Video noise is identifiable by a rapidly changing, grainy pattern that is noticeable from one frame to the next. It's easiest to understand through real-life examples: Noise typically emerges in low-light conditions such as at night, during dusk, indoors, or on cloudy days. Cameras of higher quality and price generally produce videos with less noise, thanks to their larger sensors and bigger lenses which allow more light to enter.
Conversely, mobile devices, which tend to have smaller and less expensive sensors, are more prone to noise issues, especially in less-than-ideal lighting (like indoors or on overcast days). A clear example of this can be seen by zooming into a photo taken indoors with a smartphone, where the noise becomes more apparent.
When to apply Noise reduction AI filter?
To determine if your video has noise, simply play it in your preferred video player. If you notice a fine, buzzing pattern in the footage, it's a good indication that applying a noise reduction filter would be beneficial.
Noise vs Grain
Noise and grain may appear similar but are caused by different factors. Grain is often present in older film tape formats such as 32mm, 16mm, and 8mm. It contributes to the unique 'film look' of movies and is generally considered a desirable attribute.
On the other hand, noise occurs due to disturbances in the camera signal and is typically unwanted in videos/images. Noise can have color, whereas grain is usually monochromatic.
In the provided image, the left side displays grain, while the right side shows digital noise. You can distinctly see that the noise contains color, contrasting with the colorless grain.