Mean filtering is an easy-to-understand and -implement technique for smoothing pictures by minimising the intensity differences between neighbouring pixels. It's a common method for cleaning up pixelated photos.
This is a non-linear filter that uses the function cv2.medianBlur() in OpenCV to calculate the median of all the pixels under the kernel region and replace the element with this value
The amplitude of a wavelet starts at zero, grows or shrinks, and then cycles back to zero one or more times. [1]
The Restormer is pre trained model for picture denoising.
[1] "Wavelet" https://en.wikipedia.org/wiki/Wavelet