Introduction to color space

- [Instructor] How many different colors can you see? Feels like an endless possibility. Impossible to count them all, right? Well, if we want to represent colors digitally, we have to find a way of counting color. That is, for any given shade you can see, we need to give it a unique number or an address. Because numbers are something both humans and machines can agree on. One simple way we could do this is to give a percentage for each color value. We call this an RGB triple. For example, 100% red plus 100% green plus 100% blue is white. 0% red, 0% green, 0% blue is black. Whereas, 100% red and 100% green, but 0% blue, is yellow. We saw this in lesson one. Mathematicians love to represent things geometrically or spatially, so they came up with the idea of a color space. It's quite simple. Normally, we represent a point in three dimensional space using x, y, and z-coordinates, like this. But, instead, let's rename the axes red, green, and blue. And that gives us this color cube. The key idea is this: every point within this cube represents a specific color a projector or a computer monitor could create. So, remember all those colors you were thinking about? Well, any specific color you're looking at will always be a point in this cube. To help this sink in, we have a color cube exercise that you can play with. Give it a try.