Functions

HSI Color Coordinate System Conversions
[Color Manipulation]

Collaboration diagram for HSI Color Coordinate System Conversions:

Functions

float imColorHSI_ImaxS (float h, double cosh, double sinh)
void imColorRGB2HSI (float r, float g, float b, float *h, float *s, float *i)
void imColorRGB2HSIbyte (unsigned char r, unsigned char g, unsigned char b, float *h, float *s, float *i)
void imColorHSI2RGB (float h, float s, float i, float *r, float *g, float *b)
void imColorHSI2RGBbyte (float h, float s, float i, unsigned char *r, unsigned char *g, unsigned char *b)

Detailed Description

HSI is just the RGB color space written in a different coordinate system.
"I" is defined along the cube diagonal. It ranges from 0 (black) to 1 (white).
HS are the polar coordinates of a plane normal to "I".
"S" is the normal distance from the diagonal of the RGB cube. It ranges from 0 to 1.
"H" is the angle starting from the red vector, given in degrees.
This is not a new color space, this is exactly the same gamut as RGB.
See im_colorhsi.h

Function Documentation

float imColorHSI_ImaxS ( float  h,
double  cosh,
double  sinh 
)

Returns I where S is maximum given H (here in radians).

void imColorRGB2HSI ( float  r,
float  g,
float  b,
float *  h,
float *  s,
float *  i 
)

Converts from RGB to HSI.

void imColorRGB2HSIbyte ( unsigned char  r,
unsigned char  g,
unsigned char  b,
float *  h,
float *  s,
float *  i 
)

Converts from RGB (byte) to HSI.

void imColorHSI2RGB ( float  h,
float  s,
float  i,
float *  r,
float *  g,
float *  b 
)

Converts from HSI to RGB.

void imColorHSI2RGBbyte ( float  h,
float  s,
float  i,
unsigned char *  r,
unsigned char *  g,
unsigned char *  b 
)

Converts from HSI to RGB (byte).