00001 /** \file
00002  * \brief HSI Color Manipulation
00003  *
00004  * See Copyright Notice in im_lib.h
00005  * $Id: im_colorhsi.h,v 1.1 2005/04/02 22:07:00 scuri Exp $
00006  */
00007 
00008 #ifndef __IM_COLORHSI_H
00009 #define __IM_COLORHSI_H
00010 
00011 #if defined(__cplusplus)
00012 extern "C" {
00013 #endif
00014 
00015 
00016 /** \defgroup hsi HSI Color Coordinate System Conversions
00017  *
00018  * \par
00019  * HSI is just the RGB color space written in a different coordinate system.
00020  * \par
00021  * "I" is defined along the cube diagonal. It ranges from 0 (black) to 1 (white). \n
00022  * HS are the polar coordinates of a plane normal to "I". \n
00023  * "S" is the normal distance from the diagonal of the RGB cube. It ranges from 0 to Smax. \n
00024  * "H" is the angle starting from the red vector, given in degrees.
00025  * \par
00026  * This is not a new color space, this is exactly the same gammut as RGB. \n
00027  * Since it is still a cube, Smax depends on H. 
00028  * \par
00029  * See \ref im_colorhsi.h
00030  * \ingroup color */
00031 
00032 
00033 /** Returns the maximum S for H (here in radians) and I.
00034  * \ingroup hsi */
00035 float imColorHSI_Smax(float h, double cosh, double sinh, float i);
00036 
00037 /** Returns I where S is maximum given H (here in radians).
00038  * \ingroup hsi */
00039 float imColorHSI_ImaxS(float h, double cosh, double sinh);
00040 
00041 /** Converts from RGB to HSI.
00042  * \ingroup hsi */
00043 void imColorRGB2HSI(float r, float g, float b, float *h, float *s, float *i);
00044 
00045 /** Converts from RGB (byte) to HSI.
00046  * \ingroup hsi */
00047 void imColorRGB2HSIbyte(unsigned char r, unsigned char g, unsigned char b, float *h, float *s, float *i);
00048 
00049 /** Converts from HSI to RGB.
00050  * \ingroup hsi */
00051 void imColorHSI2RGB(float h, float s, float i, float *r, float *g, float *b);
00052 
00053 /** Converts from HSI to RGB (byte).
00054  * \ingroup hsi */
00055 void imColorHSI2RGBbyte(float h, float s, float i, unsigned char *r, unsigned char *g, unsigned char *b);
00056 
00057 
00058 #if defined(__cplusplus)
00059 }
00060 #endif
00061 
00062 #endif