A Three-Step Approach with Adaptive Additive Magnitude Selection for the Sharpening of Images

Table 1

Comparisons of the sharpened images with respect to original images in terms of PSNR.

Image	Dimension	Edge sharpening images
		(a) HVD			(a) HVD with			(b) Canny			(b) Canny with			Δ
		Neck	504 × 700	77.938	68.218	63.720	83.028	73.281	68.796	81.480	71.643	67.189	83.704		73.878	69.420	38
Moon surface	256 × 256	70.265	60.698	56.194	75.289	65.728	61.234	75.706	66.163	61.674	79.315	69.764	65.280	41
Gold hill	720 × 576	73.264	63.575	59.054	76.332	66.632	62.104	77.978	68.261	63.742	88.846	79.145	74.616	34
Aerial	256 × 256	57.342	47.837	47.837	57.781	48.276	43.881	62.617	53.076	48.629	63.789	54.240	49.781	43
Chemical plant	256 × 256	67.366	57.742	53.247	69.263	59.638	55.147	68.819	59.155	54.653	70.337	60.679	56.174	38
Grass	512 × 512	67.633	57.979	53.434	69.682	60.028	55.482	69.336	59.706	55.168	70.562	60.930	56.392	31
Finger	512 × 512	60.275	50.685	46.162	61.302	51.712	47.189	63.510	53.933	49.414	64.274	54.697	50.177	39
Pentagon	512 × 512	66.284	56.653	52.128	67.386	57.755	53.231	71.255	61.647	57.142	72.705	63.093	58.586	33
Lena	512 × 512	76.111	66.575	62.161	78.282	68.720	64.268	78.625	69.088	64.676	79.357	69.812	65.393	39

“” is a scaling factor between 0 and 1.