fade-in
US /ˈfeɪd.ɪn/
UK /ˈfeɪd.ɪn/

1.
淡入, 渐显
a gradual increase in the visibility of an image or the volume of a sound in a film, television, or radio production
:
•
The scene began with a slow fade-in of the sunrise.
场景以日出的缓慢淡入开始。
•
We need a smooth fade-in for the background music.
背景音乐需要一个平滑的淡入。