CONTRASTZOOM
The purpose of this program is to demonstrate how to zoom an image "in place" and how to window and level (set "contrast and brightness") an image using object graphics functionality. The exercise involves using multiple views in an object graphics scene, and being able to interact with different views in different ways.
FANNING SOFTWARE CONSULTING David Fanning, Ph.D. 1645 Sheely Drive Fort Collins, CO 80526 USA Phone: 970-221-0438 E-mail: david@idlcoyote.com Coyote's Guide to IDL Programming: http://www.idlcoyote.com
Widgets, Object Graphics.
ContrastZoom, image
None. The image "mr_knee.dcm" from the examples/data directory is used if no data is supplied in call.
image: A 2D image array of any data type.
COLORTABLE: The number of a color table to use as the image palette. Color table 0 (grayscale) is used as a default. GROUP_LEADER: The group leader for this program. When the group leader is destroyed, this program will be destroyed.
None.
None.
None. The Coyote Library program VCOLORBAR is included.
To use this program with your 8-bit image data and a red-temperature color scale, type: IDL> ContrastZoom, image, Colortable=3
The left image is used to "zoom" into a portion of the image. The aspect ratio of the sub-image is always preserved. To see the entire image, click and release the mouse button in this window. The center image is used to adjust the contrast and brightness (sometimes called the "window" and "level" of the image. Click and drag the mouse vertically to set contrast. Click and drag the mouse horizontally to set brightness. To return to original values (25% contrast and 75% brightness), click and release in the center image. The color bars shows the image values of the image.
Written by David Fanning, 18 November 2001. Added second colorbar to show the relationship of the clamped colors to the overall image values. 19 November 2001. DWF. Changed FSC_Normalize to cgNormalize to reflect new name. 6 Feb 2013. DWF.