Activity 18: Noise model and basic image restoration

In this activity we explore the different type of image noise and try some techniques for cleaning them. I applied 5 types of noise: impulse, uniform, exponential, gamma and gaussian. I then implemented 4 methods of noise removal: harmonic, geometric, contraharmonic and arithmetic. Here are the results:

Original image

From top to bottom:
salt and pepper / uniform / exponential / gamma / gaussian
From left to right:
arithmetic / contraharmonic / geometric / harmonic / noise only

The images get darker/brighter because I normalized them after adding the noise. For most types of noise, the arithmetic restoration yields the best results. Also, the other methods which rely on multiplication fail at places where the noise peak.

I give myself 8/10 because i wasn't able to implement the Rayleigh noise.