[FFmpeg-user] Understanding the behavior of "-ss/-t" option

[Gyan]

Use

   ffmpeg  -i input_clip_x264_offset.mp4 -copyts -ss 60 -t 10 -filter:v
"select=between(t\,60.000\,70.000)" -c:v libx264 offset_extract.mp4

Looks like -seek_timestamp 1 gets inert when used in conjunction with
copyts.