text: /**
   * @file sketchify.h
   * Declaration of the sketchify function.
   */
  
  #pragma once
  
  #include <string>
  
  /**
   * Reads in an image, runs a simple "sketchify" algorithm on it to highlight
   * edges in the image, and then writes the resulting image back out to a
   * specified file.
  
   * @param inputFile the name of the PNG file to sketchify
   * @param outputFile the name of the file where the output will be written
   */
  void sketchify(std::string inputFile, std::string outputFile);
  