter	Description
Create Binary	Activated: The resulting image is a binary image. Pixels within the calculated gray level range are set to the maximum gray value (white), whilst pixels outside it are set to the gray value 0. Deactivated: The resulting image is of the same type as the input image. Pixels within the calculated gray level range are set to the original gray value. Pixels outside it are set to 0.
Invert Result	Activated: Inverts the effect of the function. The segmented regions will be given the value 0, and all other pixels the gray value white or the gray value/color of the input image.

Parameter

Description

Create Binary

Activated: The resulting image is a binary image. Pixels within the calculated gray level range are set to the maximum gray value (white), whilst pixels outside it are set to the gray value 0.

Deactivated: The resulting image is of the same type as the input image. Pixels within the calculated gray level range are set to the original gray value. Pixels outside it are set to 0.

Invert Result

Activated: Inverts the effect of the function. The segmented regions will be given the value 0, and all other pixels the gray value white or the gray value/color of the input image.