I don't know why I didn't figure this out sooner.
This evening, I've been going through a video and looking for cited sources. It used to be that I would just pause, type up the title of the displayed document into a search engine, and grab the citation information on it.
What I've been doing differently tonight is that I've been going through the video and taking screen prints of the sources. And instead of saving them as individual images, I've been pasting the images into a blank slide in a PowerPoint document. The images show the progress bar and the time stamps of the video, so there's additional info in the images.
The beauty of the PowerPoint document is that it has a Notes mode where more can be written about the image as well as complete citation information for the video where I found the information.
Speaking of which, recording the complete citation information of sources has been a God-send on my own research project site. I have been able to use citation information to locate mirrored copies of videos on other cites when they have been deleted.