at the moment I get black screen with the play buttom, i want to have a picture preview frm the video

I'm afraid that this in not supported from the plugin's functionality.

I found it is supported
I wrote this codebut I get error
Plase help

I'm afraid that this in not supported from the plugin's functionality.

 Is this really true?! There is really absolutely no way to see a frame of video in
the video box instead of black?
 
  I would like to have a gallery of videos, but it would look pretty dumb
if the thumbnails are all black.

  Are there other plugins or modules that might have this feature?

thank you!!