hyperion.ng/libsrc/utils/HsvTransform.cpp

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#include <iostream>
#include <utils/HsvTransform.h>
HsvTransform::HsvTransform()
: _saturationGain(1.0)
, _valueGain(1.0)
{
}
HsvTransform::HsvTransform(double saturationGain, double valueGain) :
_saturationGain(saturationGain),
_valueGain(valueGain)
{
}
HsvTransform::~HsvTransform()
{
}
void HsvTransform::setSaturationGain(double saturationGain)
{
_saturationGain = saturationGain;
}
double HsvTransform::getSaturationGain() const
{
return _saturationGain;
}
void HsvTransform::setValueGain(double valueGain)
{
_valueGain = valueGain;
}
double HsvTransform::getValueGain() const
{
return _valueGain;
}
void HsvTransform::transform(uint8_t & red, uint8_t & green, uint8_t & blue) const
{
if (_saturationGain != 1.0 || _valueGain != 1.0)
{
uint16_t hue;
uint8_t saturation, value;
rgb2hsv(red, green, blue, hue, saturation, value);
int s = saturation * _saturationGain;
if (s > 255)
saturation = 255;
else
saturation = s;
int v = value * _valueGain;
if (v > 255)
value = 255;
else
value = v;
hsv2rgb(hue, saturation, value, red, green, blue);
}
}
void HsvTransform::rgb2hsv(uint8_t red, uint8_t green, uint8_t blue, uint16_t & hue, uint8_t & saturation, uint8_t & value)
{
uint8_t rgbMin, rgbMax;
rgbMin = red < green ? (red < blue ? red : blue) : (green < blue ? green : blue);
rgbMax = red > green ? (red > blue ? red : blue) : (green > blue ? green : blue);
value = rgbMax;
if (value == 0)
{
hue = 0;
saturation = 0;
return;
}
saturation = 255 * long(rgbMax - rgbMin) / value;
if (saturation == 0)
{
hue = 0;
return;
}
if (rgbMax == red)
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{
// start from 360 to be sure that we won't assign a negative number to the unsigned hue value
hue = 360 + 60 * (green - blue) / (rgbMax - rgbMin);
if (hue > 359)
hue -= 360;
}
else if (rgbMax == green)
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{
hue = 120 + 60 * (blue - red) / (rgbMax - rgbMin);
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}
else
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{
hue = 240 + 60 * (red - green) / (rgbMax - rgbMin);
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}
}
void HsvTransform::hsv2rgb(uint16_t hue, uint8_t saturation, uint8_t value, uint8_t & red, uint8_t & green, uint8_t & blue)
{
uint8_t region, remainder, p, q, t;
if (saturation == 0)
{
red = value;
green = value;
blue = value;
return;
}
region = hue / 60;
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remainder = (hue - (region * 60)) * 256 / 60;
p = (value * (255 - saturation)) >> 8;
q = (value * (255 - ((saturation * remainder) >> 8))) >> 8;
t = (value * (255 - ((saturation * (255 - remainder)) >> 8))) >> 8;
switch (region)
{
case 0:
red = value; green = t; blue = p;
break;
case 1:
red = q; green = value; blue = p;
break;
case 2:
red = p; green = value; blue = t;
break;
case 3:
red = p; green = q; blue = value;
break;
case 4:
red = t; green = p; blue = value;
break;
default:
red = value; green = p; blue = q;
break;
}
}