Noise
Let's understand the concept of noise in detail. In the field of signal processing, noise is simply just any unwanted signal mixed in with the expected signal. When we talk in terms of noise in images or videos, we can define noise as the undesired variation of intensity and color of pixels. This noise can come from multiple sources.
A few examples include dust on a camera lens, grains in the photo film (this one is desired in analog photography and filmmaking), errors in the CCD sensor and its storage, errors during transmission and reception, and errors while scanning the photograph. A very high amount of noise is not desired. This is because high noise reduces the useful and expected signal, affecting the quality of images.
We can mathematically represent the signal-to-noise ratio with the following formula:
Note:
A higher signal-to-noise ratio means a better quality regarding the signal and the image.
