mlib_ImageColorHSL2RGB(3MLIB)				    mediaLib Library Functions				     mlib_ImageColorHSL2RGB(3MLIB)

NAME

       mlib_ImageColorHSL2RGB - HSL to RGB color conversion

SYNOPSIS

       cc [ flag... ] file... -lmlib [ library... ]
       #include <mlib.h>

       mlib_status mlib_ImageColorHSL2RGB(mlib_image *dst, const mlib_image *src);

DESCRIPTION

       The  mlib_ImageColorHSL2RGB()  function	performs  a conversion from hue/saturation/lightness to red/green/blue. The source and destination
       images must be three-channel images.

       It uses the following equations:

	    L' = L	    if L <= 1/2
	    L' = 1 - L	    if L > 1/2

	     V = L + S*L'
	     P = L - S*L'
	     Q = L + S*L'*(1 - 2*fraction(H*6))
	     T = L - S*L'*(1 - 2*fraction(H*6))

       R, G, B = V, T, P    if 0   <= H < 1/6
       R, G, B = Q, V, P    if 1/6 <= H < 2/6
       R, G, B = P, V, T    if 2/6 <= H < 3/6
       R, G, B = P, Q, V    if 3/6 <= H < 4/6
       R, G, B = T, P, V    if 4/6 <= H < 5/6
       R, G, B = V, P, Q    if 5/6 <= H < 1

       where 0 <= H < 1 and 0 <= S, L, L', V, P, Q, T, R, G, B <= 1.

       Assuming a pixel in the source image is (h, s, l) and its corresponding pixel in the destination image is (r, g,  b),  then  for  MLIB_BYTE
       images, the following applies:

	  H = h/256
	  S = s/255
	  L = l/255
	  r = R*255
	  g = G*255
	  b = B*255

       for MLIB_SHORT images, the following applies:

	  H = (h + 32768)/65536
	  S = (s + 32768)/65535
	  L = (l + 32768)/65535
	  r = R*65535 - 32768
	  g = G*65535 - 32768
	  b = B*65535 - 32768

       for MLIB_USHORT images, the following applies:

	  H = h/65536
	  S = s/65535
	  L = l/65535
	  r = R*65535
	  g = G*65535
	  b = B*65535

       and for MLIB_INT images, the following applies:

	  H = (h + 2147483648)/4294967296
	  S = (s + 2147483648)/4294967295
	  L = (l + 2147483648)/4294967295
	  r = R*4294967295 - 2147483648
	  g = G*4294967295 - 2147483648
	  b = B*4294967295 - 2147483648

PARAMETERS

       The function takes the following arguments:

       dst	       Pointer to destination image.

       src	       Pointer to source image.

RETURN VALUES

       The function returns MLIB_SUCCESS if successful. Otherwise it returns MLIB_FAILURE.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       mlib_ImageColorHSL2RGB_Fp(3MLIB), mlib_ImageColorRGB2HSL(3MLIB), mlib_ImageColorRGB2HSL_Fp(3MLIB), attributes(5)

SunOS 5.10							    10 Nov 2004 				     mlib_ImageColorHSL2RGB(3MLIB)