A fast way to split both a video and its subtitle then integrate the subtitle back into the new segment
(sometimes you may encounter a weird behavious where the output video starts before 5 seconds than specified in the -ss parameter)
ffmpeg -ss 00:00:14.500 -i input.mp4 -t 00:17:05.500 -c copy d:\_ffmpeg_output\output.mp4
ffmpeg -ss 00:00:14.500 -copyts -i input.mp4 -to 00:17:20.0 -c copy d:\_ffmpeg_output\output.mp4
ffmpeg -ss 00:00:14.500 -i input.srt -t 00:17:05.500 d:\_ffmpeg_output\output.srt
ffmpeg -i output003.mp4 -i output003.srt -c copy -c:s mov_text -metadata:s:s:0 language=eng ouptut_soft.mp4
ffmpeg -i subtitle.srt d:\_ffmpeg_output\subtitle.ass
ffmpeg -ss 00:17:15.0 -i subtitle.ass -t 00:15:18.0 d:\_ffmpeg_output\part001-sub.ass
ffmpeg -sub_charenc WINDOWS-1256 -i subtitle.srt d:\_ffmpeg_output\output_win.ass