Noise Reduction

We implemented four noise-reduction algorithms.

• Mean smoothing [9] by a 3x3 or 5x5 convolution kernel.
• A median [8] filter replaces a pixel by the median value of its neighborhood.
• Gaussian smoothing [11] implemented by using discrete 3x3 and 5x5 convolution kernels.
• The ``Mean & Median'' [6] button: Pixel values in a 3x3 neighborhood excluding salt-pepper noise are averaged together.