Grayscale Look-Up Tables

The ImageGear display API allows storing a grayscale (single-channel) look-up table (LUT) with an image's display settings. The grayscale look-up table can be set for any image, but ImageGear only uses it with 8...16-bit grayscale images, and ignores it with the other images. This look-up table specifies a transform from 16-bit image to 8-bit image, which allows the display of a particular part of an 8...16-bit image's contrast range, or enhanced image's contrast.

A grayscale LUT can be stored with a 16g image as well. However, if both the image and its display contain LUTs, the display LUT overrides the image's LUT. A LUT can be removed from an image and attached to a display, or vice versa.

Storing a grayscale LUT with display settings allows you to display the same image with different LUTs simultaneously in different windows.

A grayscale LUT can be used in combination with a RGB LUT. The grayscale LUT is applied first, and then the RGB LUT is applied.

Use IG_dspl_grayscale_LUT_update_from() to create or update a grayscale LUT with the specified LUT. LUT data will be copied to the display settings. Set the lut parameter to NULL to remove the grayscale LUT from display settings.

Use IG_dspl_grayscale_LUT_exists() to check whether display settings contain a grayscale LUT.

Use IG_dspl_grayscale_LUT_copy_get() to obtain a copy of the display grayscale LUT.

The ImageGear Medical Component provides a set of API functions that allow building grayscale LUTs according to various DICOM display settings.

The only allowed LUT configuration for display is: InputDepth = 16, OutputDepth = 8, Output is unsigned. Such LUTs can be used with grayscale images whose depth is 8... 16 bits per pixel.

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