PCA Color Projection
Projecting RGB colors to one or two dimensions.
When projecting to one dimension, RGB colors become gray scale. Projecting to Principal Component 1 will preserve the most features because it has the most variance. Principal Component 3 will have the smallest variance and therefore preserve the fewest amount of features.
Projecting to two principal components will remove one color (Red, Green, or Blue) and only assign values to two of them. In the example below, values are projected to green and blue only when two principal components are used. Another version could assign values differently for the two principal components.