Performing some kind of non-linear filters on images often induces aliasing, this program implements the method described in this paper which helps to recover images damaged by some kind of non-linear filters. It is performed as an adjustment of gradients in some regions that were potentially damaged in the filtered image.

This project uses cmake.

Download and install CMake if you don't already have it. To simplify installation you may use Homebrew:

brew install cmake

sudo apt-get install cmake

Images should be PPM format 24 bits. The program is looking for images from the media/ folder which should be located in the working directory.

./aarecovery.out -o original [-f filtered] # filenames without extension

The following images were zoomed to assess the results.

Original image:

Non-linear filter performed on it (here simple thresholding):

The result of performing anti-aliasing recovery: