CPSC 120 Example of creating an image using GraphicsMagick and rasterizing some text into the image. Uses X11 color names instead of RGB color values.

cpsc120_image_with_text.cc

// Gist https://gist.github.com/mshafae/c60dcd64a98e664c6d75115e7f57fe41
// Filename cpsc120_image_with_text.cc
// CompileCommand clang++ -std=c++17 -I /usr/include/GraphicsMagick -lGraphicsMagick++ cpsc120_image_with_text
// Create a simple, small image from a given
// filename. GraphicsMagick will figure out how to output to the given file
// format.
// Supported formats: http://www.graphicsmagick.org/formats.html
// Example:
// clang++ -std=c++17 -I /usr/include/GraphicsMagick -lGraphicsMagick++ cpsc120_image_with_text
// ./a.out my_image.jpg
// ./a.out my_image.png

#include <Magick++.h>

#include <cmath>
#include <iostream>
#include <sstream>
#include <string>
#include <vector>

int main(int argc, char* argv[]) {
  // Set these to whatever dimensions you want the output image to be.
  // Warning: don't make this too big or your program will take a long time
  // to execute.
  const int kImageWidth{1024};
  const int kImageHeight{512};
  // This initializes the image library we are using.
  Magick::InitializeMagick(*argv);
  std::vector<std::string> args{argv, argv + argc};
  if (args.size() < 2) {
    std::cout << "Please provide a path to a file.\n";
    std::cout << "For example: " << args.at(0) << " my_image.jpg\n";
    return 1;
  }
  std::string output_file_name;
  output_file_name = args.at(1);

  // Let's specify a color by using the X11 color name
  // See https://en.wikipedia.org/wiki/X11_color_names
  Magick::Color orange = Magick::Color("orange");
  Magick::Image image(Magick::Geometry(kImageWidth, kImageHeight), orange);

  // Let's use the font Helvetica
  image.font("Helvetica");
  // Let's set it's size to 1/3 the number of rows the image has
  image.fontPointsize(image.rows() / 3.0);
  // Let's specify a color by using the X11 color name
  // See https://en.wikipedia.org/wiki/X11_color_names
  image.fillColor(Magick::Color("navy"));
  // A message to write in the image.
  std::string message{"Go Titans!"};
  // Center the text and draw it.
  image.annotate(message, Magick::CenterGravity);
  // Write out the image to the computer user specified file name.
  image.write(output_file_name);

  return 0;
}