Initially, Color QuickDraw was only capable of operating with 1, 2, 4 and 8-bit video cards, which were all that was available at the time. Soon after however, 24-bit video cards appeared (so-called true color), and QuickDraw was updated again to support up to 32 bits per pixel (in reality, 24 bits, with 8 unused) of color data ("32-Bit QuickDraw"). The architecture always allowed for this, however, so no new APIs were necessary. The color data structures themselves allowed a color depth of 1, 2, 4, 8, 15 and 24 bits, yielding 2, 4, 16, 256, 32,768 and 16,777,216 colors respectively, or 4, 16 and 256 scales of grey. QuickDraw took care of managing the resampling of colors to the available color depths of the actual video hardware, or transfer between offscreen image buffers, including optionally dithering images down to a lower depth to improve image quality. A set of color sampling utilities were also added so that programmers could generate optimal color palettes for use with indexed video devices.