The Image options tab controls how Video Hub handles a video’s thumbnail. Find it under Videos → Settings, on the Image options tab.
Import images
Import the video’s thumbnail into your WordPress media library and set it as the post’s featured image. With this enabled, the image is imported the moment the post is created.
Import featured image on request
With image importing enabled, this delays each image until it’s actually needed: WordPress fetches it the first time it has to display the image, rather than at import time. It’s a good way to take load off the import process, since image processing is resource-heavy.
Image size
Set the maximum thumbnail size to import from YouTube. WordPress still generates all of its registered intermediate sizes regardless of what you choose here.
The companion option — retrieve maximum resolution image — tries to grab a larger version when one exists, overriding the size above. Note that not every video has a maximum-resolution image.