class ChunkyPNG::Palette

def determine_bit_depth

Returns:
  • (Integer) - Number of bits per pixel, i.e. 1, 2, 4 or 8, or nil if 
def determine_bit_depth
  case size
  when 1..2 then 1
  when 3..4 then 2
  when 5..16 then 4
  when 17..256 then 8
  else nil
  end
end