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+/*
+ #
+ # File : tutorial.cpp
+ # ( C++ source file )
+ #
+ # Description : View the color profile of an image, along the X-axis.
+ # This file is a part of the CImg Library project.
+ # ( http://cimg.eu )
+ #
+ # Copyright : David Tschumperle
+ # ( http://tschumperle.users.greyc.fr/ )
+ #
+ # License : CeCILL v2.0
+ # ( http://www.cecill.info/licences/Licence_CeCILL_V2-en.html )
+ #
+ # This software is governed by the CeCILL license under French law and
+ # abiding by the rules of distribution of free software. You can use,
+ # modify and/ or redistribute the software under the terms of the CeCILL
+ # license as circulated by CEA, CNRS and INRIA at the following URL
+ # "http://www.cecill.info".
+ #
+ # As a counterpart to the access to the source code and rights to copy,
+ # modify and redistribute granted by the license, users are provided only
+ # with a limited warranty and the software's author, the holder of the
+ # economic rights, and the successive licensors have only limited
+ # liability.
+ #
+ # In this respect, the user's attention is drawn to the risks associated
+ # with loading, using, modifying and/or developing or reproducing the
+ # software by the user in light of its specific status of free software,
+ # that may mean that it is complicated to manipulate, and that also
+ # therefore means that it is reserved for developers and experienced
+ # professionals having in-depth computer knowledge. Users are therefore
+ # encouraged to load and test the software's suitability as regards their
+ # requirements in conditions enabling the security of their systems and/or
+ # data to be ensured and, more generally, to use and operate it in the
+ # same conditions as regards security.
+ #
+ # The fact that you are presently reading this means that you have had
+ # knowledge of the CeCILL license and that you accept its terms.
+ #
+*/
+
+// Include CImg library file and use its main namespace
+#include "CImg.h"
+using namespace cimg_library;
+
+#ifndef cimg_imagepath
+#define cimg_imagepath "img/"
+#endif
+
+// Main procedure
+//----------------
+int main(int argc,char **argv) {
+
+ // Define program usage and read command line parameters
+ //-------------------------------------------------------
+
+ // Display program usage, when invoked from the command line with option '-h'.
+ cimg_usage("View the color profile of an image along the X axis");
+
+ // Read image filename from the command line (or set it to "img/parrot.ppm" if option '-i' is not provided).
+ const char* file_i = cimg_option("-i",cimg_imagepath "parrot.ppm","Input image");
+
+ // Read pre-blurring variance from the command line (or set it to 1.0 if option '-blur' is not provided).
+ const double sigma = cimg_option("-blur",1.0,"Variance of gaussian pre-blurring");
+
+ // Init variables
+ //----------------
+
+ // Load an image, transform it to a color image (if necessary) and blur it with the standard deviation sigma.
+ const CImg<unsigned char> image = CImg<>(file_i).normalize(0,255).blur((float)sigma).resize(-100,-100,1,3);
+
+ // Create two display window, one for the image, the other for the color profile.
+ CImgDisplay
+ main_disp(image,"Color image (Try to move mouse pointer over)",0),
+ draw_disp(500,400,"Color profile of the X-axis",0);
+
+ // Define colors used to plot the profile, and a hatch to draw the vertical line
+ unsigned int hatch = 0xF0F0F0F0;
+ const unsigned char
+ red[] = { 255,0,0 },
+ green[] = { 0,255,0 },
+ blue [] = { 0,0,255 },
+ black[] = { 0,0,0 };
+
+ // Enter event loop. This loop ends when one of the two display window is closed or
+ // when the keys 'ESC' or 'Q' are pressed.
+ while (!main_disp.is_closed() && !draw_disp.is_closed() &&
+ !main_disp.is_keyESC() && !draw_disp.is_keyESC() && !main_disp.is_keyQ() && !draw_disp.is_keyQ()) {
+
+ // Handle display window resizing (if any)
+ if (main_disp.is_resized()) main_disp.resize().display(image);
+ draw_disp.resize();
+
+ if (main_disp.mouse_x()>=0 && main_disp.mouse_y()>=0) { // Mouse pointer is over the image
+
+ const int
+ xm = main_disp.mouse_x(), // X-coordinate of the mouse pointer over the image
+ ym = main_disp.mouse_y(), // Y-coordinate of the mouse pointer over the image
+ xl = xm*draw_disp.width()/main_disp.width(), // Corresponding X-coordinate of the hatched line
+ x = xm*image.width()/main_disp.width(), // Corresponding X-coordinate of the pointed pixel in the image
+ y = ym*image.height()/main_disp.height(); // Corresponding Y-coordinate of the pointex pixel in the image
+
+ // Retrieve color component values at pixel (x,y)
+ const unsigned int
+ val_red = image(x,y,0),
+ val_green = image(x,y,1),
+ val_blue = image(x,y,2);
+
+ // Create and display the image of the intensity profile
+ CImg<unsigned char>(draw_disp.width(),draw_disp.height(),1,3,255).
+ draw_grid(-50*100.0f/image.width(),-50*100.0f/256,0,0,false,true,black,0.2f,0xCCCCCCCC,0xCCCCCCCC).
+ draw_axes(0,image.width() - 1.0f,255.0f,0.0f,black).
+ draw_graph(image.get_shared_row(y,0,0),red,1,1,0,255,1).
+ draw_graph(image.get_shared_row(y,0,1),green,1,1,0,255,1).
+ draw_graph(image.get_shared_row(y,0,2),blue,1,1,0,255,1).
+ draw_text(30,5,"Pixel (%d,%d)={%d %d %d}",black,0,1,16,
+ main_disp.mouse_x(),main_disp.mouse_y(),val_red,val_green,val_blue).
+ draw_line(xl,0,xl,draw_disp.height() - 1,black,0.5f,hatch=cimg::rol(hatch)).
+ display(draw_disp);
+ } else
+ // else display a text in the profile display window.
+ CImg<unsigned char>(draw_disp.width(),draw_disp.height()).fill(255).
+ draw_text(draw_disp.width()/2 - 130,draw_disp.height()/2 - 5,"Mouse pointer is outside the image",
+ black,0,1,16).display(draw_disp);
+
+ // Temporize event loop
+ cimg::wait(20);
+ }
+
+ return 0;
+}