Determines the number of colors in the exported chart. A chart that is saved under any depth
will have a minimum of the number of colors that are actually used and a maximum of the number of
colors that are allowed by the depth. For example, if the chart contains three colors (red, white,
and black) and you save it as 16 colors, the chart will remain as three colors.Note: If the number
of colors in the chart exceeds the number of colors for that depth, the colors will be dithered to
replicate the colors in the chart.