Spatial Filtering Spatial Filtering Methods or Mask Processing
Finest image sharpening by use of the modified mask filter dealing with highest spatial frequencies - ScienceDirect
Photoshop: Smarter sharpening with the High Pass filter
Is Unsharp Mask (USM) Equivalent to Applying Laplacian of Gaussian Filter Directly on the Image? - Signal Processing Stack Exchange
Photoshop Sharpening for Beginners – Unsharp Mask, High Pass and Smart Sharpen Explained
Sharpen Images in Photoshop with the High Pass filter
High Boost filtering In image processing, it is often desirable to emphasize high frequency components representing the image details without eliminating. - ppt download