# Relative Soft Thresholding

In addition to specifying a hard binary threshold in terms of a percentage of the pixels in the image (after excluding tail pixels), you can also specify a soft threshold using relative values.

To specify a relative soft binary threshold, you need to supply the following values:

- The percentage of low tail and high tail pixels to exclude
- The percentage value to use for the low threshold
- The percentage value to use for the high threshold
- The number of softness steps.

The tool computes a low and high threshold value using the same procedure described in the section Relative Hard Thresholding. The percentage of low and high tail values specified by the tail percentages are discarded and the pixel values the specified percentages of the distance between the remaining low and high values are used as the low and high threshold values, as shown:

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Once the tool has computed the low and high threshold values, it applies a soft binary threshold as described in the section Soft Thresholding and Pixel Weighting.