Fade

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FadeIn(clip clip, int num_frames [, int color] [, float fps])
FadeIO(clip clip, int num_frames [, int color] [, float fps])
FadeOut(clip clip, int num_frames [, int color] [, float fps])

FadeIn0(clip clip, int num_frames [, int color] [, float fps])
FadeIO0(clip clip, int num_frames [, int color] [, float fps])
FadeOut0(clip clip, int num_frames [, int color] [, float fps])

FadeIn2(clip clip, int num_frames [, int color] [, float fps])
FadeIO2(clip clip, int num_frames [, int color] [, float fps])
FadeOut2(clip clip, int num_frames [, int color] [, float fps])

FadeOut and FadeOut2 cause the video stream to fade linearly to black or the specified RGB color at the end. Similarly FadeIn and FadeIn2 cause the video stream to fade linearly to black or the specified RGB color at the start when watching the clip backwards. FadeIO and FadeIO2 are a combination of their respective FadeIn and FadeOut functions. The sound track (if present) also fades linearly to or from silence. The fading affects only the last num_frames frames of the video. The last frame of the video becomes almost-but-not-quite black (or the specified color). An additional perfectly black (or the specified color) frame is added at the end, thus increasing the total frame count by one.

FadeOut2 works similarly, except that two black (or color) frames are added at the end instead of one. The only purpose of this is to work around a bug in Windows Media Player. All the WMP versions that I've tested fail to play the last frame of an MPEG file--instead, they stop on the next-to-last frame when playback ends. This leaves an unsightly almost-but-not-quite-black frame showing on the screen when the movie ends if you use FadeOut. FadeOut2 avoids this problem.

The color parameter is optional, default=0 <black>, and is specified as an RGB value regardless of whether the clip format is RGB or YUV based. See Colors (...) for more information on specifying colors.

The fps parameter is optional, default=24.0, and provides a reference for num_frames in audio only clips. It is ignored if a video stream is present. Set fps=AudioRate() if sample exact audio positioning is required.

FadeOut(clip, n) is just a shorthand for Dissolve(clip, Blackness(clip, n+1,color=color), n) (or n+2 instead of n+1 for FadeOut2 and n for FadeOut0).

Changes:

v2.56 FadeIn0/FadeIO0 /FadeOut0 commands are added and the fps parameter is added to all fade functions.
v2.07 Added FadeIO/FadeIO2 commands. Added color parameter to all fade functions.
v2.06 Till v2.06 the FadeIn/FadeIn2 commands do not exist, but you can get the same effect by reversing the arguments to Dissolve: Dissolve(Blackness(clip, n+1, color=color), clip, n).