Table 2.

Performance metrics.

Measures	Description
Peak signal to noise ratio (PSNR)	20 log10⁡(MAXI) − 10 log10⁡(MSE)	Measures quality of image.
Sensitivity or true positive rate (TPR)	$\mathrm{T}\mathrm{P}\mathrm{R}=\frac{\mathrm{T}\mathrm{P}}{\mathrm{P}}=\frac{\mathrm{T}\mathrm{P}}{\mathrm{T}\mathrm{P}+\mathrm{F}\mathrm{N}}$	Measures the ratio between TP and FN.
False positive rate (FPR)	$\mathrm{F}\mathrm{P}\mathrm{R}=\frac{\mathrm{F}\mathrm{P}}{\mathrm{N}}=\frac{\mathrm{F}\mathrm{P}}{\mathrm{F}\mathrm{P}+\mathrm{T}\mathrm{N}}=(\mathrm{1}-\mathrm{S}\mathrm{P}\mathrm{C})$	Measures the ratio between FP and TN.
False negative rate (FNR)	$\mathrm{F}\mathrm{N}\mathrm{R}=\frac{\mathrm{F}\mathrm{N}}{\mathrm{T}\mathrm{P}+\mathrm{F}\mathrm{N}}=(\mathrm{1}-\mathrm{T}\mathrm{P}\mathrm{R})$	Measures the ratio between FN and TP.
Specificity (SPC) or true negative rate (TNR)	$\mathrm{S}\mathrm{P}\mathrm{C}=\frac{\mathrm{T}\mathrm{N}}{\mathrm{N}}=\frac{\mathrm{T}\mathrm{N}}{\mathrm{T}\mathrm{N}+\mathrm{F}\mathrm{P}}$	Measures the ratio between TN and FP.
Accuracy (ACC)	$\mathrm{A}\mathrm{C}\mathrm{C}=\frac{(\mathrm{T}\mathrm{P}+\mathrm{T}\mathrm{N})}{\mathrm{T}\mathrm{P}+\mathrm{F}\mathrm{P}+\mathrm{F}\mathrm{N}+\mathrm{T}\mathrm{N}}$	The degree to which the result of a measurement, calculation, or specification confirms the correct value or a standard.
Area under curve (AUC)	A = ∫∞ −∞TPR(T)FPR′(T)dT	How much system is sensitive to detect the desired output?