What's the name of this graphic illustration technique?

Factual Questions
1

Is there a standard industry term for this technique in graphic illustration?:

There’s a photo of the Sgt. Pepper’s Lonely Hearts Club Band album cover; underneath is a sort-of reproduction of the photo showing only outlines of the characters with numbers in their heads; underneath is an identifying list that matches numbers with characters.

Examples:

Sgt. Pepper:

Particularly helpful–Bob and Ray:
http://www.bobandray.com/albums/classic1.html

Is this called a photo-silhouette index or something like that?

2

I’ve heard it called a “photo legend” or a “picture legend,” but that’s not necessarily confined to one particular technique. (But for a group photo, it’s usually either silhouettes or outlines.)