sentences:  A related capability is the posterization artistic effect, which also reduces the number of colors represented in an image.The difference between this and standard color quantization is that while in standard quantization the final palette is selected based upon a weighting of the prominence of existing colors in the image, posterization creates a palette of colors smoothly distributed across the spectrum represented in the image.Whereas with standard color quantization all of the final color values are ones that were in the original image, the color values in a posterized image may not have been present in the original image but are in between the original color values.