This search engine does the same thing but with videos and any associated thumbnails taken from a video. It is important to look out for "scrapes": old videos that are re-uploaded. YouTube doesn't make this information accessible from their website.
NOW WHAT? Well, what information did you find? The creator? The site of original appearance? A different version of the image or video?
DON'T use a video or image if:
Your research leads you to discover the video or image was modified
You can't find enough information to create a proper citation
The creator or source of video or image is NOT affiliated with a mid-level or highly authoritative organization such as:
a university
an academic/scholarly database
a newspaper or other journalism source
a well-edited wiki site that has a reference section