BI_BITFIELDS top-level constant
int const BI_BITFIELDS
Specifies that the bitmap is not compressed and that the color masks for the red, green, and blue components of each pixel are specified in the bV5RedMask, bV5GreenMask, and bV5BlueMask members. This is valid when used with 16- and 32-bpp bitmaps.
const BI_BITFIELDS = 3;