00001 /** \file
00002  * \brief HSI Color Manipulation
00003  *
00004  * See Copyright Notice in im_lib.h
00005  */
00006 
00007 #ifndef __IM_COLORHSI_H
00008 #define __IM_COLORHSI_H
00009 
00010 #if defined(__cplusplus)
00011 extern "C" {
00012 #endif
00013 
00014 
00015 /** \defgroup hsi HSI Color Coordinate System Conversions
00016  *
00017  * \par
00018  * HSI is just the RGB color space written in a different coordinate system.
00019  * \par
00020  * "I" is defined along the cube diagonal. It ranges from 0 (black) to 1 (white). \n
00021  * HS are the polar coordinates of a plane normal to "I". \n
00022  * "S" is the normal distance from the diagonal of the RGB cube. It ranges from 0 to Smax. \n
00023  * "H" is the angle starting from the red vector, given in degrees.
00024  * \par
00025  * This is not a new color space, this is exactly the same gammut as RGB. \n
00026  * Since it is still a cube, Smax depends on H. 
00027  * \par
00028  * See \ref im_colorhsi.h
00029  * \ingroup color */
00030 
00031 
00032 /** Returns the maximum S for H (here in radians) and I.
00033  * \ingroup hsi */
00034 float imColorHSI_Smax(float h, double cosh, double sinh, float i);
00035 
00036 /** Returns I where S is maximum given H (here in radians).
00037  * \ingroup hsi */
00038 float imColorHSI_ImaxS(float h, double cosh, double sinh);
00039 
00040 /** Converts from RGB to HSI.
00041  * \ingroup hsi */
00042 void imColorRGB2HSI(float r, float g, float b, float *h, float *s, float *i);
00043 
00044 /** Converts from RGB (byte) to HSI.
00045  * \ingroup hsi */
00046 void imColorRGB2HSIbyte(unsigned char r, unsigned char g, unsigned char b, float *h, float *s, float *i);
00047 
00048 /** Converts from HSI to RGB.
00049  * \ingroup hsi */
00050 void imColorHSI2RGB(float h, float s, float i, float *r, float *g, float *b);
00051 
00052 /** Converts from HSI to RGB (byte).
00053  * \ingroup hsi */
00054 void imColorHSI2RGBbyte(float h, float s, float i, unsigned char *r, unsigned char *g, unsigned char *b);
00055 
00056 
00057 #if defined(__cplusplus)
00058 }
00059 #endif
00060 
00061 #endif