text: #include <stdio.h>
  #include <SDL/SDL.h>
  #include <SDL/SDL_image.h>
  #include <assert.h>
  #include <emscripten.h>
  #include <unistd.h>
  
  int testImage(SDL_Surface* screen, const char* fileName) {
    SDL_Surface *image = IMG_Load(fileName);
    if (!image)
    {
       printf("IMG_Load: %s\n", IMG_GetError());
       return 0;
    }
    assert(image->format->BitsPerPixel == 32);
    assert(image->format->BytesPerPixel == 4);
    assert(image->pitch == 4*image->w);
    int result = image->w;
  
    SDL_BlitSurface (image, NULL, screen, NULL);
    SDL_FreeSurface (image);
  
    return result;
  }
  
  int main() {
    SDL_Init(SDL_INIT_VIDEO);
    SDL_Surface *screen = SDL_SetVideoMode(600, 450, 32, SDL_SWSURFACE);
  
    int result = 0;
  
    result |= testImage(screen, "screenshot.jpg"); // absolute path
    assert(result != 0);
  
    SDL_Flip(screen);
  
    printf("you should see an image.\n");
  
    SDL_Quit();
  
    return 0;
  }
  
  