此命令用于创建fad in和fad out:
https://androidlearnersite.wordpress.com/2017/03/17/ffmpeg-video-editor/comment-page-1/#comment-150
String[] command = {"-y", "-i", file.getAbsolutePath(), "-acodec", "copy",
"-vf", "fade=t=in:st=0:d=5,fade=t=out:st=" +
String.valueOf((Share.size_of_images * 3sec) - 5) + ":d=5",
file1.getAbsolutePath()};
video path = file.getAbsolutePath()
output path = file2.getAbsolutepath()
厌倦了创造这个。 请帮帮我。