Content-type: text/html Man page of mlib_ImageColorRGB2HSV

mlib_ImageColorRGB2HSV

Section: mediaLib Library Functions (3MLIB)
Updated: 2 Mar 2007
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NAME

mlib_ImageColorRGB2HSV - RGB to HSV color conversion  

SYNOPSIS

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

mlib_status mlib_ImageColorRGB2HSV(mlib_image *dst, const mlib_image *src);

 

DESCRIPTION

The mlib_ImageColorRGB2HSV() function performs a conversion from red/green/blue to hue/saturation/value. The source and destination images must be three-channel images.

It uses the following equations:

   V = max(R, G, B)
Vmin = min(R, G, B)

  S = (V - Vmin)/V

  H = (5.0 + (V - B)/(V - Vmin))/6  if R = V and G = Vmin
  H = (1.0 - (V - G)/(V - Vmin))/6  if R = V and B = Vmin
  H = (1.0 + (V - R)/(V - Vmin))/6  if G = V and B = Vmin
  H = (3.0 - (V - B)/(V - Vmin))/6  if G = V and R = Vmin
  H = (3.0 + (V - G)/(V - Vmin))/6  if B = V and R = Vmin
  H = (5.0 - (V - R)/(V - Vmin))/6  if B = V and G = Vmin
  H = 0.0                           if R = G = B

where 0 ≤ R, G, B, V, Vmin, S ≤ 1 and 0 ≤ H < 1.

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

   R = r/255
  G = g/255
  B = b/255
  h = H*256
  s = S*255
  v = V*255

for MLIB_SHORT images, the following applies:

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

for MLIB_USHORT images, the following applies:

   R = r/65535
  G = g/65535
  B = b/65535
  h = H*65536
  s = S*65535
  v = V*65535

and for MLIB_INT images, the following applies:

   R = (r + 2147483648)/4294967295
  G = (g + 2147483648)/4294967295
  B = (b + 2147483648)/4294967295
  h = H*4294967296 - 2147483648
  s = S*4294967295 - 2147483648
  v = V*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 TYPEATTRIBUTE VALUE

Interface StabilityCommitted

MT-Level

 

SEE ALSO

mlib_ImageColorHSV2RGB(3MLIB), mlib_ImageColorHSV2RGB_Fp(3MLIB), mlib_ImageColorRGB2HSV_Fp(3MLIB), attributes(5)


 

Index

NAME
SYNOPSIS
DESCRIPTION
PARAMETERS
RETURN VALUES
ATTRIBUTES
SEE ALSO

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Time: 02:38:19 GMT, October 02, 2010