[ VIGRA Homepage | Function Index | Class Index | Namespaces | File List | Main Page ]

palette.cxx VIGRA

Create series of slices through different color spaces. Usage: example_palette luv, generates luv_*.gif (44 images)

/************************************************************************/
/* */
/* Copyright 1998-2002 by Ullrich Koethe */
/* */
/* This file is part of the VIGRA computer vision library. */
/* The VIGRA Website is */
/* http://hci.iwr.uni-heidelberg.de/vigra/ */
/* Please direct questions, bug reports, and contributions to */
/* ullrich.koethe@iwr.uni-heidelberg.de or */
/* vigra@informatik.uni-hamburg.de */
/* */
/* Permission is hereby granted, free of charge, to any person */
/* obtaining a copy of this software and associated documentation */
/* files (the "Software"), to deal in the Software without */
/* restriction, including without limitation the rights to use, */
/* copy, modify, merge, publish, distribute, sublicense, and/or */
/* sell copies of the Software, and to permit persons to whom the */
/* Software is furnished to do so, subject to the following */
/* conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the */
/* Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES */
/* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND */
/* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT */
/* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, */
/* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING */
/* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR */
/* OTHER DEALINGS IN THE SOFTWARE. */
/* */
/************************************************************************/
#include <stdio.h>
#include <iostream>
#include <algorithm>
#include <vigra/multi_array.hxx>
#include <vigra/stdimagefunctions.hxx>
#include <vigra/impex.hxx>
#include <vigra/colorconversions.hxx>
using namespace vigra;
template<class Polar2Cartesian, class Cartesian2RGB, class RGB2RGBPrime>
void createColorVsSaturation(MultiArray<2, RGBValue<UInt8> > & result, double brightness,
Polar2Cartesian polar2Cartesian, Cartesian2RGB cartesian2RGB, RGB2RGBPrime rgb2RGBPrime)
{
int w = result.width();
int h = result.height();
for(int y=0; y<h; ++y)
{
for(int x=0; x<w; ++x)
{
double saturation = (float)x / (w-1);
double color = (float)y / (h-1) * 360.0;
RGBValue<float> rgb = cartesian2RGB(
polar2Cartesian(color, brightness, saturation));
if(saturation > 1.0 ||
rgb.red() < 0.0 || rgb.red() > 255.0 ||
rgb.green() < 0.0 || rgb.green() > 255.0 ||
rgb.blue() < 0.0 || rgb.blue() > 255.0)
{
result(x,y) = RGBValue<unsigned char>(170.0);
}
else
{
result(x,y) = rgb2RGBPrime(rgb);
}
}
}
}
template<class Polar2Cartesian, class Cartesian2RGB, class RGB2RGBPrime>
void createColorVsBrightness(MultiArray<2, RGBValue<UInt8> > & result, double saturation,
Polar2Cartesian polar2Cartesian, Cartesian2RGB cartesian2RGB, RGB2RGBPrime rgb2RGBPrime)
{
int w = result.width();
int h = result.height();
for(int y=0; y<h; ++y)
{
for(int x=0; x<w; ++x)
{
double brightness = (float)x / (w-1);
double color = (float)y / (h-1) * 360.0;
RGBValue<float> rgb = cartesian2RGB(
polar2Cartesian(color, brightness, saturation));
if(saturation > 1.0 ||
rgb.red() < 0.0 || rgb.red() > 255.0 ||
rgb.green() < 0.0 || rgb.green() > 255.0 ||
rgb.blue() < 0.0 || rgb.blue() > 255.0)
{
result(x,y) = RGBValue<unsigned char>(170.0);
}
else
{
result(x,y) = rgb2RGBPrime(rgb);
}
}
}
}
template<class Polar2Cartesian, class Cartesian2RGB, class RGB2RGBPrime>
void createSaturationVsBrightness(MultiArray<2, RGBValue<UInt8> > & result, double color,
Polar2Cartesian polar2Cartesian, Cartesian2RGB cartesian2RGB, RGB2RGBPrime rgb2RGBPrime)
{
int w = result.width();
int h = result.height();
for(int y=0; y<h; ++y)
{
for(int x=0; x<w; ++x)
{
double brightness = (float)x / (w-1);
double saturation = (float)y / (h-1);
RGBValue<float> rgb = cartesian2RGB(
polar2Cartesian(color, brightness, saturation));
if(saturation > 1.0 ||
rgb.red() < 0.0 || rgb.red() > 255.0 ||
rgb.green() < 0.0 || rgb.green() > 255.0 ||
rgb.blue() < 0.0 || rgb.blue() > 255.0)
{
result(x,y) = RGBValue<unsigned char>(170.0);
}
else
{
result(x,y) = rgb2RGBPrime(rgb);
}
}
}
}
template<class Polar2Cartesian, class Cartesian2RGB, class RGB2RGBPrime>
void createColorCircle(MultiArray<2, RGBValue<UInt8> > & result, double brightness,
Polar2Cartesian polar2Cartesian, Cartesian2RGB cartesian2RGB, RGB2RGBPrime rgb2RGBPrime)
{
int w = result.width();
int h = result.height();
for(int y=0; y<h; ++y)
{
for(int x=0; x<w; ++x)
{
double dx = x/128.0 - 1.0;
double dy = -y/128.0 + 1.0;
double color = 180.0/M_PI*std::atan2(dy,dx);
double saturation = std::sqrt(dx*dx+dy*dy);
RGBValue<float> rgb = cartesian2RGB(
polar2Cartesian(color, brightness, saturation));
if(saturation > 1.0 ||
rgb.red() < 0.0 || rgb.red() > 255.0 ||
rgb.green() < 0.0 || rgb.green() > 255.0 ||
rgb.blue() < 0.0 || rgb.blue() > 255.0)
{
result(x,y) = RGBValue<unsigned char>(170.0);
}
else
{
result(x,y) = rgb2RGBPrime(rgb);
}
}
}
}
void write(char const * colorspace, char const * diagram, int i, MultiArray<2, RGBValue<UInt8> > const & img)
{
char buf[1000];
if(i < 10)
sprintf(buf, "%s_%s_0%d.gif", colorspace, diagram, i);
else
sprintf(buf, "%s_%s_%d.gif", colorspace, diagram, i);
std::cout << "Wrote " << buf << std::endl;
}
template<class Polar2Cartesian, class Cartesian2RGB, class RGB2RGBPrime>
void createColorSpaceSlices(char const * colorspace,
Polar2Cartesian polar2Cartesian, Cartesian2RGB cartesian2RGB, RGB2RGBPrime rgb2RGBPrime)
{
int w = 257;
int h = 257;
int Ymax = 10;
for(int i=0; i<=Ymax; ++i)
{
createColorVsSaturation(result, (float)i/Ymax,
polar2Cartesian, cartesian2RGB, rgb2RGBPrime);
write(colorspace, "ColorVsSaturation", i, result);
createColorVsBrightness(result, (float)i/Ymax,
polar2Cartesian, cartesian2RGB, rgb2RGBPrime);
write(colorspace, "ColorVsBrightness", i, result);
createSaturationVsBrightness(result, (float)i/Ymax*360.0,
polar2Cartesian, cartesian2RGB, rgb2RGBPrime);
write(colorspace, "SaturationVsBrightness", i, result);
createColorCircle(result, (float)i/Ymax,
polar2Cartesian, cartesian2RGB, rgb2RGBPrime);
write(colorspace, "ColorCircle", i, result);
}
}
void usage(char const * prog)
{
std::cerr << "Usage: " << prog << " colorspace\n"
"with colorspace in [lab luv ypbpr ycbcr yiq yuv]\n\n";
std::cerr << "This programm calculates slices through the given color space\n"
"Images are named 'lab_SaturationVsBrightness_01.gif' etc.\n"
"where the first part of the name designates the colorspace used,\n"
"the second part says what is varied on the image\n"
"and the number codes the value of the quantity that is kept\n"
"constant in the image - 01 in the example means that the color\n"
"angle is 36 degrees = 1 * 360 degrees / 10\n";
}
int main(int argc, char ** argv)
{
if(argc <2)
{
usage(argv[0]);
return 1;
}
try
{
typedef TinyVector<float, 3> (*PolarFct)(double, double, double);
std::string colorspace(argv[1]);
if(colorspace == "lab")
{
createColorSpaceSlices("lab",
}
else if(colorspace == "luv")
{
createColorSpaceSlices("luv",
}
else if(colorspace == "ypbpr")
{
createColorSpaceSlices("ypbpr",
&NumericTraits<RGBValue<unsigned char> >::fromRealPromote);
}
else if(colorspace == "ycbcr")
{
createColorSpaceSlices("ycbcr",
&NumericTraits<RGBValue<unsigned char> >::fromRealPromote);
}
else if(colorspace == "yiq")
{
createColorSpaceSlices("yiq",
&NumericTraits<RGBValue<unsigned char> >::fromRealPromote);
}
else if(colorspace == "yuv")
{
createColorSpaceSlices("yuv",
&NumericTraits<RGBValue<unsigned char> >::fromRealPromote);
}
else
{
std::cerr << "Unknown colorspace: " << colorspace << std::endl;
usage(argv[0]);
return 1;
}
}
catch (std::exception & e)
{
std::cout << e.what() << std::endl;
return 1;
}
return 0;
}

© Ullrich Köthe (ullrich.koethe@iwr.uni-heidelberg.de)
Heidelberg Collaboratory for Image Processing, University of Heidelberg, Germany

html generated using doxygen and Python
vigra 1.11.1 (Fri May 19 2017)