For the video part, there’s really nothing special. check the following configs/commands for reference:
mod_imagick
<action application="playback" data="{img_ms=60000}imgk:///video/transformer.gif"/>
<action application="playback" data="{img_ms=90000}/video/snake.gif"/>
<action application="playback" data="/video/demo.png"/>
play pdf in conference and seek to pages
conference 3000 play /tmp/demo.pdf
conference 3000 file_seek +1
conference 3000 file_seek +2
Thanks everyone.