Color Enhancement in Endoscopic Images Using Adaptive Sigmoid Function and Space Variant Color Reproduction

Table 7

Comparisons of focus value with other related works.

Image number	Focus value
	Original	AHE [11]	CLAHE [12]	HBF [13]	BPDFHE [14]	Proposed
1	15.64	17.50	22.96	22.86	22.04	42.10
2	12.52	16.75	20.14	19.33	17.11	42.52
3	18.01	19.20	23.18	22.40	22.00	41.57
4	13.66	18.85	22.01	20.97	20.51	42.00
Average of 60 endoscopic images	13.77	19.08	21.11	20.49	19.49	41.17