Adaptive Bilateral Filter for Sharpness Enhancement and Noise Removal

Restoration for weakly blurred and strongly noisy images

“…Several leading adaptive sharpening approaches (Adaptive UM [11], Constrained UM [2] and ABF [18]) are also applied as comparison.…”

“…However, linear unsharp masking is very sensitive to noise and can easily produce overshoot artifacts [11]. Several adaptive versions of unsharp masking have been proposed to alleviate these problems [11,12,6,18,2]. In [11] the scaling factor that controls sharpening strength is determined according to local image characteristics measured by "image activity".…”

“…Meanwhile the clipping process may affect structure smoothness generating artifacts especially for heavily noisy regions. Another sharpening algorithm called adaptive bilateral filter (ABF) can achieve good noise suppression [18]. ABF was designed by introducing an offset into the bilateral filter, which switches the behavior of the filter from denoising to edge sharpening according to local image structure.…”

The Study of Phase-Based Optical Flow Technique Using an Adaptive Bilateral Filter

“…This ensures that averaging is performed along the boundary area and is significantly decreased in the gradient direction. For this reason, the bilateral filter can suppress the noise while at the same time preserving contour areas [18]. Consequently, the bilateral filter performs as a standard domain filter, and eliminates the weakly correlated differences between pixel values caused by noise.…”

“…The bilateral filter is the one of the most suitable solutions to cope this problem [16]. Bilateral filtering is defined as a non-linear filtering technique which utilizes both spatial and amplitudinal distances to better preserve the boundary information [15], [17], [18].…”