Multilevel Thresholding Segmentation Based on Harmony Search Optimization

Table 9

Results after appling the HSMA using Kapur’s function to the set of benchmark images.

Image	𝑘	Thresholds 𝑥^𝑐best	PSNR	STD
Camera man	2	128, 196	13.626	3.60𝐸−15
	3	44, 103, 196	14.460	1.40𝐸−03
	4	44, 96, 146, 196	20.153	1.20𝐸−03
	5	24, 60, 98, 146, 196	20.661	2.75𝐸−02
Lena	2	96, 163	14.638	3.60𝐸−15
	3	23, 96, 163	16.218	7.66𝐸−02
	4	23, 80, 125, 173	19.287	1.44𝐸−14
	5	23, 71, 109, 144, 180	21.047	1.22𝐸−02
Baboon	2	79, 143	16.016	1.08𝐸−14
	3	79, 143, 231	16.016	7.19𝐸−02
	4	44, 98, 152, 231	18.485	8.47𝐸−02
	5	33, 74, 114, 159, 231	20.507	1.08𝐸−14
Hunter	2	92, 179	15.206	1.44𝐸−14
	3	59, 117, 179	18.500	4.16𝐸−04
	4	44, 89, 133, 179	21.065	4.31𝐸−04
	5	44, 89, 133, 179, 222	21.086	3.43𝐸−02
Airplane	2	70, 171	15.758	3.30𝐸−03
	3	68, 126, 182	18.810	1.08𝐸−14
	4	68, 126, 182, 232	18.810	1.82𝐸−01
	5	64, 104, 143, 184, 232	20.321	1.80𝐸−01
Peppers	2	66, 143	16.265	7.21𝐸−15
	3	62, 112, 162	18.367	1.80𝐸−14
	4	62, 112, 162, 227	18.376	2.39𝐸−02
	5	48, 86, 127, 171, 227	18.827	4.17𝐸−04
Living room	2	89, 170	14.631	1.40𝐸−03
	3	47, 103, 175	17.146	2.70𝐸−03
	4	47, 98, 149, 197	19.144	1.34𝐸−02
	5	42, 85, 125, 162, 197	21.160	1.89𝐸−02
Blonde	2	125, 203	12.244	1.44𝐸−14
	3	65, 134, 203	16.878	1.00𝐸−03
	4	65, 113, 155, 203	20.107	5.50𝐸−03
	5	65, 113, 155, 203, 229	20.107	4.48𝐸−02
Bridge	2	94, 171	13.529	7.40𝐸−03
	3	65, 131, 195	16.806	1.44𝐸−02
	4	53, 102, 151, 199	18.902	2.47𝐸−02
	5	40, 85, 131, 171, 211	20.268	2.12𝐸−02
Butterfly	2	27, 213	8.1930	2.25𝐸−02
	3	27, 120, 213	13.415	8.60𝐸−04
	4	27, 96, 144, 213	16.725	3.80𝐸−03
	5	27, 83, 118, 152, 213	19.413	3.90𝐸−03
Lake	2	91, 163	14.713	1.44𝐸−14
	3	73, 120, 170	16.441	3.05𝐸−04
	4	69, 112, 156, 195	17.455	4.53𝐸−02
	5	62, 96, 131, 166, 198	18.774	3.66𝐸−02