fade - FFmpeg 1.2.12 / Filters / Video

Apply fade-in/out effect to input video.

The filter accepts parameters as a list of key=value pairs, separated by ":". If the key of the first options is omitted, the arguments are interpreted according to the syntax type:start_frame:nb_frames.

A description of the accepted parameters follows.

type, t: Specify if the effect type, can be either in for fade-in, or out for a fade-out effect. Default is in.
start_frame, s: Specify the number of the start frame for starting to apply the fade effect. Default is 0.
nb_frames, n: Specify the number of frames for which the fade effect has to last. At the end of the fade-in effect the output video will have the same intensity as the input video, at the end of the fade-out transition the output video will be completely black. Default is 25.
alpha: If set to 1, fade only alpha channel, if one exists on the input. Default value is 0.

Examples

Fade in first 30 frames of video:
```
fade=in:0:30
```
The command above is equivalent to:
```
fade=t=in:s=0:n=30
```
Fade out last 45 frames of a 200-frame video:
```
fade=out:155:45
```
Fade in first 25 frames and fade out last 25 frames of a 1000-frame video:
```
fade=in:0:25, fade=out:975:25
```
Make first 5 frames black, then fade in from frame 5-24:
```
fade=in:5:20
```
Fade in alpha over first 25 frames of video:
```
fade=in:0:25:alpha=1
```