ELI5: Explain Like I'm 5

Difference matte

OK kiddo, so imagine you have two pictures: one is a picture of you sitting in your room and the other is a picture of your room without you in it.

Now, we want to find out what's different between these two pictures. We could look at each picture carefully and try to find the differences, but that would take a long time and be really hard.

That's where a "difference matte" comes in! It's like magic paper that shows us exactly what's different between the two pictures.

First, we put the two pictures into a special computer program. Then, the program puts a big grid over both pictures, kind of like a checkerboard.

Next, the program looks at each square on the grid, and compares the color in that square between the two pictures. If the color is exactly the same in both pictures, the square stays black. But if the color is different, the square turns white.

Once the program has compared every square on the grid, we end up with a new picture that shows us all the differences between the two pictures.

This new picture is called a "difference matte". We can use it to see exactly where you were sitting in your room, because all the squares where you were sitting are black, and all the squares where you weren't sitting are white.

Pretty cool, huh? The difference matte is a really handy tool for finding differences between pictures, and it saves a lot of time compared to looking at each picture one by one.