Thank you for the question.
Descriptive video is the process of adding an audio track to the program so whenever there are pauses in the dialogue the narrator will describe scenes, action, costume changes, whatever is happening on the screen that a non-visually-impaired person would be able to see, for the benefit of those of us who are not able to see what's happening on the screen. Obviously, as I'm sure you can understand, it will greatly assist in providing a better understanding of the movie or the program you're watching.
As a challenge, I would recommend that committee members turn their back to their television for one day and try to watch and report on what they were able to comprehend. How many times do we hear “for more information call the number at the bottom of your screen”? That's all well and good, but as a consumer I don't have access to that number at the bottom of the screen. If I want to see if my stocks are going up, or mainly down, when you look at the stock report that's exactly what you're doing. You're looking at it. You don't get the audible information conveyed to you.
So that's the process. It's to render images in a narrative way so you can follow the programming.