SPIDER: IA (Interface Area)

IA - Interface Area

(08/08/08)

PURPOSE: Computes the interfacial area between pixels/voxels having intensities that are at or above a solicited threshold and pixels/voxels having intensities below the threshold. Works for both images and volumes. Example.

SEE ALSO

FV	[Find threshold for Volume]

USAGE

.OPERATION: IA [ntotal],[nabove],[iarea]

[Find interfacial area. This operation can return up to 3 optional register variables which contain:

Variable	Example	Receives
First	[ntotal]	Total number of pixels/voxels
Second	[nabove]	Number of pixels/voxels at or above threshold
Third	[iarea]	Interface area

.INPUT FILE: PIC001
[Enter the name of the image or volume.]

.THRESHOLD LEVEL: 1.0
[Threshold for counting interfaces.]

NOTES

Voxels/pixels at the boundaries of the image/volume that are at-or-above the threshold will have a surface counted at the boundary.
Interface area is a count of the number of interfaces. In 3D this is a count of number of square surfaces present at an interface.