View Source ExTDLib.Object.InputStoryContentVideo (ExTDLib v0.0.4)

A video story.

Name	Type	Description
video	InputFile	Video to be sent. The video size must be 720x1280. The video must be streamable and stored in MPEG4 format, after encoding with x265 codec and key frames added each second.
added_sticker_file_ids	number	File identifiers of the stickers added to the video, if applicable.
duration	double	Precise duration of the video, in seconds; 0-60.
is_animation	bool	True, if the video has no sound.

More details on telegram's documentation.