Table 3.

Performance of noise reduction techniques evaluatedusing spot efficiency

Noise type	Noise reduction technique	Noise intensity (dB)
		20	18	16	14	12	10	8
Gaussian	Wavelet	90.71	90.00	90.36	87.86	88.57	86.07	71.79
	Contourlet	89.29	88.57	87.50	87.51	78.93	65.00	44.64
	TV	87.14	89.64	86.79	85.00	72.21	37.89	25.12
	WVTV	87.14	86.43	86.43	85.71	86.79	87.14	85.16
Rayleigh	Wavelet	90.36	89.64	89.64	91.43	89.64	87.86	88.57
	Contourlet	89.64	88.57	88.57	86.07	89.29	84.64	72.36
	TV	87.86	87.86	85.36	88.57	85.43	87.59	51.25
	WVTV	86.43	86.79	87.86	85.00	86.79	86.07	83.57
Exponential	Wavelet	90.00	90.00	88.93	88.21	88.21	88.21	77.14
	Contourlet	90.36	87.14	87.86	84.29	72.50	61.84	48.25
	TV	90.71	89.29	87.50	86.07	82.86	75.00	62.37
	WVTV	85.71	85.36	85.36	85.71	84.29	85.57	83.93

Note: TV, total variation; WVTV, wavelet-total variation. The values in bold indicate the best spot efficiency for each noise level.