Commented Unassigned: png after resize() totalcolor will increase [1371]

png after resize() totalcolor will increase

png8
image.totalcolor=32
image.ColorType = ColorType.Palette;

and I after resize(980,0)

it change to
image.totalcolor=213
image.ColorType = ColorType.TrueColor;

This should be a bug
Comments: It is not a bug, this is how ImageMagick works. When you resize an image a filter is used to get the new values for a pixel. And that will increase the number of colors in your image. You can find a good detailed explanation here: http://www.imagemagick.org/Usage/filter/#filter. You can reduce the number of colors with the Quantize method of MagickImage (command line info: http://www.imagemagick.org/Usage/quantize/#intro).