Default Transfer Function Properties

Profile [|>]

Selects the parameter profile for this command and allows you to save or work with existing presets.

Scaling Properties

The properties in this group determine the type of transfer function based on image intensity values.

Sample

The Sample control determines the region where the image intensity is sampled for calculating the transfer function. The options are as follows:

Full Image: Samples the entire image.

Cursor: Samples the region inside the Image Cursor.

Cursor Live: Samples the region inside the Image Cursor and updates as the cursor moves. This slows cursor movement.

Range

The Range specifies how the intensity limits are calculated from the sample region. One of the options allows you to force the minimum and maximum to specific values.

Stretch

The Stretch provides options for extending the transfer function to higher or lower intensity. The options are as follows:

Linear: Uses no Bias with equal Grayscale spacing between the transfer function's limiting values.

Log: Extends the transfer function to greater contrast at lower intensity values.

Gamma: Extends the transfer function to higher or lower intensity based on the gamma setting. A gamma less than 1 biases toward higher contrast in lower intensity, and vice versa.

 Boost

Check this box to selectively boost the contrast using a proprietary algorithm that enhances contrast between pixel values crowded in a narrow range of value, usually near the background level. This works with intensity images but not with RGB images. This feature was added to Mira Pro x64 version 8.66.

Gamma Slider

Sets the gamma value when Gamma Stretch is selected.

Min Z

Specifies the minimum Z (intensity) value. This is active only when the Specify Z Stretch is selected.

Max Z

Specifies the maximum Z (intensity) value. This is active only when the Specify Z Stretch is selected.

Sample Region Properties

The properties in this group define the rectangle containing pixels for computing the transfer function. These values are set to a percentage of the image dimensions:

Column Offset %

Specifies the column offset to the center for the sampling rectangle as a percentage of the image width (column count). For example, a value of 50 sets the center of the rectangle to 50% of the image width, or the central column of the image.

Column Extent %

Specifies the width of the sampling rectangle as a percentage of the image width (column count). For example, a value of 80 sets the rectangle width to 80% of the image width.

Row Offset %

Specifies the row offset to the center for the sampling rectangle as a percentage of the image height (row count). For example, a value of 50 sets the center of the rectangle to 50% of the image height, or the central row of the image.

Row Extent %

Specifies the height of the sampling rectangle as a percentage of the image height (row count). For example, a value of 80 sets the rectangle height to 80% of the image height.

Default

Sets the sampling region to the center of the image (50%) with a rectangle spanning 80% of the image dimensions. This is the Mira default at installation time.

Contrast

Specifies the contrast value when the Autoscale Stretch is selected.