Fade in

Fade in means something comes gradually into view. It is used in the fields of cinema and television. This is normally used when film begins.

The opening of a shot, starting from a tiny point, in the form of an ever-growing circle, until it turns into an image that fills the entire footage.The opposite of punctuated darkening.

In general, artists make a lot of use of fading or fading where a solid background gradually becomes coloured, and they also use it in music productions where a sound is gradually increased, faded or faded to inaudible. You can call sunrise the slowing down of the light and the sunset the dimming of the light.

For more information about the film industry;

https://cinema8.com/blog/5-reasons-for-film-industry-to-use-interactive-videos