message: Fix mipgen windows build.
diff: #include <fstream>
  #include <iostream>
  +#define STB_IMAGE_IMPLEMENTATION
  +#include <stb_image.h>
  +
  using namespace image;
  using namespace std;
  using namespace utils;
  @@ -163,7 +166,6 @@ static int handleArguments(int argc, char* argv[]) {
  g_createGallery = true;
  break;
  case 'k': {
  - bool isvalid;
  g_filter = filterFromString(arg.c_str());
  if (g_filter == Filter::DEFAULT) {
  cerr << "Warning: unrecognized filter, falling back to DEFAULT." << endl;
  