The solid color is either solid black in the left half of the image or full-on color (red, green or blue) in the right half of the image.
The left and right bands are divided up into ten-pixel-high blocks. Each block is a solid color that is one 1/256 brighter than the previous block. These blocks are separated by a contrasting line to make it easier to distinguish them. Note that the left and right bands are both the same color dispite some minor optical illusions due to the the contrasting lines.
The striped part is made up of one pixel-high bands alternating between solid black and full-on color. When viewed from a distance or when squinting, this provides a reference point against which we will attempt to calibrate the 50% intensity colors.
