Using the Raster for my Background Image

First of all, I made the plugin work so the video has a clean transition with the background image.
That means I took a screenshot from the beginning of the video and put it as a background image inside the theme options (Divi Theme) – after like 2 seconds the video starts appearing but you can’t see the transition because it starts exactly from where the screenshot was taken. Thats exactly what I wanted to achieve.

Also I want to use the raster function for the video. But the problem is that the background image has no raster so the transition gets obvious.

My Question is: How can I use the same raster from the plugin for the background image as well?