Size Projection Algorithm: Optimal Thresholding Value Selection for Image Segmentation of Electrical Impedance Tomography

Algorithm 1

The golden-section search method for minimising projection error function.

	Step 0: Let be a grey-scale image to be segmented, and let be a vector of measured boundary voltages.
	Let initial search interval as , and initial step number .
	Set the minimum convergence error and the maximum search steps as .
	Calculate initial testing points: .
	Calculate the projection error , by following equations (3)∼(5).
	Step 1: If , go to Step 2; otherwise, go to Step 3.
	Step 2: If , stop and export ; otherwise, compute the following equations:
	, , , ,
	.
	Calculate projection error , and let , then go to Step 1.
	Step 3: If , stop and export ; otherwise, compute the following equations:
	, , , ,
	.
	Calculate projection error , and let , then go to Step 1.