Add visualization crop

[talaon2]

I have a lot of issues to go through, so in order to make it easier for me to help you, I ask that you please try these things first

• Check out all the menus and keyboard shortcuts. Maybe the feature already exists?
• Try with the newest version from GitHub
• Read the documentation and FAQ, Known issues, Troubleshooting to see if the feature already exists
• See if someone already suggested this under Issues or Discussions

Description

There are some messy things on the video, above, below, or elsewhere, which can be dealt with by setting x y w h in ffmpeg crop. We look forward to a visual operation interface. It is best to select by drawing a frame with the mouse.

[mifi]

Duplicate of #643